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Objective: Coronavirus disease 2019 (COVID-19) was associated with a higher risk of arrhythmia in infected patients. However, there are no reports about the effect of the ongoing pandemic on arrhythmias in the non-infected population. We measured the arrhythmia burden in a non-infected population with cardiac implantable devices. Methods: The arrhythmia burden during the COVID-19 pandemic was compared to a 6-month interval in the pre-COVID-19 period. The COVID-19 pandemic was divided into high-risk (17 January 2020 to 16 March 2020) and low-risk periods (17 March 2020 to 17 July 2020) according to whether there were locally infected patients. Arrhythmia burdens were compared among the pre-COVID-19, high-risk, and low-risk periods. Results: A total of 219 patients with 1859 episodes were included. We observed a larger proportion of patients with atrial fibrillation (AF) during the COVID-19 pandemic (38.36% vs 26.03%, p = 0.006). There was not significantly more ventricular arrhythmia during the COVID period than the pre-COVID-19 period (p > 0.05). During the high-risk period, daily frequency of non-sustained ventricular tachycardia (NSVT) (0.0172, 0.0475 vs 0.0109, 0.0164, p < 0.05), atrial tachycardia (AT) (0.0345, 0.0518 vs 0.0164, 0.0219 p < 0.05) and AF (0.0345, 0.0432 vs 0.0164, 0.0186, p < 0.05) and daily duration of NSVT (0.1982, 0.2845 vs 0.0538, 0.1640 p < 0.05) were higher and longer than those in the pre-COVID-19 period. Regression modeling showed that the impact of COVID-19 pandemic lead to an increased onset of AF (odds ratio 2.465; p < 0.01). Patients with paroxysmal AF who had undergone a previous radiofrequency ablation had a lower burden of AF (incidence 21.43% vs 55.00%, P = 0.049, daily frequency 0.0000, 0.0027 vs 0.0000, 241.7978, P = 0.020) during the pandemic. Conclusion: The COVID-19 pandemic contributed to a higher burden of arrhythmias in non-infected patients. Patients would experience a lower burden of AF following radiofrequency ablation treatment, and this effect persisted during the pandemic.

Background: Patients with anaplastic thyroid cancer (ATC) have poor overall survival, and the optimal management approach remains unclear. The aim of this study is to evaluate our experience with multimodality (MMT) versus limited treatment (LT) for ATC.Patients and Methods: A cohort study of patients with ATC managed in a tertiary referral center was undertaken. The outcomes of MMT were compared with those of LT. The primary outcome measures were locoregional control and progression-free and overall survival. Secondary outcome measures were treatment-related complications and factors associated with improved survival.Results: In total, 59 patients (35 females) with a median age of 73 years (range 39-99 years) and ATC stage IVA (n = 2), IVB (n = 28), or IVC (n = 29) were included. LT was utilized in 25 patients (42%), and 34 cases had MMT. MMT patients had a longer time of locoregional control (18.5 versus 1.9 months; p < 0.001), progression-free survival (3.5 versus 1.2 months; p < 0.001), and overall survival (6.9 versus 2.0 months; p < 0.001) when compared with LT. For patients with stage IVC ATC, locoregional control (p = 0.03), progression-free survival (p < 0.001), and overall survival (p < 0.001) were superior in the MMT cohort compared with LT. MMT had more treatment-related complications than LT (p < 0.001). An Eastern Cooperative Oncology Group performance status < 2 (HR 0.30; p = 0.001) and MMT (HR 0.35; p = 0.008) were associated with improved overall survival.Conclusion: MMT is likely to improve locoregional control, progression-free survival, and overall survival in selected ATC patients including stage IVC tumors but comes with a greater complication risk.

