166 results on '"Koji Fukuzawa"'
Search Results
2. Predictors of recurrence in patients without non‐inducibility of ventricular tachycardia at the end of ablation
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Kazutaka Nakasone, Koji Fukuzawa, Kunihiko Kiuchi, Mitsuru Takami, Jun Sakai, Toshihiro Nakamura, Atsusuke Yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kyoko Yamamoto, Yuya Suzuki, Ken‐ichi Tani, Hidehiro Iwai, Yusuke Nakanishi, and Ken‐ichi Hirata
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catheter ablation ,ventricular tachycardia ,ventricular tachycardia non‐inducibility ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Ventricular tachycardia (VT) non‐inducibility at the end of ablation is associated with a less likely VT recurrence. However, it is not clear whether we should use VT non‐inducibility as a routine end point of VT ablation. The aim of this study was to evaluate VT recurrence in patients in whom VT non‐inducibility was not achieved at the end of the radiofrequency (RF) ablation and the factors attributing to the VT recurrence. Methods We analyzed that 62 patients in whom VT non‐inducibility was not achieved at the end of the RF ablation were studied. Results Over 2 years, 22 (35%) of the cases had VT recurrences. A multivariate analysis showed that an LVEF ≥35% (HR: 0.19; 95% CI: 0.06–0.49; p
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- 2023
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3. Trans-jugular vein approach for ablation of ventricular premature contractions originating from the tricuspid annulus
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Koji Fukuzawa, Hiroyuki Takahara, Yuya Suzuki, and Ken-ichi Hirata
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Ventricular premature contraction ,Ablation ,Trans-jugular approach ,Tricuspid annulus ,Intracardiac ultrasound ,Mapping ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
A young-male underwent radiofrequency (RF) ablation of ventricular premature contractions (VPCs) of over 30,000/day and the morphology exhibited left bundle branch block and a superior axis, which indicated the VPCs originated from the inferior portion of the right ventricle (RV). While the PENTARAY catheter was placed under the tricuspid valve (TV), the earliest potential, which preceded the QRS onset by 34 ms, was recorded. Pace mapping there presented a very similar QRS morphology to the target VPC. However, the radiofrequency (RF)-catheter could not be placed under the TV even when a deflectable sheath was used, because the deflectable curve of the RF-catheter was larger than that of the PENTARAY. An over-the-vale RF application was not effective, so the trans-jugular approach with a deflectable sheath was indicated. The tip of the sheath was placed at a higher portion of the RV cavity to maintain an adequate distance for the RF-catheter tip to be deflected and placed under the TV. With this maneuver, the tip of the RF-catheter was successfully placed under the TV, which was confirmed by intracardiac ultrasound. Small atrial potentials and larger ventricular potentials could be recorded from the distal tip of the RF-catheter, which might indicate that the tip was placed at the TV annulus. An RF application at that site permanently abolished the VPC. Placing the tip of the RF-catheter under the TV by the femoral approach is very difficult in some cases. The trans-jugular approach with a deflectable sheath is one option for arrhythmias from the TV.
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- 2023
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4. Ventricular arrhythmia events in heart failure patients with cardiac resynchronization therapy with or without a defibrillator for primary prevention
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Toshihiro Nakamura, Koji Fukuzawa, Kunihiko Kiuchi, Mitsuru Takami, Yusuke Sonoda, Hiroyuki Takahara, Kazutaka Nakasone, Kyoko Yamamoto, Yuya Suzuki, Ken‐ichi Tani, Hidehiro Iwai, Yusuke Nakanishi, Mitsuhiko Shoda, Atsushi Murakami, Shogo Yonehara, and Ken‐ichi Hirata
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cardiac resynchronization therapy ,heart failure with reduced ejection fraction ,primary prevention ,ventricular arrhythmia ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background It is uncertain whether cardiac resynchronization therapy with a defibrillator (CRT‐D) provides better survival benefits than a CRT‐pacemaker (CRT‐P) in heart failure patients with a reduced ejection fraction (≦35%, HFrEF) treated with contemporary HF therapy. Methods We retrospectively analyzed the ventricular arrhythmia (VAs; sustained ventricular tachycardia/fibrillation) events in HFrEF patients who underwent CRT without a prior history of VAs or aborted sudden cardiac death before the CRT implantation. Between January/2010 and December/2020, a CRT device was implanted in 79 HFrEF patients (mean age: 69 ± 12 years, male: 57, ischemic cardiomyopathy: 16). CRT‐D and CRT‐P devices were implanted in 50 and 29 patients, respectively, at each physician's discretion. CRT‐Ds were indicated in younger patients than were CRT‐Ps (66 ± 12 vs. 73 ± 12 years, p = 0.03), but the gender distribution did not differ (female, 24% [12 of 50] vs. 35% [10 of 29], p = 0.44). The VA events during a median follow‐up of 3.5‐years (interquartile range [IQR]:1.6–5.5) and their predictors were analyzed. Results VA events occurred in 9 patients with CRT‐Ds (18%) and one with a CRT‐P (3%, p = 0.08). The VA event rate was significantly lower in patients without a prior non‐sustained ventricular tachycardia (NSVT: ≥3 beats; rate, ≥120 bpm; lasting
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- 2022
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5. Impact of corticosteroid use on the clinical response and prognosis in patients with cardiac sarcoidosis who underwent an upgrade to cardiac resynchronization therapy
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Yuya Suzuki, Mitsuru Takami, Koji Fukuzawa, Kunihiko Kiuchi, Akira Shimane, Jun Sakai, Toshihiro Nakamura, Atsusuke Yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kazutaka Nakasone, Kyoko Yamamoto, Ken‐ichi Tani, Hidehiro Iwai, Yusuke Nakanishi, and Ken‐ichi Hirata
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cardiac resynchronization therapy ,cardiac sarcoidosis ,corticosteroid ,upgrade and heart failure ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Corticosteroids are widely used in patients with cardiac sarcoidosis (CS). In addition, upgrading to cardiac resynchronization therapy (CRT) is sometimes needed. This study aimed to investigate the impact of corticosteroid use on the clinical outcomes following CRT upgrades. Methods A total of 48 consecutive patients with non‐ischemic cardiomyopathies who underwent CRT upgrades were retrospectively reviewed and divided into three groups: group 1 included CS patients taking corticosteroids before the CRT upgrade (n = 7), group 2, CS patients not taking corticosteroids before the CRT upgrade (n = 10), and group 3, non‐CS patients (n = 31). The echocardiographic response, heart failure hospitalizations, and cardiovascular deaths were evaluated. Results The baseline characteristics during CRT upgrades exhibited no significant differences in the echocardiographic data between the three groups. After the CRT upgrade, responses regarding the ejection fraction (EF) and end‐systolic volume (ESV) were significantly lower in CS patients than non‐CS patients (ΔEF: group 1, 6.7% vs. group 2, 7.7% vs. group 3, 13.6%; p = .039, ΔESV: 3.0 ml vs. ‐12.7 ml vs. ‐37.2 ml; p = .008). The rate of an echocardiographic response was lowest in group 1 (29%). There were, however, no significant differences in the cumulative freedom from a composite outcome among the three groups (p = .19). No cardiovascular deaths occurred in group 1. Conclusion The echocardiographic response to an upgrade to CRT and the long‐term prognosis in patients with CS should be carefully evaluated because of the complex etiologies and impact of immunosuppressive therapy.
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- 2022
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6. Variations in the bifurcation of deep femoral artery important for electrophysiologist
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Kazutaka Nakasone, Kunihiko Kiuchi, Hiromi Hashimura, Mitsuru Takami, Koji Fukuzawa, and Ken‐ichi Hirata
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anatomic variation ,complication ,cryoballoon ablation ,high bifurcation of deep femoral artery ,Medicine ,Medicine (General) ,R5-920 - Abstract
Abstract Knowing the vascular anatomy of the common femoral artery bifurcation and ultrasound‐guided puncture, including doppler, is helpful in recognizing anatomic variations and avoiding complications.
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- 2023
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7. The impact of the atrial wall thickness in normal/mild late‐gadolinium enhancement areas on atrial fibrillation rotors in persistent atrial fibrillation patients
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Toshihiro Nakamura, Kunihiko Kiuchi, Koji Fukuzawa, Mitsuru Takami, Yoshiaki Watanabe, Yu Izawa, Makoto Takemoto, Jun Sakai, Atsusuke Yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kazutaka Nakasone, Kyoko Yamamoto, Yuya Suzuki, Ken‐ichi Tani, Noriyuki Negi, Atsushi Kono, Takashi Ashihara, and Ken‐ichi Hirata
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atrial fibrillation ,atrial wall thickness ,fibrosis ,late‐gadolinium enhancement magnetic resonance imaging ,rotor ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Some of atrial fibrillation (AF) drivers are found in normal/mild late‐gadolinium enhancement (LGE) areas, as well as moderate ones. The atrial wall thickness (AWT) has been reported to be important as a possible AF substrate. However, the AWT and degree of LGEs as an AF substrate has not been fully validated in humans. Objective The purpose of this study was to evaluate the impact of the AWT in normal/mild LGE areas on AF drivers. Methods A total of 287 segments in 15 persistent AF patients were assessed. AF drivers were defined as non‐passively activated areas (NPAs), where rotational activation was frequently observed, and were detected by the novel real‐time phase mapping (ExTRa Mapping), mild LGE areas were defined as areas with a volume ratio of the enhancement voxel of 0% to
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- 2022
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8. Ventricular tachycardia based on cardiac sarcoidosis with a narrow QRS complex, ablated on the left ventricle free-wall
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Hiroshi Imada, Koji Fukuzawa, Yu Izawa, Kunihiko Kiuchi, and Ken-ichi Hirata
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Ventricular tachycardia ,Catheter ablation ,Cardiac sarcoidosis ,Narrow QRS complex ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
A septuagenarian female with cardiac sarcoidosis suffered from drug refractory ventricular tachycardia (VT) requiring multiple implantable cardioverter-defibrillator shocks. The QRS complex during the VT was very similar to that during sinus rhythm although the QRS width during the VT (142 ms) was relatively wider than that during sinus rhythm (107 ms). The VT exit was located on the ventricular septum close to the His-bundle recording region. However, the critical pathway of this VT was detected on the anterior free wall of the left ventricle (LV), and a radiofrequency application at that site could terminate the VT. No Purkinje potentials were recorded there during the VT or sinus rhythm. According to the electrophysiological study, 3-D mapping, and the response to the ablation, the critical circuit of the VT was surrounded by a protected area of scar associated with cardiac sarcoidosis. As a result, the VT circuit was connected to the basal septal area close to the His-Purkinje system as an outer loop of the VT circuit. This unique trajectory of the VT might have caused a similar QRS morphology to that of sinus rhythm, and the relatively narrow QRS complex despite the critical isthmus was located on the anterior free wall of the LV.