Background Postoperative follow-up of papillary thyroid cancer includes serial serum thyroglobulin levels. This study aimed to determine whether stimulated thyroglobulin levels measured in the early postoperative period can accurately quantify the risk of recurrence in papillary thyroid cancer. Methods We undertook a cohort study of patients who underwent total thyroidectomy for papillary thyroid cancer ≥ 10 mm in the period 2000 to 2016 with complete biochemical data. All patients had a postoperative stimulated thyroglobulin measured within 3 months after total thyroidectomy. Structural recurrence was defined as disease detected on imaging and confirmed on histology. Biochemical disease was defined as patients with stimulated serum thyroglobulin ≥ 1 ng/mL with no evidence of structural disease. Results This study included 502 patients with a mean age of 50 years and median tumor diameter of 20 mm. Median follow-up was 18 months. Stimulated postoperative thyroglobulin was measured before radioiodine-ablation and was categorized into 3 groups: (1) 219 (44%) patients had thyroglobulin 1 ng/mL; (2) 55 (11%) had 1ng/mL ≤ thyroglobulin 2 ng/mL; and (3) 228 (45%) had thyroglobulin ≥ 2 ng/mL. The structural recurrence rate for each group was 5%, 2%, and 30%, respectively (P Conclusion In patients undergoing total thyroidectomy for papillary thyroid cancer, early postoperative stimulated thyroglobulin accurately quantifies the risk of structural disease recurrence.

Background Ventricular arrhythmias (VAs) arising from the origin above pulmonary valve lack comprehensive investigation. This study aimed to disclose the characteristics and radiofrequency catheter ablation (RFCA) outcomes for those VAs. Methods One hundred six VAs arising from the region above pulmonary valve treated with RFCA were included in this study. Results Seventy-five cases were identified in the pulmonary sinus cusps (PSCs, 32 in left sinus cusp (PLC), 15 in right (PRC), 28 in anterior (PAC)) and 31 cases were in the main stem of pulmonary artery (MSPA, 18 above PLC (LMSPA), 3 above PRC (RMSPA), 10 above PAC (AMSPA)). Compared with PSCs VAs, MSPA VAs exhibited a higher R wave amplitude in the inferior leads, a total inferior R amplitude > 5.1 mV predicting MSPA origins. LMSPA, RMSPA and AMSPA VAs resembled PLC, PRC and PAC VAs in electrocardiographic characteristics respectively. No electrophysiological differences were found between PSCs and MSPA VAs. The irrigated-up catheter and R0 Swartz long sheath were more utilized for ablation of PSCs VAs than for MSPA VAs. All these VAs were successfully eliminated by RFCA. Conclusion VAs arising from the origin above pulmonary valve were common. Based on certain electrocardiographic characteristics, they could be roughly located, which contributed to an effective RFCA.

Background: The worldwide incidence of papillary thyroid carcinoma (PTC) has increased. Efforts to reduce overtreatment follow two approaches: limiting diagnostic workup of low-risk thyroid nodules and pursuing active surveillance (AS) after diagnosis of microscopic PTC (mPTC). However, most studies on AS have been performed in countries with a relatively high proportion of overdiagnosis and thus incidental mPTC. The role of AS in a population with a restrictive diagnostic workup protocol for imaging and fine-needle aspiration remains unknown. Therefore, the aim of this study was to describe the proportion and characteristics of patients with mPTC in the Netherlands and to describe the potential candidates for AS in a situation with restrictive diagnostic protocols since 2007.Methods: All operated patients with an mPTC in the Netherlands between 2005 and 2015 were identified from the Netherlands Cancer Registry database. Three groups were defined: (Group 1) mPTC with preoperative distant or lymph node metastases, (Group 2) mPTC in pathology report after thyroid surgery for another indication, and (Group 3) patients with a preoperative high suspicious thyroid nodule or proven mPTC (Bethesda 5 or 6). Only patients in Group 3 were considered potential candidates for AS.Results: A total of 1018 mPTC patients were identified. Group 1 consisted of 152 patients with preoperatively discovered metastases. Group 2 consisted of 667 patients, of whom 16 (2.4%) had lymph node metastases. There were 199 patients in Group 3, of whom 27 (13.6%) had lymph node metastases. After initial treatment in Group 3, 3.5% (7/199) of the patients had recurrence.Conclusions: Restrictive diagnostic workup strategies of patients with small thyroid nodules lead to limited patients eligible for AS and a higher incidence of lymph node metastases. We believe that there is limited additive value for AS in countries with restrictive diagnostic workup guidelines such as in the Netherlands. However, if an mPTC is encountered, AS can be offered on an individual basis.

Background Ventricular arrhythmias (VAs) originating from the left ventricular summit is a challenge for radiofrequency catheter ablation (RFCA). The present study aimed to investigate the appropriate RFCA strategy for VAs originating from the left ventricular summit. Methods Forty-five consecutive patients with VAs arising from the left ventricular summit were successfully ablated at our cardiac electrophysiology center and reviewed in the study. Results Thirty-two cases of VAs were eliminated in the left ventricular endocardium by retrograde transaortic (n = 22, 22/45, 48.9%) or antegrade transseptal (n = 10, 10/45, 22.2%) approaches, the other 13 cases were eliminated in the left ventricular epicardium by distal great cardiac vein (DGCV) approach (n = 13, 13/45, 28.9%). Though these VAs were similar in electrocardiographic (ECG) morphology, the pseudo delta waves (PDW), intrinsicoid deflection time (IDT), maximal deflection index (MDI) differed among them, PDW >53 ms, IDT > 74 ms, MDI > 0.45 strongly indicated that ablating left ventricular summit VAs by DGCV approach. During mean follow-up of 19.5 ± 13.2 (range, 3-60) months, 2 (4.4%) patients experienced VAs recurrence. Conclusion This retrospective study showed that VAs of left ventricular summit origin can be effectively cured with RFCA. For these VAs, prolonged PdW, IDT, MDI indicating RFCA by DGCV approach can be attempted firstly.

Background---Persistent myocardial ischemia occurred in post-myocardial infarction could lead to fatal ventricular arrhythmias like ventricular tachycardia and fibrillation and also has high rate of mortality. Dexmedetomidine (Dex), a highly selective α2-agonist, applied for daily anesthetic practice prevalently, was associated with a decrease in postoperative mortality and decreased incidence of postoperative complications and delirium in patients under cardiac surgery. Present study investigated the effects of dexmedetomidine on arrhythmogenic properties following ischemic cardiomyopathy (ICM) after post-myocardial infarction. Methods and results---48 rats developing ischemic cardiomyopathy after persistent ligation of left anterior descending artery for 4 weeks were divided into 6 groups randomly: Sham (n=8), Sham+BML (n=8), ICM (n=8), ICM+BML (n=8), ICM+Dex (n=8), ICM+Dex+BML (n=8). Treatments were started after the ischemic cardiomyopathy was confirmed (the day after echocardiographic measurement) in rats and continued for 4 weeks (inject intraperitoneally, daily). Dexmedetomidine treatment restrained the production of collagens, cytokines, and other inflammatory mediators in rats with ischemic cardiomyopathy via suppressing NF-κB activation, and increased the distribution of connexin 43 (Cx43) through eliciting phosphorylation of adenosine 5‘-monophosphate-activated protein kinase (AMPK). Additionally, dexmedetomidine reduced the occurrence of ventricular arrhythmia (ventricular premature beat or ventricular tachycardia) and decreased inducibility quotient of ventricular arrhythmias by PES as well as improving cardiac contraction partly. BML-275 dihydrochloride (BML), the AMPK antagonist, weakened the cardio-protective effect of dexmedetomidine, demonstrated as inhibiting the anti-inflammatory and anti-arrhythmic effects of dexmedetomidine. Conclusion---Dexmedetomidine conferred anti-arrhythmia effects in ischemic cardiomyopathy after post-myocardial infarction through regulation of connexin 43 and suppression of fibrosis and inflammation. Eliciting of phosphorylation of adenosine 5’-monophosphate-activated protein kinase and suppressing of NF-κB activation subsequently might contribute to the anti-arrhythmic and anti-inflammatory properties of dexmedetomidine.

Aims To investigate the characteristics of bipolar intracardiac electrograms (bi-EGMs) in target sites of ventricular arrhythmias (VAs) originating from different regions of ventricular outflow tract (VOT). Methods and results Two hundred and seventy patients undergoing first-time ablation for VAs originated from distal great cardiac vein (DGCV), aortic sinus cusps (ASCs), or pulmonary sinus cusps (PSCs) were enrolled in present study. Local intracardiac bipolar recordings on 243 successful sites and 506 attempted but unsuccessful ablation sites were analysed. Specific potentials in bi-EGMs on successful sites were more common compared with unsuccessful sites (76.95%, 187/243 vs. 25.49%, 129/506, P Conclusion Distinctive morphology of bi-EGMs during VAs can be found in different regions of VOT, which probably due to changes in the arrangements of myocardial sleeves. Correct identification and better understanding of the distinctive features of these bi-EGMs with regards to the anatomic location was important, the presence of specific potentials may add help in successful ablation.