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- 2021
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9. Accessory pathway analysis using a multimodal deep learning model
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Makoto Nishimori, Kunihiko Kiuchi, Kunihiro Nishimura, Kengo Kusano, Akihiro Yoshida, Kazumasa Adachi, Yasutaka Hirayama, Yuichiro Miyazaki, Ryudo Fujiwara, Philipp Sommer, Mustapha El Hamriti, Hiroshi Imada, Makoto Takemoto, Mitsuru Takami, Masakazu Shinohara, Ryuji Toh, Koji Fukuzawa, and Ken-ichi Hirata
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Medicine ,Science - Abstract
Abstract Cardiac accessory pathways (APs) in Wolff–Parkinson–White (WPW) syndrome are conventionally diagnosed with decision tree algorithms; however, there are problems with clinical usage. We assessed the efficacy of the artificial intelligence model using electrocardiography (ECG) and chest X-rays to identify the location of APs. We retrospectively used ECG and chest X-rays to analyse 206 patients with WPW syndrome. Each AP location was defined by an electrophysiological study and divided into four classifications. We developed a deep learning model to classify AP locations and compared the accuracy with that of conventional algorithms. Moreover, 1519 chest X-ray samples from other datasets were used for prior learning, and the combined chest X-ray image and ECG data were put into the previous model to evaluate whether the accuracy improved. The convolutional neural network (CNN) model using ECG data was significantly more accurate than the conventional tree algorithm. In the multimodal model, which implemented input from the combined ECG and chest X-ray data, the accuracy was significantly improved. Deep learning with a combination of ECG and chest X-ray data could effectively identify the AP location, which may be a novel deep learning model for a multimodal model.
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- 2021
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10. Visualization of intensive atrial inflammation and fibrosis after cryoballoon ablation: PET/MRI and LGE‐MRI analysis
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Kunihiko Kiuchi, Koji Fukuzawa, Munenobu Nogami, Yoshiaki Watanabe, Mitsuru Takami, Yu Izawa, Noriyuki Negi, Katsusuke Kyotani, Shumpei Mori, and Ken‐Ichi Hirata
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atrial fibrillation ,cryoballoon ,fibrosis ,inflammation ,PET/MRI ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Atrial inflammation plays an important role in initiating atrial fibrosis, which could perpetuate atrial fibrillation (AF). However, the method of visualization of atrial inflammation has not been established. We sought to investigate whether the intensive atrial inflammation caused by cryoballoon ablation (CBA) could be detected by positron emission tomography/ magnetic resonance imaging (PET/MRI) and whether the atrial inflammation could be associated with consequent fibrosis. Methods A total of 10 paroxysmal atrial fibrillation patients after CBA were enrolled. To detect and quantify intensive atrial inflammation, PET/MRI was performed to assess regional 18F‐fluorodeoxyglucose (18F‐FDG) uptake one day after the CBA, and the standardized uptake values (SUV) max were compared between the pulmonary vein (PV) antrum where CBA could be applied and the healthy left atrial (LA) wall where CBA could not be applied. Furthermore, the atrial inflammation one day after the procedure and atrial fibrosis areas one month after the procedure were three‐dimensionally quantified by PET/MRI and late‐gadolinium enhancement magnetic resonance imaging (LGE‐MRI), respectively. Results The mean SUV max at the PV antrum was significantly higher than that on the healthy LA wall (2.12 ± 0.35 vs 1.73 ± 0.30, P = .00021). The volume of the atrial inflammation strongly correlated with that of the atrial fibrosis (r = .94 [.76‐.99], P = .00006). Conclusions The atrial inflammation after CBA could be detected by PET/MRI. CBA‐induced atrial inflammation was strongly associated with consequent lesion maturation.
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- 2021
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11. A multicenter study comparing the outcome of catheter ablation of atrial fibrillation between cryoballoon and radiofrequency ablation in patients with heart failure (CRABL‐HF): Study design
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Koji Miyamoto, Kanae Hasegawa, Hiroki Takahashi, Yoh Masue, Naoya Kataoka, Koji Fukuzawa, Keiichi Ashikaga, Takashi Noda, Kazuhiro Satomi, Hiroshi Tada, Masahiko Takagi, Satoshi Yasuda, and Kengo Kusano
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AF ,cryoballoon ,RF ablation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Catheter ablation of atrial fibrillation (AF) is increasingly performed worldwide in patients with heart failure (HF). However, it has been recently emphasized that AF ablation in patients with HF is associated with increased risks of procedure‐related complications and mortality. There are little data about the differences in the efficacy and safety between cryoballoon (CB) and radiofrequency (RF) ablation of AF in patients with HF. Methods The CRABL‐HF study is designed as a prospective, multicenter, open‐label, controlled, and randomized clinical trial comparing the efficacy and safety of AF ablation between CB and RF ablation in patients with HF (LVEF ≤40%) (UMIN Clinical Trials Registry UMIN000032433). The CRABL‐HF study will consist of 110 patients at multicenter in Japan. The patients will be registered and randomly assigned to either the CB ablation or RF ablation group with a 1:1 allocation. The primary endpoint of this study is the occurrence of atrial tachyarrhythmias (ATs) at 1 year with a blanking period of 90 days after ablation. Key secondary endpoints are the success rate of the pulmonary vein isolation, total procedural time, left atrial dwelling time, total fluoroscopy time, radiation exposure, complication rate, composite of all‐cause mortality or HF hospitalizations, cardiovascular events, change in left ventricular ejection fraction, and change in quality of life. Results The results of this study are currently under investigation. Conclusion The CRABL‐HF study is being conducted to compare the efficacy and safety of catheter ablation of AF between CB and RF ablation in patients with HF.
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- 2020
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12. Successful catheter ablation approach above the aortic sinus cusp eliminating a ventricular arrhythmia arising from the myocardial crescent beneath the interleaflet triangle: Late gadolinium enhancement magnetic resonance imaging assessment
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Kunihiko Kiuchi, Yu Izawa, Hiroyuki Toh, Mitsuru Takami, Koji Fukuzawa, and Ken‐ichi Hirata
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interleaflet triangle ,myocardial crescent ,radiofrequency catheter ablation ,ventricular arrhythmia ,Medicine ,Medicine (General) ,R5-920 - Abstract
Abstract A 61‐year‐old female with 50 000 ventricular premature contractions and a reduced left ventricular ejection fraction of 35% was referred to our center. Although the origin was considered to originate from the junction between the left and right coronary cusp, a single radiofrequency application above the aortic sinus cusp could eliminate it. LGE‐MRI was able to reveal the exact location of the single RF lesion.
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- 2021
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13. Successful catheter ablation of postoperative atrial tachycardia with conduction disturbances: Assessment by late‐gadolinium enhancement magnetic resonance imaging and high‐resolution electro‐anatomical mapping
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Kazutaka Nakasone, Kunihiko Kiuchi, Mitsuru Takami, Yu Izawa, Koji Fukuzawa, and Ken‐ichi Hirata
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catheter ablation ,late‐gadolinium enhancement magnetic resonance imaging ,postoperative atrial tachycardia ,Medicine ,Medicine (General) ,R5-920 - Abstract
Abstract Atrial tachycardia (AT) in the right atrium often occurs following open‐heart surgery. Catheter ablation for these AT is challenging and can lead to unintended conduction block. We performed late‐gadolinium enhancement magnetic resonance imaging (LGE‐MRI) prior to catheter ablation and predicted wavefront propagation during SR as well as the slow conduction zone during tachycardia. LGE‐MRI may assist predicting the conduction disturbance and reducing the risk of unexpected sinus exit block.
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- 2021
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14. One‐year clinical outcomes of anticoagulation therapy among Japanese patients with atrial fibrillation: The Hyogo AF Network (HAF‐NET) Registry
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Kiyohiro Hyogo, Akihiro Yoshida, Motoshi Takeuchi, Kunihiko Kiuchi, Koji Fukuzawa, Mitsuru Takami, Atsushi Kobori, Katsunori Okajima, Michio Odake, Toshio Okada, Akira Shimane, Yasuhiro Kawahara, Junichi Sekiya, Hiroshi Sano, Yasunori Ichikawa, Ken‐ichi Hirata, and the HAF‐NET Registry Investigators
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atrial fibrillation ,catheter ablation ,dementia ,direct oral anticoagulants ,warfarin ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Although anticoagulation therapy could reduce the risk of strokes in patients with atrial fibrillation (AF), large‐scale investigations in the direct oral anticoagulant (DOAC) and AF catheter ablation (CA) era are lacking. Methods This study was designed as a prospective, multicenter, observational study and a total of 2113 patients from 22 institutions were enrolled in the Hyogo area. Results The mean age and CHADS2 score were 70.1 ± 10.8 years old and 1.5 ± 1.1, respectively. The follow‐up period was 355 ± 43 days. CA was performed in 614 (29%) and DOACs were prescribed in 1118 (53%) patients. Ischemic strokes/systemic embolisms (SEs) and major bleeding occurred in 13 (0.6%) and 17 (0.8%) patients, respectively. New onset dementia, hospitalizations for cardiac events, and all‐cause death occurred in eight (0.4%), 60 (2.8%), and 29 (1.4%) patients, respectively. A multivariate analysis demonstrated that persistent AF and the body weight (BW) were associated with ischemic strokes/SEs and major bleeding, respectively (persistent AF: hazard ratio, 9.57; 95%CI, 1.2‐74.0; P = .03; BW: hazard ratio, 0.94; 95%CI, 0.90‐0.99; P = .02). AFCA history was associated with the cardiac events (hazard ratio, 0.44; 95%CI, 0.20‐0.99; P = .04). Age was associated with new onset dementia (hazard ratio, 1.1; 95%CI, 1.0‐1.2; P = .03). Conclusions In the DOAC and CA era, the incidence of ischemic strokes/SEs, major bleeding and cardiac events could be dramatically reduced in patients with AF. However, some unsolved issues of AF management still remain especially in elderly patients with persistent AF and a low BW.
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- 2019
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15. Successful modulation of atrial fibrillation drivers anchoring to fibrotic tissue after box isolation using an online real‐time phase mapping system: ExTRa Mapping
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Toshihiro Nakamura, Kunihiko Kiuchi, Koji Fukuzawa, Mitsuru Takami, Tomomi Akita, Hideya Suehiro, Makoto Takemoto, Jun Sakai, Atsusuke Yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kazutaka Nakasone, Kyoko Yamamoto, Ken‐ichi Hirata, and Takashi Ashihara
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atrial fibrillation ,atrial fibrillation drivers ,late gadolinium enhancement magnetic resonance imaging ,phase mapping ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract A 41‐year‐old man with persistent atrial fibrillation (AF) underwent radiofrequency (RF) catheter ablation using an online real‐time phase mapping system: ExTRa Mapping. Box isolation could not terminate AF. Subsequently, RF applications on nonpassively activated areas (NPAs), where rotational activations were frequently observed, at the posterior bottom of left atrium outside of box lesion could convert AF to common atrial flutter. Of interest, the NPA near the posterior bottom were located on the patchy fibrotic tissue area assessed by the late‐gadolinium enhancement magnetic resonance imaging. This indicated the possibility of the critical AF rotor meandering through the fibrotic tissue area.