Background Idiopathic ventricular arrhythmias (IVAs) can originate from the distal great cardiac vein (DGCV). However, inadequate distinction sometimes occurs when electrocardiographic (ECG) characteristics are used to distinguish ventricular arrhythmias (VAs) arising from the DGCV from those arising from the adjacent left ventricular endocardium (LV ENDO). Objective The purpose of this study was to identify distinct ECG features in patients with idiopathic IVAs originating from the DGCV. Methods A total of 32 patients with IVAs originating from the DGCV were identified from a consecutive group of 874 patients undergoing IVAs ablation. Patients with IVAs from the DGCV were compared with a consecutively chosen series of 40 patients with IVAs in whom the site of origin was the adjacent LV ENDO. Results Of the 32 patients with IVAs arising from the DGCV, 13 had distinct ECG characteristics compared with the LV ENDO group. Notches in both the upstroke and downstroke of the R wave in lead III were found in all 13 patients. However, the characteristic ECG pattern in lead III was found in 1 of 40 patients in the LV ENDO group. The ECG characteristic of both early notch and late notches in lead III has sensitivity of 40.6%, specificity of 97.5%, negative predictive value of 67.2%, and positive predictive value of 92.9% to predict VAs arising from the DGCV. Conclusion The distinct ECG characteristics of VAs originating from the DGCV can help differentiate from adjacent LV ENDO sites of origin.

AIMs Age-related structure changes and dysfunction of heart are likely to contribute heart failure in elderly people. Recent studies have shown that folic acid supplementation effectively delays age-related declines; nevertheless, the role and mechanism of folic acid in protection against cardiac aging remain unclear. The aim of the current study was to determine whether folic acid inhibits remodeling and dysfunction during the aging process and to elucidate its underlying mechanisms. Main methods Male C57BL/6 mice aged 4 months (adult) and 14 months (aged) were fed a standard diet or a folic acid diet for 6 months. Echocardiograms and histological evaluations were used to detect left ventricle (LV) function, LV remodeling, cardiac fibrosis, apoptosis and oxidative stress. Senescence-associated β-galactosidase activity staining was used to detect cardiac senescence rate. Western blotting was employed to detect the levels of senescence and ER stress signaling. Key finding LV hypertrophy was reduced and LV function was preserved in aged mice that consumed folic acid. LV remodeling, fibrosis, apoptosis and oxidative stress were also reduced in mice that consumed folic acid. Senescence-associated β-galactosidase activity staining revealed that folic acid attenuated cardiac senescence by down-regulating p53/p21/p16 levels. Protein assays of myocardial tissue revealed that the ER stress pathway is the important underlying mechanism during cardiac senescence. The involvement of these pathways was confirmed by doxorubicin-induced H9C2 cardiomyocyte senescence. Significance These findings suggest that folic acid prevents age-related cardiac remodeling and dysfunction and attenuates cellular senescence. ER stress responses may be the mechanisms involved in the protective effect of folic acid against cardiac aging.

With the chronic ischemia persisting after acute myocardial infarction, the accompanying low-degree inflammation and subsequent fibrosis result in progression of cardiac remodeling and heart failure. Recently, Sodium Houttuyfonate (SH), a pure compound extracted from Houttuynia cordata, has been confirmed exerting anti-inflammatory and anti-fibrotic effects under diseased situations. Here, we aimed to investigate whether SH could reverse the cardiac remodeling post-myocardial infarction by alleviating cardiac inflammation and fibrosis. Left anterior descending coronary artery of adult male Sprague-Dawley rats was ligated to elicit myocardial infarction. Low and high dose of SH was administered by oral gavage for four consecutive weeks post-myocardial infarction. Long-term SH treatment decreased heart rate, heart weight/ body weight (HW/BW), and left ventricle weight/body weight (LVW/BW), reduced cardiac expression of brain natriuretic peptide (BNP), improved left ventricular heart function, and ameliorated the histopathological changes caused by myocardial infarction. Western blotting revealed the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), transforming growth factor-β (TGF-β), collagen I, and collagen III of the infarcted ventricle were reduced by SH treatment. Meanwhile, we found that SH treatment post-myocardial infarction activated AMP-activated protein kinase (AMPK) and suppressed nuclear factor-κB p65 (NF-κB p65). Furthermore, on H9C2 cells induced hypoxic injury with cobalt chloride (CoCl2), the reduction of inflammatory cytokines (IL-6, TNF-α, and TGF-β), activation of AMPK, and suppression of NF-κB p65 were also observed by SH treatment. However, transfection of H9C2 with AMPKα siRNA blunted the suppression of NF-κB p65 and inflammatory cytokines (IL-6, TNF-α, and TGF-β) by SH post-hypoxia. Taken together, these findings suggested that long-term administration of SH post-myocardial infarction reduced cardiac inflammatory and fibrotic responses, and reversed cardiac remodeling process. The underlying mechanism may be activating AMPK and suppressing NF-κB pathway.

Background Patients with frequent premature ventricular contractions (PVCs) are often symptomatic. Catheter ablation was usually indicated to eliminate symptoms in patients with PVCs-induced cardiomyopathy. Currently, PVCs-ablation is also applied for patients with PVCs and no structural heart diseases (SHD); however, the safety and efficacy of ablation in these patients remains unclear. Methods In this retrospective study, data from patients who underwent ablation for PVCs from January 2010 to December 2016 at our hospital was retrieved. Predictors of complications and acute procedural success were evaluated. Results A total of 1231 patients (mean age 47.8 ± 16.8 years, 59% female) were included. The overall complication rate was 2.7%, and the most common complication was hydropericardium. Two ablation-related mortalities occurred. One patient died of coronary artery injury during the procedure and the other died from infectious endocarditis. Location (left ventricle and epicardium) was the main predictor of complications, with right ventricular outflow tract (RVOT) predicting fewer complications. The acute procedural success rate was 94.1% in all patients. The main predictor of acute procedural success was RVOT origin, while an epicardial origin was a predictor of procedural failure. Conclusion Locations of left ventricle and epicardium were predictors of procedural complications for patients with PVCs. Therefore, ablation is not recommended in these patients. For other origins of PVCs, particularly RVOT origin, ablation is a safety and effective treatment.

Catheter Ablation of Idiopathic Epicardial Ventricular Arrhythmias. Idiopathic epicardial ventricular arrhythmias (IEVAs) originating from the vicinity of the coronary sinus system are not uncommon, accounting for about 9% of idiopathic ventricular arrhythmia cases. IEVAs share clinical presentation and electrophysiological characteristics with ventricular arrhythmias arising from the right ventricular outflow tract possibly as manifestations of cAMP-mediated triggered activity and delayed after-depolarizations. Detailed analysis of standard 12-lead electrocardiogram morphology by using unique variables and algorithms allows clinicians to predict probable location of epicardial foci and informs optimal catheter ablation strategy. Epicardial mapping and ablation through the coronary sinus and its branches is effective and safe, and increasingly favored. However, it is important because of the common perivascular origin of IEVAs to perform coronary angiography prior to or after ablation and to select the appropriate ablation energy form to avoid serious complications.

Background In patients with triple valve replacement developing third-degree atrioventricular block (AVB), the most appropriate approach for permanent pacemaker implantation remains questionable. Case presentation In this case presentation, we first described the approach of implantation of the cardiac resynchronization therapy pacemaker (CRT-P) via one bipolar pacing lead in middle cardiac vein (MCV) and one quadripolar pacing lead in anterior interventricular vein (AIV) in a patient developing complete AVB, who had been previously diagnosed with rheumatic valvular heart disease with triple valve replaced. After the CRT-P implantation, the two pacing leads in coronary sinus (CS) provided a dual-site ventricular pacing from the anterior septum and posterior septum, which resulted in a narrow QRS complex and an increased ventricular synchrony. During the long-term follow-up, no deterioration of heart function was documented and pacing parameters remained good. Conclusion In this patient developing complete AVB with triple valve replaced, our approach of CRT-P implantation provides an effective and reliable ventricular pacing, and is an alternative option when transvenous right ventricular pacing, transseptal left ventricular pacing and transpericardial epicardium pacing are not possible. Further prospective randomized trials are required to confirm the efficiency of our approach of dual-site ventricular pacing by CRT-P in this kind patients.