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- 2019
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16. Electrophysiological and Pathological Impact of Medium‐Dose External Carbon Ion and Proton Beam Radiation on the Left Ventricle in an Animal Model
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Mitsuru Takami, Tetsuya Hara, Tomoaki Okimoto, Masaki Suga, Koji Fukuzawa, Kunihiko Kiuchi, Hideya Suehiro, Tomomi Akita, Makoto Takemoto, Toshihiro Nakamura, Jun Sakai, Atsusuke Yatomi, Kazutaka Nakasone, Yusuke Sonoda, Kyoko Yamamoto, Hiroyuki Takahara, and Ken‐ichi Hirata
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carbon ion beam ,electrophysiology ,proton beam ,radiation ,ventricular arrhythmia ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Medium‐dose (25 gray) x‐ray radiation therapy has recently been performed on patients with refractory ventricular tachyarrhythmias. Unlike x‐ray, carbon ion and proton beam radiation can deliver most of their energy to the target tissues. This study investigated the electrophysiological and pathological changes caused by medium‐dose carbon ion and proton beam radiation in the left ventricle (LV). Methods and Results External beam radiation in the whole LV was performed in 32 rabbits. A total of 9 rabbits were not irradiated (control). At the 3‐month or 6‐month follow‐up, the animals underwent an open‐chest electrophysiological study and were euthanized for histological analyses. No acute death occurred. Significant LV dysfunction was not seen. The surface ECG revealed a significant reduction in the P and QRS wave voltages in the radiation groups. The electrophysiological study showed that the local conduction times in each LV site were significantly longer and that the local LV bipolar voltages were significantly lower in the radiation groups than in the control rabbits. Histologically, apoptosis, fibrotic changes, and a decrease in the expression of the connexin 43 protein were seen in the LV myocardium. These changes were obvious at 3 months, and the effects were sustained 6 months after radiation. No histological changes were seen in the coronary artery and esophagus, but partial radiation pneumonitis was observed. Conclusions Medium‐dose carbon ion and proton beam radiation in the whole LV resulted in a significant electrophysiological disturbance and pathological changes in the myocardium. Radiation of the arrhythmogenic substrate would modify the electrical status and potentially induce the antiarrhythmic effect.
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- 2021
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17. The limitations and potential adverse effects of the premature ventricular contraction response
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Hiroki Konishi, Koji Fukuzawa, Shumpei Mori, Kunihiko Kiuchi, and Ken‐ichi Hirata
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pacemaker ,pacemaker mediated tachycardia ,premature ventricular contraction response ,ventricular pacing on T‐wave ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract A 69‐year‐old man, who had undergone surgery for mitral and tricuspid regurgitation with the Maze procedure for paroxysmal atrial fibrillation, was admitted with an episode of syncope due to sick sinus syndrome. Three days after implantation of a dual‐chamber pacemaker (Accent MRI™, St. Jude Medical Inc.,), ventricular pacing on T‐wave was recorded multiple times. St. Jude Medical Inc. pacemakers have a unique additional algorithm, called premature ventricular contraction response, related to preventing pacemaker‐mediated tachycardia. This algorithm was determined to be a cause of ventricular pacing on T‐wave. We report the limitations and potential adverse effects of such automated algorithms.
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- 2018
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18. The lesion characteristics assessed by LGE‐MRI after the cryoballoon ablation and conventional radiofrequency ablation
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Jun Kurose, Kunihiko Kiuchi, Koji Fukuzawa, Shumpei Mori, Hirotoshi Ichibori, Hiroki Konishi, Yayoi Taniguchi, Kiyohiro Hyogo, Hiroshi Imada, Hideya Suehiro, Yu‐ichi Nagamatsu, Tomomi Akita, Makoto Takemoto, Ken‐ichi Hirata, Shinsuke Shimoyama, Yoshiaki Watanabe, Tatsuya Nishii, Noriyuki Negi, and Katsusuke Kyotani
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atrial fibrillation ,cryoballoon ablation ,late gadolinium enhancement MRI ,pulmonary vein isolation ,radiofrequency ablation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Rhythm outcomes after the pulmonary vein isolation (PVI) using the cryoballoon (CB) are reported to be excellent. However, the lesions after CB ablation have not been well discussed. We sought to characterize and compare the lesion formation after CB ablation with that after radiofrequency (RF) ablation. Methods A total of 42 consecutive patients who underwent PVI were enrolled (29 in the CB group and 13 in the RF group). The PVI lesions were assessed by late gadolinium enhancement magnetic resonance imaging 1–3 months after the PVI. The region around the PVs was divided into eight segments: roof, anterior‐superior, anterior‐carina, anterior‐inferior, bottom, posterior‐inferior, posterior‐carina, and posterior‐superior segment. The lesion width and lesion gap in each segment were compared between the two groups. Lesion gaps were defined as no‐enhancement sites of >4 mm. Results As compared to the RF group, the overall lesion width was significantly wider and lesion gaps significantly fewer at the anterior‐superior segment of the left PV (LAS) and anterior‐inferior segment of the right PV (RAI) in the CB group (lesion width: 8.2 ± 2.2 mm vs 5.6 ± 2.0 mm, P = .001; lesion gap at LAS: 7% vs 38%, P = .02; lesion gap at RAI: 7% vs 46%, P = .006). Conclusions The PVI lesions after CB ablation were characterized by extremely wider and more continuous lesions than those after RF ablation.
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- 2018
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19. Anatomical dilatation of the superior vena cava associated with an arrhythmogenic response induced by SVC scan pacing after atrial fibrillation ablation
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Hiroshi Imada, M.D., Koji Fukuzawa, M.D., Kunihiko Kiuchi, M.D., F.H.R.S., Akinori Matsumoto, M.D., Hiroki Konishi, M.D., Hirotoshi Ichibori, M.D., Kiyohiro Hyogo, M.D., Jun Kurose, M.D., Shumpei Mori, M.D., Tomofumi Takaya, M.D., Tatsuya Nishii, M.D., Kiyosumi Kagawa, R.T., Akihiro Yoshida, MD., and Hirata Ken-ichi, M.D.
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Superior vena cava ,Scan pacing ,Arrhythmogenic response ,Atrial fibrillation ,Catheter ablation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: The relationship between pulmonary vein (PV) arrhythmogenicity and its anatomy has been reported. However, that of the superior vena cava (SVC) has not been well discussed. Arrhythmogenic response induced by pacing stimulation at SVC might help with identifying SVC arrhythmogenicity. The purpose of this study was to investigate the relationship between the anatomical dilatation of SVC and the arrhythmogenic response induced by pacing at SVC. Methods: Forty-three patients who underwent atrial fibrillation (AF) ablation were enrolled in this study. After PV isolation, scan pacing (up to triple extra stimulation following intrinsic sinus beats) was performed at SVC. The arrhythmogenic response was defined as following: (1) repetitive atrial responses, (2) non-sustained, and (3) sustained AF/ atrial tachycardia. To assess the dilatation of SVC, we measured the cross-sectional area of the SVC (SVC-area) using multi-planar reconstruction CT imaging. Results: Arrhythmogenic responses were documented in 24 patients (Group 1). No arrhythmogenic responses were documented in the remaining 19 patients (Group 2). The SVC-area was significantly larger in Group 1 than Group 2 (3.1±0.9 vs. 2.2±0.8 cm2, P=0.004). A multivariate analysis revealed only SVC-area was associated with arrhythmogenic responses (odds ratio=2.87, CI 1.05–7.82, P=0.04). Furthermore, AF recurrence rate was significantly higher in patients with SVC-area>2.56 cm2 than those with SVC-area
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- 2017
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20. The details of an unusual âghostâ after transvenous lead extraction: Three-dimensional computed tomography analysis
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Kunihiko Kiuchi, MD, FHRS, Koji Fukuzawa, MD, Shumpei Mori, MD, Tatsuya Nishii, MD, Kensuke Matsumoto, MD, Hirotoshi Ichibori, MD, and Takashi Yamada, MD
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Transvenous lead extraction (TLE) is performed to prevent deaths in patients with device infections. Intracardiac masses detected by echocardiography, i.e., âghosts,â are reported in 8% of patients after a TLE in retrospective studies and in 14% in prospective studies. We herein describe a case with unusual ghosts after a TLE. Three-dimensional computed tomography (3DCT) is useful for revealing all the details of unusual ghosts. In this case, the residual silicone insulation and âcast,â including the fibrous sheath and severe calcifications could be visualized and differentiated by 3DCT. Keywords: Transvenous lead extraction, Cardiac rhythm device, Device infection, Computed tomography
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- 2017
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21. Extracardiac compression of the inferolateral branch of the coronary vein by the descending aorta in a patient with dilated cardiomyopathy
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Hiroki Konishi, MD, PhD, Shumpei Mori, MD, PhD, Tatsuya Nishii, MD, PhD, Yu Izawa, MD, Naoki Tamada, MD, Hidekazu Tanaka, MD, PhD, Kunihiko Kiuchi, MD, PhD, Koji Fukuzawa, MD, PhD, and Ken-ichi Hirata, MD, PhD
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Extracardiac structures can cause distortion of cardiac anatomy particularly in patients presenting with a significantly dilated heart, and/or thoracic deformities. We present the case of a 69-year-old woman with dilated cardiomyopathy who underwent cardiac resynchronization therapy. Preoperative electrocardiography-gated contrast-enhanced computed tomography revealed the inferolateral wall of her significantly dilated and leftward-rotated heart was close to the descending aorta, and the descending aorta compressed the sandwiched inferolateral branch of the coronary vein. Retrograde coronary venography performed at the time of device implantation confirmed focal stenosis of the inferolateral branch of the coronary vein. Keywords: Cardiac resynchronization therapy, Computed tomography, Dilated cardiomyopathy
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- 2017
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22. Impact of esophageal temperature monitoring guided atrial fibrillation ablation on preventing asymptomatic excessive transmural injury
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Kunihiko Kiuchi, MD, FHRS, Katsunori Okajima, MD, Akira Shimane, MD, Gaku Kanda, MD, Kiminobu Yokoi, MD, Jin Teranishi, MD, Kousuke Aoki, MD, Misato Chimura, MD, Takayoshi Toba, MD, Shogo Oishi, MD, Takahiro Sawada, MD, Yasue Tsukishiro, MD, Tetsuari Onishi, MD, Seiichi Kobayashi, MD, Yasuyo Taniguchi, MD, Shinichiro Yamada, MD, Yoshinori Yasaka, MD, Hiroya Kawai, MD, Akihiro Yoshida, MD, Koji Fukuzawa, MD, Mitsuaki Itoh, MD, Kimitake Imamura, MD, Ryudo Fujiwara, MD, Atsushi Suzuki, MD, Tomoyuki Nakanishi, MD, Soichiro Yamashita, MD, Ken-ichi Hirata, MD, Hiroshi Tada, MD, FHRS, Hiro Yamasaki, MD, Yoshihisa Naruse, MD, Miyako Igarashi, MD, and Kazutaka Aonuma, MD
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Esophageal injury ,Periesophageal nerve injury ,Esophageal temperature monitoring ,Catheter ablation ,Atrial fibrillation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Even with the use of a reduced energy setting (20–25 W), excessive transmural injury (ETI) following catheter ablation of atrial fibrillation (AF) is reported to develop in 10% of patients. However, the incidence of ETI depends on the pulmonary vein isolation (PVI) method and its esophageal temperature monitor setting. Data comparing the incidence of ETI following AF ablation with and without esophageal temperature monitoring (ETM) are still lacking. Methods: This study was comprised of 160 patients with AF (54% paroxysmal, mean: 24.0±2.9 kg/m2). Eighty patients underwent ablation accompanied by ETM. The primary endpoint was defined as the occurrence of ETI assessed by endoscopy within 5 d after the AF ablation. The secondary endpoint was defined as AF recurrence after a single procedure. If the esophageal temperature probe registered >39 °C, the radiofrequency (RF) application was stopped immediately. RF applications could be performed in a point-by-point manner for a maximum of 20 s and 20 W. ETI was defined as any injury that resulted from AF ablation, including esophageal injury or periesophageal nerve injury (peri-ENI). Results: The incidence of esophageal injury was significantly lower in patients whose AF ablation included ETM compared with patients without ETM (0 [0%] vs. 6 [7.5%], p=0.028), but not the incidence of peri-ENI (2 [2.5%] vs. 3 [3.8%], p=1.0). AF recurrence 12 months after the procedure was similar between the groups (20 [25%] in the ETM group vs. 19 [24%] in the non-ETM group, p=1.00). Conclusions: Catheter ablation using ETM may reduce the incidence of esophageal injury without increasing the incidence of AF recurrence but not the incidence of peri-ENI.