Objective To investigate electrocardiographic (ECG) characteristics and radiofrequency catheter ablation (RFCA) efficacy for premature ventricular complexes (PVCs) and idiopathic ventricular tachycardias (IVTs) originating from ventricular septum areas adjacent to atrioventricular annulus (VS-AVA). Methods Among 1,505 consecutive PVCs/IVTs cases, 106 (7.04%) were confirmed as origin of VS-AVA guided by both fluoroscopy and three-dimensional mapping system during RFCA. Characteristics of surface 12-lead ECG were analyzed. Results The overall success rate for RFCA of PVCs/IVTs originating from VS-AVA was 82.08% (87/106), common ECG characteristics were: mainly positive R wave on lead I; dominant-positive R on aVL (91/106, 85.85%) for most, r (1/106, 0.94%) or qr (14/106, 13.21%) in few; QS or qs on aVR; and decreasing R wave amplitude and increasing S wave depth on II, III, and aVF from superior to inferior septum; and S wave on at least one inferior lead (generally III). Distinctive ECG features were: precordial transition zone before or after V2 for septum adjacent to mitral (MA, 19/19, 100.0%) or tricuspid (TA, 74/87,85.05%) annulus origin; initial r wave and rS on V1 for superior septum near TA (above His bundle) origin (9/10, 90.0%) with no initial r wave for most other origins; and QS on V1 for mid-inferior septum near TA origin (73/77, 94.81%) and QR (Qr, qR or qr) on V1 for septum near MA origin (17/19, 89.47%). Conclusion Distinctive ECG characteristics of PVCs/IVTs originating from VS-AVA aid in origin localization guiding effective RFCA.

Asymmetric dimethylarginine (ADMA), an inhibitor of nitric oxide synthase, is a novel risk factor of cardiovascular disease. Endothelial progenitor cells (EPCs) bear typical endothelial characteristics and are thought to contribute to neovascularization by providing new endothelial cells (ECs) after arterial injury. Many studies have shown that ADMA can induce EPC apoptosis and dysfunction, but the underlying mechanism is not well understood. EPCs from umbilical cord blood were cultured in EGM-2 medium with particular growth factors and supplemented with 10% fetal bovine serum. The cells were treated with different concentrations of ADMA (5, 10, and 50 μmol/L). Endoplasmic reticulum (ER) stress marker levels were examined by western blot analysis. After 24-hour incubation, ADMA induced apoptosis of EPCs and significantly decreased the proliferation, migration, and vasculogenesis capacity of EPCs. We also found that ADMA treatment activated phosphorylated protein kinase RNA-activated-like ER kinase (PERK), a stress sensor protein in the endoplasmic reticulum (ER). The activated PERK induced 78 kDa glucose-regulated protein (GRP-78) and C/EBP homologous protein (CHOP) expression. Additionally, the inhibition of the ER stress pathway by Salubrinal (a specific ER stress inhibitor) can attenuate ADMA-induced apoptosis of EPCs. Overall, these observations indicate that ADMA may induce the apoptosis and dysfunction of EPCs through the ER stress pathway.

Background Ventricular outflow tract(VOT) ventricular arrhythmias(VAs) presenting qrS pattern or QS pattern with a notch on the descending limb in lead V1 were consistently thought of arising from the commissure between left and right coronary cusp (L-RCC) by previous studies. However, we found they could originate from other anatomic structures in VOT. This study aimed to investigate the exact origin of this kind VAs. Methods Forty-nine patients of VOT premature ventricular contrations/ventricular tachycardia(PVCs/VT) with lead V1 presenting qrS pattern or QS pattern with a notch on the descending limb undergoing successful radiofrequency catheter ablation(RFCA) in our center were analyzed. Results 12-lead electrocardiogram(ECG) of these PVCs/VT were summarized. Among these PVCs/VT, 37 cases exhibited qrS morphology in lead V1, 12 cases presented QS pattern with a notch on the descending limb in the same lead. Based on the successful ablation sites, these PVCs/VT were divided into 2 groups: (1)Right ventricular outflow tract(RVOT) group (26 cases), and (2) Left ventricular outflow tract (LVOT) group(23 cases, 4 cases originating from the left coronary cusp(LCC), 2 from the right coronary cusp(RCC), 16 from the L-RCC, 1 from the area inferior to LCC(ILCC)). The ECG characteristics of each PVCs/VT were analyzed. Among these PVCs/VT, applying the precordial transitional zone index(TZ index)