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- 2016
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23. The inferior displacement of the His bundle and fast pathway in a patient with common type atrioventricular nodal tachycardia: Three-dimensional computed tomography analysis
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Kunihiko Kiuchi, MD, FHRS, Koji Fukuzawa, MD, Mori Shumpei, MD, and Tatsuya Nishii, MD
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AVNRT ,Fast pathway ,His bundle ,Catheter ablation ,Computed tomography ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
A 66-year-old woman with palpitations was referred to our center for catheter ablation due to drug-refractory, common type atrioventricular nodal tachycardia (AVNRT). A selective slow pathway ablation was attempted. A fast junctional rhythm with transient ventriculoatrial block followed by transient prolongation of the A–H interval occurred immediately after the radiofrequency (RF) application at the coronary sinus ostium (CSOS) level. To assess the location of the fast pathway and His bundle, we sought to visualize the anatomy of the triangle of Koch (TOK) by three-dimensional computed tomography (CT).
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- 2017
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24. Topographic variability of the left atrium and pulmonary veins assessed by 3D-CT predicts the recurrence of atrial fibrillation after catheter ablation
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Kunihiko Kiuchi, MD, Akihiro Yoshida, MD, Asumi Takei, MD, Koji Fukuzawa, MD, Mitsuaki Itoh, MD, Kimitake Imamura, MD, Ryudo Fujiwara, MD, Atsushi Suzuki, MD, Tomoyuki Nakanishi, MD, Soichiro Yamashita, MD, Ken-ichi Hirata, MD, Gaku Kanda, MD, Katsunori Okajima, MD, Akira Shimane, MD, Shinichiro Yamada, MD, Yasuyo Taniguchi, MD, Yoshinori Yasaka, MD, and Hiroya Kawai, MD
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Computed tomography ,Left atrium ,Pulmonary vein ,Atrial fibrillation ,Catheter ablation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Catheter ablation (CA) is an established therapy for atrial fibrillation (AF). However, the assessment of anatomical information and predictors of AF recurrence remain unclear. We investigated the relationship between anatomical information on the left atrium (LA) and pulmonary veins (PVs) from three-dimensional computed tomography images and the recurrence of AF after CA. Methods: Sixty-seven consecutive AF patients (mean age: 62±10 years, median AF history: 42 (12; 60) months, mean LA size: 41±7 mm, paroxysmal: 56%) underwent CA and were followed for 19±10 months. The segmented surface areas (antral, posterior, septal, and lateral) and dimensions (between the anterior and posterior walls, the right inferior PV and mitral annulus [MA], the right superior PV and MA, the left superior PV and MA, and the mitral isthmus) of the LA were evaluated three dimensionally using the NavX system. The cross-sectional areas of the PVs were also evaluated. Results: After the follow-up period, 49 patients (73%) remained free from AF. A multivariate analysis showed that the diameter of the mitral isthmus and cross-sectional area of the right upper PV were associated with AF recurrence (odds ratio: 1.070, CI: 1.02–1.12, p=0.001; odds ratio: 0.41, CI: 0.21–0.77, p=0.006). Conclusion: Enlargement of the mitral isthmus and a smaller right superior PV cross-sectional area were associated with AF recurrence.
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- 2015
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25. The effectiveness of cardiac resynchronization therapy for patients with New York Heart Association class IV non-ambulatory heart failure
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Soichiro Yamashita, MD, Koji Fukuzawa, MD, Akihiro Yoshida, MD, Mitsuaki Itoh, MD, Kimitake Imamura, MD, Ryudo Fujiwara, MD, Atsushi Suzuki, MD, Tomoyuki Nakanishi, MD, Akinori Matsumoto, MD, Gaku Kanda, MD, Kunihiko Kiuchi, MD, Akira Shimane, MD, Katsunori Okajima, MD, Hidekazu Tanaka, MD, and Ken-ichi Hirata, MD
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Cardiac resynchronization therapy ,NYHA IV ,Heart failure ,Radial strain dyssynchrony ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: We reviewed the effectiveness and safety of cardiac resynchronization therapy (CRT) for patients with New York Heart Association (NYHA) class IV non-ambulatory heart failure (NAHF). Methods: From 2006 to 2011, 310 patients underwent CRT at Kobe University Hospital and Himeji Cardiovascular Center because of heart failure. Of these, 29 NAHF patients were retrospectively analyzed. The control group comprised 21 age- and ejection fraction-matched patients with NAHF who did not undergo CRT from the ICU database of Kobe University Hospital. The primary endpoint was all-cause death and hospitalization for heart failure. Response was defined as a >15% reduction in left ventricular end-systolic volume (LVESV). Results: CRT was performed successfully without serious complications in all patients. Twenty-three patients (79%) were discharged 19±15 days after CRT implantation, while 6 (21%) died during their hospital stay due to progressive heart failure. Compared with the control group, patients in the CRT group showed significant improvements in the primary endpoint (log-rank p=0.04). Six patients (21%) were defined as responders and the Kaplan–Meier curve showed that responders experienced a better outcome than non-responders (log-rank p=0.029). LV dyssynchrony before implantation was significantly related to the occurrence of the primary endpoint (p=0.02). Conclusions: CRT can be safely used in patients with NAHF and can improve long-term patient outcomes, especially in treatment responders.
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- 2015
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26. Prophylactic catheter ablation of ventricular tachycardia before cardioverter-defibrillator implantation in patients with non-ischemic cardiomyopathy: Clinical outcomes after a single endocardial ablation
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Atsushi Suzuki, MD, Akihiro Yoshida, MD, PhD, Asumi Takei, MD, PhD, Koji Fukuzawa, MD, PhD, Kunihiko Kiuchi, MD, PhD, Kaoru Takami, MD, Mitsuaki Itoh, MD, PhD, Kimitake Imamura, MD, PhD, Ryudo Fujiwara, MD, PhD, Tomoyuki Nakanishi, MD, Soichiro Yamashita, MD, Akinori Matsumoto, MD, Akira Shimane, MD, Katsunori Okajima, MD, PhD, and Ken-ichi Hirata, MD, PhD
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Catheter ablation ,Ventricular tachycardia ,Implantable cardioverter-defibrillator ,Non-ischemic cardiomyopathy ,Electrical storm ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Outcomes related to prophylactic catheter ablation (PCA) for ventricular tachycardia (VT) before implantable cardioverter-defibrillator (ICD) implantation in non-ischemic cardiomyopathy (NICM) are not well characterized. We assessed the efficacy of single endocardial PCA in NICM patients. Methods: We retrospectively analyzed 101 consecutive NICM patients with sustained VT. We compared clinical outcomes of patients who underwent PCA (ABL group) with those who did not (No ABL group). Successful PCA was defined as no inducible clinical VT. We also compared the clinical outcomes of patients with successful PCA (PCA success group) with those of the No ABL group. Endpoints were appropriate ICD therapy (shock and anti-tachycardia pacing) and the occurrence of electrical storm (ES). Results: PCA was performed in 42 patients, and it succeeded in 20. The time to ES occurrence was significantly longer in the ABL group than in the No ABL group (p=0.04). The time to first appropriate ICD therapy and ES occurrence were significantly longer in the PCA success group than in the No ABL group (p=0.02 and p
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- 2015
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27. Anatomical consideration for safe pericardiocentesis assessed by three-dimensional computed tomography: Should an anterior or posterior approach be used?
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Jin Teranishi, MD, Katsunori Okajima, MD, Kunihiko Kiuchi, MD, Akira Shimane, MD, Koji Fukuzawa, MD, Gaku Kanda, MD, Kiminobu Yokoi, MD, Shinichiro Yamada, MD, Yasuyo Taniguchi, MD, Yoshinori Yasaka, MD, and Hiroya Kawai, MD
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Pericardiocentesis ,Catheter ablation ,Ventricular tachyarrhythmia ,Computed tomography ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: The efficacy of epicardial catheter ablation for ventricular tachycardia has been reported. However, the safest anatomical method for pericardial puncture has not been determined. Methods: Thirty patients who underwent 3-dimensional computed tomography (3D-CT) preceding catheter ablations for atrial fibrillation were enrolled in this study. We used the skin surface 1 cm below the xiphisternum as the puncture site. For the anterior approach, the attainment site was the pericardium of the mid portion of right ventricular anterior site, and for the posterior approach it was the pericardium of the inferior ventricular site. The distance and the angle between the 2 sites were measured using 3D-CT. Results: For the anterior approach, the distance was 54±11 mm and the needle angle was 37±11° toward the left scapula and 34±12° towards the back of the body. For the posterior approach, the distance was 56±10 mm and the corresponding needle angles were 60±9° and 86±13°. The distance correlated with BMI for the anterior and posterior approaches (anterior approach: r2=0.43, P
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- 2014
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28. Eccentric scar formation around a pulmonary vein after cryo-balloon ablation in a patient with atrial fibrillation: A case report
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Kunihiko Kiuchi, MD, FHRS, Koji Fukuzawa, MD, and Akinori Matsumoto, MD
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Delayed enhancement magnetic resonance imaging ,Cryoballoon ,Ablation ,Atrial fibrillation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
The impact of a cryoballoon ablation is reported to be similar to that of a radiofrequency (RF) ablation in patients with atrial fibrillation. Delayed enhancement magnetic resonance imaging (DE-MRI) could visualize the scar region induced by the cryoballoon ablation as well as RF ablation. Cryoballoon ablation could induce extensive scar lesions around the PVs. However, the distribution of the scar lesions after the cryoballoon ablation has not been well discussed. We, herein, described a case with an eccentric scar distribution after cryoballoon ablation.
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- 2016
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29. 'Heparin bridging' increases the risk of bleeding complications in patients undergoing anticoagulation therapy and device implantation
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Ryudo Fujiwara, Akihiro Yoshida, Asumi Takei, Koji Fukuzawa, Kaoru Takami, Mitsuru Takami, Satoko Tanaka, Mitsuaki Ito, Kimitake Imamura, and Ken-ichi Hirata
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Device implantation ,Bleeding complication ,Heparin bridging ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: The purpose of this study is to evaluate the rate of perioperative bleeding complications following anticoagulation therapy in patients undergoing implantable electronic device implantation. Methods and results: We retrospectively analyzed the data from 161 consecutive patients with new device implants or generator replacement performed between February 2008 and June 2009 in our hospital. Sixty-five (40.3%) patients took warfarin, 55 (34.2%) took antiplatelet therapy, and 16 (9.9%) took dual antiplatelet therapy prior to implantation. Heparin bridging was performed in 7 of 65 patients taking warfarin. Pocket hematoma was observed in 10 (6.2%) patients and device infection was observed in 1 (0.6%) patient. No cases of thromboembolism were observed. There were no complications associated with warfarin (P=0.19) or antiplatelet therapy (P=0.69). However, the patients that had undergone heparin bridging were significantly more likely to have complications (3 of 10) (P=0.005). In multivariate analysis, heparin bridging was the only independent predictor of complications. Conclusion: Our study suggests that heparin bridging increases the risk of perioperative bleeding complications in cardiac device implantation.
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- 2012
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30. Revisiting the Anatomy of the Left Ventricular Summit
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Shumpei Mori, Justin Hayase, Aadhavi Sridharan, Koji Fukuzawa, Kalyanam Shivkumar, and Jason S. Bradfield
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Published
- 2023
31. The impact of the procedural parameters on the lesion characteristics associated with AF recurrence: Late‐gadolinium enhancement magnetic resonance imaging (LGE‐MRI) analysis
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Hiroyuki Takahara, Kunihiko Kiuchi, Koji Fukuzawa, Mitsuru Takami, Yu Izawa, Toshihiro Nakamura, Kazutaka Nakasone, Yusuke Sonoda, Kyoko Yamamoto, Yuya Suzuki, Ken‐ichi Tani, Hidehiro Iwai, Yusuke Nakanishi, Mitsuhiko Shoda, Atsushi Murakami, Shogo Yonehara, Noriyuki Negi, Yuichiro Somiya, and Ken‐ichi Hirata
- Subjects
Physiology (medical) ,Cardiology and Cardiovascular Medicine - Abstract
Lesion gaps assessed by late-gadolinium enhancement magnetic resonance imaging (LGE-MRI) are associated with the atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). Animal studies have demonstrated that the catheter-contact force (CF), stability, and orientation are strongly associated with lesion formation. However, the impact of those procedural factors on the lesion characteristics associated with AF recurrence has not been well discussed.A total of 30 patients with paroxysmal AF who underwent catheter ablation were retrospectively enrolled. Radiofrequency (RF) applications were performed with 35W for 30s in a point-by-point fashion under esophageal temperature monitoring. The inter-lesion distance was 4mm. The lesions were visualized by LGE-MRI three months post-procedure and assessed by the LGE volume (ml), gap number (GN), and average gap length (AGL [mm]). The gaps were defined as non-enhancement sites of4 mm. The procedural factors including the catheter-CF, stability, and orientation were calculated on the NavX system.Six (20%) of 30 patients had AF recurrences 12 months post-ablation. A univariate analysis demonstrated that the AGL was associated with AF recurrence (hazard ratio [HR]: 1.20, confidence interval [CI]:1.03 - 1.42, p = 0.02). All AF recurrence were found in patients with an AGL of7 mm. The catheter-CF and stability were associated with an AGL of7mm, but not the orientation (CF: HR: 0.62, CI: 0.39-0.97, p=0.038; stability: HR: 0.8, CI: 0.66-0.98, p=0.027).RF ablation with a low CF and poor catheter stability has a potential risk of creating large lesion gaps associated with AF recurrence. This article is protected by copyright. All rights reserved.
- Published
- 2023
32. Sex Differences in the Regional Analysis of Nonpulmonary Vein Foci and Epicardial Adipose Tissue in Patients With Atrial Fibrillation
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Jun, Sakai, Mitsuru, Takami, Koji, Fukuzawa, Kunihiko, Kiuchi, Toshihiro, Nakamura, Atsusuke, Yatomi, Yusuke, Sonoda, Hiroyuki, Takahara, Kazutaka, Nakasone, Kyoko, Yamamoto, Yuya, Suzuki, Kenichi, Tani, Hidehiro, Iwai, Yusuke, Nakanishi, and Ken-Ichi, Hirata
- Subjects
Male ,Sex Characteristics ,Atrial fibrillation recurrence ,General Medicine ,Treatment Outcome ,Adipose Tissue ,Recurrence ,Pulmonary Veins ,Atrial Fibrillation ,Epicardial adipose tissue ,Sex differences ,Catheter Ablation ,Humans ,Female ,Heart Atria ,Cardiology and Cardiovascular Medicine ,Non-PV foci - Abstract
Background: The mechanism underlying the sex differences in atrial fibrillation (AF) recurrence following pulmonary vein (PV) isolation is not fully understood. We hypothesized that non-PV foci and epicardial adipose tissue (EAT) play a key role. Methods and Results: Data from 304 consecutive patients (75% males) who underwent contrast-enhanced computed tomography and catheter ablation of AF were reviewed. The EAT around the atrium was measured separately in 4 parts of the atrium. All patients underwent high-dose isoproterenol infusions to assess the non-PV foci. Significantly more non-PV foci and less EAT around the atrium were observed in female patients than in male patients. In males, those with non-PV foci on the left atrial (LA) anterior wall had significantly greater EAT for the same lesions than those without non-PV foci. During a median follow-up of 27 months, the predictors of AF recurrence after first catheter ablation were female sex, presence of non-PV foci, LA diameter, and septal EAT index. A sex-specific analysis revealed that LA diameter was a predictor only in males and that the presence of non-PV foci in the septal region was a strong predictor in males (hazard ratio [HR]: 2.24) and females (HR: 3.65). Conclusions: Sex-specific differences were observed in non-PV foci sites and local EAT and in regard to the predictors of AF recurrence.
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- 2022
33. Factors related to the skin thicknessof cardiovascular implantable electronic device pockets
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Atsusuke Yatomi, Mitsuru Takami, Koji Fukuzawa, Kunihiko Kiuchi, Jun Sakai, Toshihiro Nakamura, Yusuke Sonoda, Hiroyuki Takahara, Kazutaka Nakasone, Kyoko Yamamoto, Yuya Suzuki, Kenichi Tani, Hidehiro Iwai, Yusuke Nakanishi, and Ken‐ichi Hirata
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Heart Failure ,Pacemaker, Artificial ,Prosthesis-Related Infections ,skin thickness ,device erosion ,Stroke Volume ,Ventricular Function, Left ,Defibrillators, Implantable ,Physiology (medical) ,device infection ,Humans ,Female ,Electronics ,Cardiology and Cardiovascular Medicine ,cardiovascular implantable electronic devices ,device pocket ,Retrospective Studies - Abstract
The skin overlying cardiovascular implantable electronic devices (CIEDs) sometimes becomes very thin after implantations, which could cause a device erosion. The factors related to the skin thickness of device pockets have not been elucidated. This study aimed to evaluate the skin thickness of CIED pockets and search for the factors associated with the thickness.Seventeen skin thickness points around the CIED pocket were measured through ultrasonography in each patient.A total of 101 patients (76 ± 11 years, 26 female) were enrolled. The median duration from the implantation to the examination was 95 months (quartile: 52.5-147.5). The median skin thickness overlying the device was 4.1 mm (3.3-5.9). Patients with heart failure and malignancy had thinner skin overlying the CIED than those without. A significant correlation existed between skin thickness and body mass index (BMI), hemoglobin, serum creatinine, estimated glomerular filtration rate (eGFR), and left ventricular ejection fraction. In contrast, age, gender, and device size did not exhibit a significant correlation with skin thickness. A multivariate logistic regression analysis revealed that chronic heart failure and a decrease in the eGFR and BMI were independent predictive factors of "very thin (≦3.3 mm)" skin of the CIED pocket late after an implantation.Aside from a low BMI, the comorbidities (low hemoglobin, heart failure, and renal dysfunction) had a stronger impact on the skin thickness overlying the device than the device size. A careful observation of the device pocket should be performed in patients with those risk factors.
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- 2022
34. Very late perforation of a passive fixation lead 8 years after pacemaker implantation
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Hidehiro Iwai, Mitsuru Takami, Koji Fukuzawa, Hidekazu Nakai, Kenji Okada, and Ken-ichi Hirata
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Cardiology and Cardiovascular Medicine - Published
- 2023
35. Characteristics of non-valvular atrial fibrillation with left atrial appendage thrombus who are undergoing appropriate oral anticoagulation therapy
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Hiroaki Shiraki, Hidekazu Tanaka, Yuki Yamauchi, Yuko Yoshigai, Kentaro Yamashita, Yusuke Tanaka, Keiko Sumimoto, Ayu Shono, Makiko Suzuki, Shun Yokota, Kensuke Matsumoto, Koji Fukuzawa, and Ken-ichi Hirata
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anticoagulants ,left atrial appendage ,Radiology, Nuclear Medicine and imaging ,Cardiology and Cardiovascular Medicine ,Non-valvular atrial fibrillation ,Transesophageal echocardiography ,Thrombus ,left atrium - Abstract
We investigated the characteristics of patients with non-valvular atrial fibrillation (NVAF) and left atrial (LA) appendage (LAA) thrombus who had been given appropriate oral anticoagulation therapy. We studied 737 NVAF patients who were scheduled for catheter ablation or electrical cardioversion. All patients received appropriate oral anticoagulation therapy for at least 3 weeks prior to echocardiography in accordance with the guidelines. Whether LAA thrombus was present or absent on transesophageal echocardiography (TEE) was determined by at least three senior echocardiologists. LAA thrombi were observed in 22 patients (3.0%). Multivariate logistic regression analysis showed that LAA flow and LA volume index were both independent predictors of LAA thrombus formation; however, LAA flow (≤ 18 cm/s) was indicated as a more powerful predictor. Moreover, the prevalence of LAA thrombus formation in patients with NVAF without LA enlargement (LA volume index ≤ 34 mL/m2) was extremely rare (0.4%). LAA thrombus formation in patients with a mildly dilated LA volume index of 34–49.9 mL/m2 and paroxysmal AF was also extremely rare (0.0%). LAA flow is strongly associated with LAA thrombus formation, even in NVAF patients treated with appropriate oral anticoagulation therapy. Augmented oral anticoagulation therapy or transcatheter or surgical LAA closure should be considered for such patients, especially for those with an LAA flow
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- 2022
36. Ultrasound-guided intermuscular pocket creation for a subcutaneous implantable cardioverter-defibrillator
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Jun Sakai, Koji Fukuzawa, Yusuke Sonoda, Yu Izawa, and Ken-ichi Hirata
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medicine.medical_specialty ,Serratus anterior muscle ,business.industry ,medicine.medical_treatment ,Latissimus dorsi muscle ,Ultrasound ,medicine.disease ,Implantable cardioverter-defibrillator ,Ultrasound guided ,Sudden cardiac death ,Defibrillation threshold ,Internal medicine ,Ventricular fibrillation ,medicine ,Cardiology ,Cardiology and Cardiovascular Medicine ,business - Published
- 2022
37. Ventricular tachycardia based on cardiac sarcoidosis with a narrow QRS complex, ablated on the left ventricle free-wall
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Yu Izawa, Ken-ichi Hirata, Kunihiko Kiuchi, Hiroshi Imada, and Koji Fukuzawa
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medicine.medical_specialty ,medicine.medical_treatment ,Case Report ,Catheter ablation ,030204 cardiovascular system & hematology ,Narrow QRS complex ,Ventricular tachycardia ,03 medical and health sciences ,QRS complex ,0302 clinical medicine ,Cardiac sarcoidosis ,Physiology (medical) ,Internal medicine ,Medicine ,Diseases of the circulatory (Cardiovascular) system ,Sinus rhythm ,030212 general & internal medicine ,cardiovascular diseases ,business.industry ,medicine.disease ,Ablation ,Electrophysiology ,medicine.anatomical_structure ,Ventricle ,RC666-701 ,Cardiology ,cardiovascular system ,Cardiology and Cardiovascular Medicine ,business - Abstract
A septuagenarian female with cardiac sarcoidosis suffered from drug refractory ventricular tachycardia (VT) requiring multiple implantable cardioverter-defibrillator shocks. The QRS complex during the VT was very similar to that during sinus rhythm although the QRS width during the VT (142 ms) was relatively wider than that during sinus rhythm (107 ms). The VT exit was located on the ventricular septum close to the His-bundle recording region. However, the critical pathway of this VT was detected on the anterior free wall of the left ventricle (LV), and a radiofrequency application at that site could terminate the VT. No Purkinje potentials were recorded there during the VT or sinus rhythm. According to the electrophysiological study, 3-D mapping, and the response to the ablation, the critical circuit of the VT was surrounded by a protected area of scar associated with cardiac sarcoidosis. As a result, the VT circuit was connected to the basal septal area close to the His-Purkinje system as an outer loop of the VT circuit. This unique trajectory of the VT might have caused a similar QRS morphology to that of sinus rhythm, and the relatively narrow QRS complex despite the critical isthmus was located on the anterior free wall of the LV.
- Published
- 2021
38. Practical Utility of the Postal Service in Delivering a Self-Fitted, Wearable, Long-Term Electrocardiogram Monitoring Device for Outpatient Care
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Yusuke Sonoda, Makoto Takemoto, Kenichi Tani, Kunihiko Kiuchi, Kazutaka Nakasone, Koji Fukuzawa, Mitsuru Takami, Kyoko Yamamoto, Yuya Suzuki, Hiroyuki Takahara, Jun Sakai, Toshihiro Nakamura, Atsusuke Yatomi, and Ken-ichi Hirata
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Coronavirus disease 2019 (COVID-19) ,business.industry ,Wearable computer ,Monitoring system ,General Medicine ,medicine.disease ,Postal delivery ,Term (time) ,Ecg monitoring ,Clinical Practice ,Ambulatory care ,Postal service ,Medicine ,Medical emergency ,cardiovascular diseases ,business ,Rapid Communication ,Remote ECG monitoring - Abstract
Background: Demand is growing for remote electrocardiogram (ECG) monitoring systems in the COVID-19 era in Japan. This study describes initial experiences with a small wireless ECG monitoring device and the utility of delivery via the postal service for outpatient care in Japan. Methods and Results: Long-term ECG monitoring following postal delivery of the small ECG device was evaluated in 25 patients. The patients had no difficulties with either the postal delivery or self-fitting and wearing the devices. A median of 57 h monitoring per patient was performed. Arrhythmic events were detected in 8 patients. Most patients were satisfied with both the ECG devices and postal delivery. Conclusions: Postal delivery of ECG devices could be used in clinical practice to achieve less or no in-person contact during the COVID-19 era.
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- 2021
39. Late‐gadolinium enhancement properties associated with atrial fibrillation rotors in patients with persistent atrial fibrillation
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Toshihiro Nakamura, Yoshiaki Watanabe, Takashi Ashihara, Makoto Takemoto, Atsushi K. Kono, Atsusuke Yatomi, Kyoko Yamamoto, Mitsuru Takami, Hiroyuki Takahara, Kazutaka Nakasone, Ken-ichi Hirata, Kunihiko Kiuchi, Hideya Suehiro, Koji Fukuzawa, Jun Sakai, Noriyuki Negi, Yu Izawa, Yusuke Sonoda, and Tomomi Akita
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Contrast Media ,Gadolinium ,Catheter ablation ,030204 cardiovascular system & hematology ,Pulmonary vein ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,Atrial Fibrillation ,Humans ,Medicine ,Late gadolinium enhancement ,In patient ,Heart Atria ,cardiovascular diseases ,030212 general & internal medicine ,Antrum ,Receiver operating characteristic ,business.industry ,Atrial fibrillation ,medicine.disease ,Magnetic Resonance Imaging ,embryonic structures ,Persistent atrial fibrillation ,Catheter Ablation ,Cardiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background A computational model demonstrated that atrial fibrillation (AF) rotors could be distributed in patchy late-gadolinium enhancement (LGE) areas and play an important role in AF drivers. However, this was not validated in humans. Objective The purpose of this study was to evaluate the LGE area properties of AF rotors in patients with persistent AF. Methods A total of 287 segments in 15 patients with persistent AF (longstanding persistent AF in 9 patients) that underwent AF ablation were assessed. Non-passively activated areas (NPAs), where rotational activation (AF rotor) was frequently observed, were detected by the novel real-time phase mapping (ExTRa Mapping). The properties of the LGE areas were assessed using the LGE heterogeneity, and the density was assessed by the entropy (LGE-entropy) and volume ratio of the enhancement voxel (LGE-volume ratio), respectively. Results NPAs were found in 61 (21%) of 287 segments and were mostly found around the pulmonary vein antrum. A receiver operating characteristic curve analysis yielded an optimal cutoff value of 5.7 and 10% for the LGE-entropy and LGE-volume ratio, respectively. The incidence of NPAs was significantly higher at segments with an LGE-entropy of >5.7 and LGE-volume ratio of >10% than at the other segments (38 [30%] of 126 vs. 23 [14%] of 161 segments, p = 0.001). No NPAs were found at segments with an LGE-volume ratio of >50% regardless of the LGE-entropy. Of 5 patients with AF recurrence, NPAs outside the PV antrum were not ablated in 3 patients and the remaining NPAs were ablated, but their LGE-entropy and LGE-volume ratio were low. Conclusion AF rotors are mostly distributed in relatively weak and much more heterogenous LGE areas. This article is protected by copyright. All rights reserved.
- Published
- 2021
40. Circulating intermediate monocytes and atrial structural remodeling associated with atrial fibrillation recurrence after catheter ablation
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Naofumi Yoshida, Koji Fukuzawa, Hideya Suehiro, Tomoya Yamashita, Hiroyuki Takahara, Yu Izawa, Yoshiaki Watanabe, Yusuke Sonoda, Toshihiro Nakamura, Kyoko Yamamoto, Makoto Takemoto, Tomomi Akita, Jun Sakai, Ken-ichi Hirata, Mitsuru Takami, Kunihiko Kiuchi, Kazutaka Nakasone, and Atsusuke Yatomi
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,CD14 ,Contrast Media ,Gadolinium ,Catheter ablation ,030204 cardiovascular system & hematology ,Monocytes ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,hemic and lymphatic diseases ,Physiology (medical) ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,Heart Atria ,cardiovascular diseases ,030212 general & internal medicine ,Univariate analysis ,medicine.diagnostic_test ,Receiver operating characteristic ,Surrogate endpoint ,business.industry ,Magnetic resonance imaging ,Atrial fibrillation ,Atrial Remodeling ,Ablation ,medicine.disease ,Magnetic Resonance Imaging ,Catheter Ablation ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,human activities - Abstract
Background Inflammation, such as that associated with intermediate CD14++ CD16+ monocytes and atrial structural remodeling (SRM), may be important in the recurrence of atrial fibrillation (AF) after catheter ablation. However, the relationship between the intermediate CD14++ CD16+ monocytes, SRM, and AF recurrence is unclear. Methods Twenty-four patients with AF were enrolled. The proportion of intermediate monocytes (PIM) was assessed before ablation by flow cytometry. As a surrogate marker of SRM, the volume ratio (VR) of signal intensity greater than 1 standard deviation on late-gadolinium enhancement magnetic resonance imaging (LGE-MRI) was calculated. We investigated whether PIM correlated with SRM on LGE-MRI and determined the optimal cutoff value for predicting AF recurrence. Results Univariate analysis revealed positive correlations between PIM and BNP with SRM (PIM: r = .593, p = .002; BNP: r = .567, p = .004). Multivariable analysis revealed that PIM was independently associated with VR on LGE-MRI (β = .522; p = .033). The finding of an area under the receiver operating characteristic curve of 0.750 revealed that a VR ≥ 13.3% on LGE-MRI as the optimal cutoff value to predict AF recurrence with 80% sensitivity and 71% specificity, which was associated with PIM ≥ 10.0%. Conclusion Intermediate monocytes were significantly positively correlated with SRM. PIM ≥ 10% was associated with a VR ≥ 13.3% on LGE-MRI, which predicted AF recurrence after catheter ablation.
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- 2021
41. Feasibility of catheter ablation in patients with persistent atrial fibrillation guided by fragmented late‐gadolinium enhancement areas
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Tomomi Akita, Yoshiaki Watanabe, Katsusuke Kyotani, Koji Fukuzawa, Mayumi Shigeru, Kunihiko Kiuchi, Kazutaka Nakasone, Hiroyuki Takahara, Noriyuki Negi, Yusuke Sonoda, Hideya Suehiro, Jun Sakai, Toshihiro Nakamura, Atsusuke Yatomi, Mitsuru Takami, hiroyuki oonishi, Makoto Takemoto, Atsushi K. Kono, Ken-ichi Hirata, Kyoko Yamamoto, and Yu Izawa
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Contrast Media ,Gadolinium ,Catheter ablation ,030204 cardiovascular system & hematology ,Pulmonary vein ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,Physiology (medical) ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,Late gadolinium enhancement ,Computer Simulation ,In patient ,030212 general & internal medicine ,Atrial tachycardia ,Aged ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Atrial fibrillation ,Middle Aged ,medicine.disease ,Ablation ,Treatment Outcome ,Pulmonary Veins ,Catheter Ablation ,Cardiology ,Feasibility Studies ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Abstract
BACKGROUND: A computer simulation model has demonstrated that an atrial fibrillation (AF) driver can be attached to heterogeneous fibrosis assessed by late gadolinium enhancement magnetic resonance imaging (LGE-MRI). However, it has not been well elucidated in patients with persistent AF. The aim of this study was to investigate whether radiofrequency (RF) applications in the fragmented LGE area (FLA) could terminate AF or convert it to atrial tachycardia (AT) and improve the rhythm outcome. METHODS: A total of 31 consecutive persistent AF patients with FLAs were enrolled (FLA ablation group, mean age: 69 ± 8 years, mean left atrial diameter: 42 ± 6 mm). A favorable response was defined as direct AF termination or AT conversion during RF applications at the FLA. The rhythm outcome was compared between the FLA ablation group and FLA burden-matched pulmonary vein isolation (PVI) group. RESULTS: Favorable responses were found in 15 (48%) of 31 patients in the FLA group (AF termination in 7, AT conversion in 8 patients), but not in the PVI group. AF recurrence at 12 months follow-up was significantly less in the FLA ablation group than in the PVI group (4 [13%] vs. 12 [39%] of 31 patients, log-rank p=0.023). In patients with a favorable response, AT recurred in 1 (7%) of 15 patients but AF did not. CONCLUSIONS: FLA ablation could terminate AF or convert it to AT in half of the patients. No AF recurrence was documented in patients with a favorable response. This article is protected by copyright. All rights reserved.
- Published
- 2021
42. Ability of Left Atrial Distensibility After Radiofrequency Catheter Ablation to Predict Recurrence of Atrial Fibrillation
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Ayu Shono, Kensuke Matsumoto, Nao Ishii, Kenya Kusunose, Makiko Suzuki, Nao Shibata, Makiko Suto, Kumiko Dokuni, Mitsuru Takami, Kunihiko Kiuchi, Koji Fukuzawa, Hidekazu Tanaka, and Ken-ichi Hirata
- Subjects
Treatment Outcome ,Recurrence ,Atrial Fibrillation ,Catheter Ablation ,Humans ,Stroke Volume ,Atrial Remodeling ,Heart Atria ,Cardiology and Cardiovascular Medicine ,Ventricular Function, Left - Abstract
This study sought to assess the left atrial (LA) functional recovery after radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) and to evaluate the determining factor of procedural success of RFCA, using a novel preload stress echocardiography. A total of 111 patients with AF were prospectively recruited. The echocardiographic parameters were obtained during the leg-positive pressure (LPP) maneuver, both at baseline and midterm after RFCA. As an index of LA distensibility, the LA expansion index was calculated as (LAVsubmax/sub- LAVsubmin/sub) × 100 / LAVsubmin/sub. During a median follow-up period of 14.2 months, AF recurrence was observed in 23 patients (20.7%). In LA functional parameters at baseline, only the Δ LA expansion index was significantly larger in the success group (16 ± 11% vs 4 ± 9%, plt;0.05). At midterm follow-up, the Δ LA expansion index significantly increased to 32 ± 19% (plt;0.05), together with structural LA reverse remodeling only in the success group. Moreover, the Δ stroke volume index during the LPP stress test significantly increased only in the success group (from 2.3 ± 1.3 ml/msup2/supto 3.1 ± 4.8 ml/msup2/sup, plt;0.05). In a multivariate analysis, left ventricular ejection fraction (hazard ratio 0.911, plt;0.05) and baseline Δ LA expansion index (hazard ratio 0.827, plt;0.001) were independent predictors of AF recurrence. In conclusion, the baseline Δ LA expansion index during LPP stress is a reliable marker for predicting procedural success after RFCA. Moreover, maintenance of sinus rhythm resulted in an improvement of the preload reserve after RFCA.
- Published
- 2022
43. Development of a Visualization Deep Learning Model for Classifying Origins of Ventricular Arrhythmias
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Kazutaka Nakasone, Makoto Nishimori, Kunihiko Kiuchi, Masakazu Shinohara, Koji Fukuzawa, Mitsuru Takami, Mustapha El Hamriti, Philipp Sommer, Jun Sakai, Toshihiro Nakamura, Atsusuke Yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kyoko Yamamoto, Yuya Suzuki, Kenichi Tani, Hidehiro Iwai, Yusuke Nakanishi, and Ken-ichi Hirata
- Subjects
Electrocardiography ,Deep Learning ,Artificial Intelligence ,Heart Ventricles ,Ventricular arrhythmia ,Catheter Ablation ,Tachycardia, Ventricular ,Humans ,General Medicine ,Cardiology and Cardiovascular Medicine ,Ventricular Premature Complexes - Abstract
Background: Several algorithms have been proposed for differentiating the right and left outflow tracts (RVOT/LVOT) arrhythmia origins from 12-lead electrocardiograms (ECGs); however, the procedure is complicated. A deep learning (DL) model, a form of artificial intelligence, can directly use ECGs and depict the importance of the leads and waveforms. This study aimed to create a visualized DL model that could classify arrhythmia origins more accurately.Methods and Results: This study enrolled 80 patients who underwent catheter ablation. A convolutional neural network-based model that could classify arrhythmia origins with 12-lead ECGs and visualize the leads that contributed to the diagnosis using a gradient-weighted class activation mapping method was developed. The average prediction results of the origins by the DL model were 89.4% (88.2–90.6) for accuracy and 95.2% (94.3–96.2) for recall, which were significantly better than when a conventional algorithm is used. The ratio of the contribution to the prediction differed between RVOT and LVOT origins. Although leads V1 to V3 and the limb leads had a focused balance in the LVOT group, the contribution ratio of leads aVR, aVL, and aVF was higher in the RVOT group.Conclusions: This study diagnosed the arrhythmia origins more accurately than the conventional algorithm, and clarified which part of the 12-lead waveforms contributed to the diagnosis. The visualized DL model was convincing and may play a role in understanding the pathogenesis of arrhythmias.
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- 2022
44. Visualization of intensive atrial inflammation and fibrosis after cryoballoon ablation: PET/MRI and LGE‐MRI analysis
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Munenobu Nogami, Noriyuki Negi, Mitsuru Takami, Kunihiko Kiuchi, Yu Izawa, Ken-ichi Hirata, Shumpei Mori, Yoshiaki Watanabe, Katsusuke Kyotani, and Koji Fukuzawa
- Subjects
lcsh:Diseases of the circulatory (Cardiovascular) system ,medicine.medical_specialty ,cryoballoon ,Inflammation ,030204 cardiovascular system & hematology ,Pulmonary vein ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,Fibrosis ,Internal medicine ,medicine ,atrial fibrillation ,cardiovascular diseases ,030212 general & internal medicine ,Antrum ,medicine.diagnostic_test ,business.industry ,fibrosis ,Magnetic resonance imaging ,Atrial fibrillation ,Original Articles ,medicine.disease ,PET/MRI ,inflammation ,lcsh:RC666-701 ,Positron emission tomography ,cardiovascular system ,Cardiology ,Original Article ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background Atrial inflammation plays an important role in initiating atrial fibrosis, which could perpetuate atrial fibrillation (AF). However, the method of visualization of atrial inflammation has not been established. We sought to investigate whether the intensive atrial inflammation caused by cryoballoon ablation (CBA) could be detected by positron emission tomography/ magnetic resonance imaging (PET/MRI) and whether the atrial inflammation could be associated with consequent fibrosis. Methods A total of 10 paroxysmal atrial fibrillation patients after CBA were enrolled. To detect and quantify intensive atrial inflammation, PET/MRI was performed to assess regional 18F‐fluorodeoxyglucose (18F‐FDG) uptake one day after the CBA, and the standardized uptake values (SUV) max were compared between the pulmonary vein (PV) antrum where CBA could be applied and the healthy left atrial (LA) wall where CBA could not be applied. Furthermore, the atrial inflammation one day after the procedure and atrial fibrosis areas one month after the procedure were three‐dimensionally quantified by PET/MRI and late‐gadolinium enhancement magnetic resonance imaging (LGE‐MRI), respectively. Results The mean SUV max at the PV antrum was significantly higher than that on the healthy LA wall (2.12 ± 0.35 vs 1.73 ± 0.30, P = .00021). The volume of the atrial inflammation strongly correlated with that of the atrial fibrosis (r = .94 [.76‐.99], P = .00006). Conclusions The atrial inflammation after CBA could be detected by PET/MRI. CBA‐induced atrial inflammation was strongly associated with consequent lesion maturation., Atrial inflammation plays an important role in initiating atrial fibrosis, which could perpetuate atrial fibrillation (AF).This study demonstrated the feasibility of the PET/MRI visualizing inflammation in the left atrium.
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- 2020
45. Gut microbial composition in patients with atrial fibrillation: effects of diet and drugs
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Ken-ichi Hirata, Yoshihiro Saito, Tokiko Tabata, Koji Hosomi, Motohiko Miyachi, Kenji Mizuguchi, Jun Kunisawa, Tomohiro Hayashi, Hitoshi Kawashima, Haruka Murakami, Jonguk Park, Naofumi Yoshida, Tomoya Yamashita, Kana Konishi, and Koji Fukuzawa
- Subjects
DNA, Bacterial ,Male ,Physiology ,Gut microbiota ,030204 cardiovascular system & hematology ,Gut flora ,medicine.disease_cause ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Alistipes ,Stroke ,030304 developmental biology ,Aged ,Retrospective Studies ,chemistry.chemical_classification ,0303 health sciences ,biology ,Streptococcus ,business.industry ,Dietary habits ,Atrial fibrillation ,medicine.disease ,biology.organism_classification ,n-3 polyunsaturated fatty acids ,Diet ,Gastrointestinal Microbiome ,chemistry ,Heart failure ,Quality of Life ,Dysbiosis ,Original Article ,Eicosadienoic acid ,Female ,Cardiology and Cardiovascular Medicine ,business ,Polyunsaturated fatty acid - Abstract
Atrial fibrillation (AF) reduces the quality of life by triggering stroke and heart failure. The association between AF onset and gut metabolites suggests a causal relationship between AF and gut microbiota dysbiosis; however, the relationship remains poorly understood. We prospectively enrolled 34 hospitalized patients with AF and 66 age-, sex-, and comorbidity-matched control subjects without a history of AF. Gut microbial compositions were evaluated by amplicon sequencing targeting the 16S ribosomal RNA gene. We assessed differences in dietary habits by using a brief-type self-administered diet history questionnaire (BDHQ). Gut microbial richness was lower in AF patients, although the diversity of gut microbiota did not differ between the two groups. At the genus level,Enterobacterwas depleted, whileParabacteroides,Lachnoclostridium,Streptococcus,andAlistipeswere enriched in AF patients compared to control subjects. The BDHQ revealed that the intake of n-3 polyunsaturated fatty acids and eicosadienoic acid was higher in AF patients. Our results suggested that AF patients had altered gut microbial composition in connection with dietary habits.
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- 2020
46. Cardiac resynchronization therapy improves left atrial reservoir function through resynchronization of the left atrium in patients with heart failure with reduced ejection fraction
- Author
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Koji Fukuzawa, Hidekazu Tanaka, Kumiko Dokuni, Kensuke Matsumoto, Ken-ichi Hirata, Kazuhiro Tatsumi, and Makiko Suto
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Cardiac resynchronization therapy ,030204 cardiovascular system & hematology ,Ventricular Function, Left ,Left atrial reservoir function ,03 medical and health sciences ,0302 clinical medicine ,Left atrial ,Predictive Value of Tests ,Internal medicine ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,cardiovascular diseases ,030212 general & internal medicine ,Ventricular dyssynchrony ,Lead (electronics) ,Cardiac imaging ,Aged ,Retrospective Studies ,Aged, 80 and over ,Echocardiography, Doppler, Pulsed ,Heart Failure ,Ejection fraction ,business.industry ,Speckle-tracking strain analysis ,Stroke Volume ,Recovery of Function ,Middle Aged ,medicine.disease ,Progression-Free Survival ,Heart failure ,cardiovascular system ,Cardiology ,Atrial Function, Left ,Female ,Left atrial dyssynchrony ,Cardiology and Cardiovascular Medicine ,business - Abstract
This study aimed to test the hypothesis that left ventricular dyssynchrony may negatively affect left atrial (LA) dyssynchrony and reservoir function, and cardiac resynchronization therapy (CRT) may improve LA function. It also assessed, whether residual LA dyssynchrony affects the prognosis in patients with heart failure with reduced ejection fraction (HFrEF). Ninety subjects were included: 40 HFrEF patients with a wide-QRS complex (≧130 ms), 28 HFrEF patients with a narrow-QRS, and 22 normal controls. LA global longitudinal strain (LA-GLS) and LA dyssynchrony were quantified by speckle-tracking strain analysis. LA dyssynchrony was defined as the maximal difference of time-to-peak strain (LA time-diff). All patients with a wide-QRS underwent CRT, and event-free survival was tracked for 24 months. At baseline, LA dyssynchrony was significantly more pronounced in patients with a wide-QRS HFrEF (342 ± 126 ms) than that in patients with a narrow-QRS (236 ± 127 ms, P < 0.001) and controls (186 ± 78 ms, P < 0.001). Six months after CRT, LA-GLS significantly improved from 11.9 ± 4.7 to 19.6 ± 10.1% (P < 0.05) and LA time-diff was reduced from 338 ± 123 to 245 ± 141 ms (P < 0.05) in responders only. Patients with an LA time-diff < 202 ms and those with an LA-GLS ≧14.6% six months after CRT showed significantly better outcomes than the others (P < 0.05, respectively). Among the responders, those with an LA time-diff < 202 ms after CRT showed a better prognosis than others (P < 0.05). CRT improved LA dyssynchrony and reservoir function through the improved left ventricular coordination. Reduced LA dyssynchrony and improved LA reservoir function after CRT lead to better outcomes.
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- 2020
47. Circulating intermediate monocytes and toll-like receptor 4 correlate with low-voltage zones in atrial fibrillation
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Tokiko Tabata, Tomoya Yamashita, Jun Sakai, Atsusuke Yatomi, Makoto Takemoto, Hideya Suehiro, Yusuke Sonoda, Atsushi Suzuki, Toshihiro Nakamura, Koji Fukuzawa, Tomomi Akita, Kyoko Yamamoto, Ken-ichi Hirata, Mitsuru Takami, Kazutake Nakasone, Naofumi Yoshida, Hiroyuki Takahara, and Kunihiko Kiuchi
- Subjects
Male ,medicine.medical_specialty ,CD14 ,Lipopolysaccharide Receptors ,Action Potentials ,Inflammation ,030204 cardiovascular system & hematology ,CD16 ,GPI-Linked Proteins ,Monocytes ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,Heart Rate ,Internal medicine ,Atrial Fibrillation ,Humans ,Medicine ,Prospective Studies ,030212 general & internal medicine ,Receptor ,Aged ,Toll-like receptor ,business.industry ,Receptors, IgG ,Atrial fibrillation ,Middle Aged ,medicine.disease ,Toll-Like Receptor 4 ,Endocrinology ,TLR4 ,Female ,Inflammation Mediators ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Biomarkers - Abstract
Inflammation has been suggested to play a key role in the pathogenesis of atrial fibrillation (AF). Our hypothesis was that this inflammation, mediated by intermediate monocytes and toll-like receptor 4 (TLR4), causes the formation and expansion of low-voltage zones (LVZs). Prior to ablation, the monocyte subsets of 78 AF patients and TLR4 expression of 66 AF patients were analyzed via a flow cytometric analysis. Based on the CD14/CD16 expression, the monocytes were divided into three subsets: classical, intermediate, and non-classical. At the beginning of the ablation session, voltage mapping was performed. LVZs were defined as all bipolar electrogram amplitudes of
- Published
- 2020
48. Revisiting the prevalence and diversity of localized thinning of the left ventricular apex
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Ken-ichi Hirata, Takayoshi Toba, Shumpei Mori, Hidekazu Tanaka, Koji Fukuzawa, Koji Miyamoto, Yu Izawa, Atsushi K. Kono, and Kyoko Yamamoto
- Subjects
Adult ,Male ,Heart Diseases ,Cardiac computed tomography ,Heart Ventricles ,medicine.medical_treatment ,Computed tomography ,030204 cardiovascular system & hematology ,Left ventricular hypertrophy ,Severity of Illness Index ,Ventricular Function, Left ,Left ventricular apex ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Physiology (medical) ,medicine ,Computed tomography scanner ,Humans ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Aged, 80 and over ,Ventricular Remodeling ,medicine.diagnostic_test ,business.industry ,Aortic Valve Stenosis ,Middle Aged ,Multiplanar reconstruction ,Ablation ,medicine.disease ,Stenosis ,cardiovascular system ,Radiographic Image Interpretation, Computer-Assisted ,Female ,sense organs ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,Nuclear medicine ,business - Abstract
Background The left ventricular apex commonly has a paper-thin structure. However, available data about its structure are limited to variable samples, methodologies, and results. Objective To investigate the structural anatomy of the left ventricular apex using living heart datasets with the latest computed tomography scanner. Methods One hundred thirty-one consecutive patients (median age, 73 years; 58% men) who underwent cardiac computed tomography were retrospectively analyzed. Patients with severe aortic stenosis were analyzed separately. Thickness and diameters of the thinnest part of the left ventricular apex during mid-diastole were measured using orthogonal multiplanar reconstruction images. The area of thinning was estimated using the formula for the ellipse. Results In 88 patients without severe aortic stenosis, the median thickness of the thinnest area of the left ventricular apex was only 0.9 mm. Among them, 74%, 99%, and 100% of cases displayed a left ventricular apex thinner than 1.0, 3.0, and 5.0 mm, respectively. The median area of the thinnest region was 5.6 mm2 . In 43 patients with severe aortic stenosis, the median thickness of the thinnest area of the left ventricular apex was 1.2 mm. Among them, 51%, 93%, and 100% of cases displayed a left ventricular apex thinner than 1.0, 3.0, and 5.0 mm, respectively. The median area of the thinnest region was 3.9 mm2 . Conclusions Localized thinning of the left ventricular apex is unexceptional, regardless of aortic stenosis with concentric left ventricular hypertrophy, thus highlighting the need for a reappreciation of this feature to avoid inadvertent catastrophic complications.
- Published
- 2020
49. Predictors of VT recurrence in patients with VT inducibility at the end of radiofrequency ablation: Should we use VT non-inducibility as a routine endpoint?
- Author
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Kazutaka Nakasone, Koji Fukuzawa, Kunihiko Kiuchi, Mitsuru Takami, jun sakai, Toshihiro Nakamura, atsusuke yatomi, Yusuke Sonoda, Hiroyuki Takahara, Kyoko Yamamoto, Yuya Suzuki, Kenichi Tani, Hidehiro Iwai, Yusuke Nakanishi, and Ken-ichi Hirata
- Abstract
Introduction: It has been reported that ventricular tachycardia (VT) non-inducibility at the end of ablation is associated with less likely VT recurrence. However, it is not clear whether we should use VT non-inducibility as routine end point in VT ablation. The aim of this study was to evaluate VT recurrence in patients in whom VT non-inducibility could not be achieved at the end of the RF ablation and the factors attributing to the VT recurrence. METHODS and RESULTS: We analyzed 84 consecutive patients that underwent RF ablation, and 64 patients in whom VT non-inducibility could not be achieved were studied. The primary endpoint was recurrence of any sustained VT during the follow-up. During a median follow-up period of 1.4 years (IQR:0.3-2.0), 22 (34%) of the cases had VT recurrences. In the multivariate analysis showed that an LVEF≥35% (HR:0.21; 95% CI:0.07- 0.54; P
- Published
- 2021
50. Treatment Strategy for Fatal Arrhythmias in Ebstein’s Anomaly Combined With Leadless Pacemaker and S-ICD Implantations
- Author
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Mitsuru Takami, Koji Fukuzawa, Kunihiko Kiuchi, Kensuke Matsumoto, Yu Izawa, and Ken-ichi Hirata
- Subjects
S-ICD ,catheter ablation ,Ebstein’s anomaly ,ventricular tachycardia ,Cardiology and Cardiovascular Medicine ,leadless pacemaker ,cardiac surgery - Abstract
The management of heart rhythm disorders in patients with adult congenital heart disease and limited vascular access is challenging. We present the case of a 38-year-old woman with Ebstein’s anomaly who underwent implantation of a combination of a leadless pacemaker and a subcutaneous implantable cardioverter-defibrillator to manage fatal arrhythmias. (Level of Difficulty: Intermediate.)
- Published
- 2022
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