Prominent T-wave inversions are well recognized electrocardiographic signs that can occur in acute myocardial infarction (AMI). However, the giant negative T waves may be associated with myocardial stunning without AMI. This case report describes 2 patients without AMI who developed rare giant T-wave inversions measuring up to 35 mm in depth and QT prolongation after admission to hospital. While 1 patient presented with acute pulmonary edema, the other patient presented with severe chest pain at rest and transient ST elevation. The giant T-wave inversion with QT prolongation may be caused by myocardial stunning due to the triple vessel diseases and elevated wall stress, high-end diastolic pressure and decreased coronary arterial flow during pulmonary edema in the first patient. The giant T-wave inversion with QT prolongation in the second patient may be caused by myocardial stunning due to the left anterior descending artery spasm (transient ST elevation) leading to transient total occlusion of left anterior descending artery. Percutaneous coronary intervention was successfully undergone for both patients. The patients remained well. The electrophysiologic mechanism responsible for giant T-wave inversion with QT prolongation is presently unknown. The two cases demonstrate that the rare giant negative T waves may be associated with myocardial stunning without AMI.

We report a case of atrioventricular nodal reentrant tachycardia (AVNRT) coexistent with His bundle anomaly and atrial septal defects. The His-bundle potential was recorded at the coronary sinus (CS) ostium. Fractionated atrial potentials and an A:V electrogram ratio 1:3 were recorded at the anterior septum of the tricuspid annulus approximately 2 cm from CS ostium. Radiofrequency catheter ablation at the anterior septum of the tricuspid annulus effectively eliminated AVNRT.

Objectives This study aimed to investigate electrocardiographic characteristics and effects of radiofrequency catheter ablation (RFCA) for patients with symptomatic premature ventricular complexes (PVCs) and idiopathic ventricular tachycardias (IVTs), originating from the different portions of the left coronary veins. Background Inadequate distinction was made in the past for the PVC/IVTs located in the different portions of the left coronary veins, especially the distal great cardiac vein (DGCV) and the proximal portion of the anterior interventricular vein (PAIV) and the extended tributary of DGCV located distal to the origin of AIV (EDGCV). Methods Characteristics of body surface electrocardiogram (ECG) and electrophysiologic recordings were analyzed in 12 patients with symptomatic PVCs/IVTs originating from the vicinity of the left coronary veins. Results Among 490 patients with PVCs/IVTs, the incidence of ventricular arrhythmias originating from the left ventricular epicardium adjacent to the transitional area from the GCV to the AIV was 2.45%. Four had PVCs/IVTs from DGCV, 5 from PAIV, and 3 from EDGCV. There were different characteristics of ECG of PVCs/VT originating from the DGCV and PAIV and EDGCV. Successful RFCA in all 12 patients could be achieved (100% acute procedural success). No complications were observed. During a median follow up of 17months (range 6–45months), 2 had recurrent ventricular arrhythmia (recurrence rate: 16.67%). Conclusions ECG characteristics of PVCs/VTs originating from the different portions of the left coronary veins (DGCV and PAIV and EDGCV) are different, and can help regionalize the origin of these arrhythmias. RFCA within the coronary venous system was relatively effective and safe for the PVCs/IVTs and should be seen as an alternative approach, when the left-sided PVCs/IVTs could not be eliminated by RFCA from the endocardium or aortic sinus of Valsalva.

A 35-year-old man was referred to the emergency department after having a short syncopal episode while waiting for a Doppler scan of the lower extremities for a 4-week history of a painful right leg. He had no significant past medical history and was a non-smoker. On presentation he had severe chest pain and dyspnea associated with diaphoresis, and was hemodynamically unstable. His initial electrocardiogram (ECG) showed ST segment elevations in leads V1-4, mimicking an anteroseptal myocardial infarction. However, the angiography showed the coronary arteries were normal and the right main pulmonary artery was partially occluded by large pulmonary emboli. The ECG changes were recorded in detail which also pointed to the diagnosis of pulmonary embolism (PE). This case shows how a PE can mimic an anteroseptal myocardial infarction on ECG, and the physiopathology of the ST elevation in PE was discussed. (Circ J 2009; 73: 1157-1159)

Although pulmonary embolism (PE) complicated by radiofrequency catheter ablation (RFCA) is rare, it can be life-threatening. Our goal was to elucidate the clinical features of acute massive PE after RFCA. Of 2386 patients who underwent RFCA for supraventricular tachycardia or idiopathic ventricular arrhythmia, 4 patients (0.16%) whose cases were complicated by acute massive PE were examined. These 4 patients were female and middle-aged (range 43-52 years), and 2 of the 4 patients had iron-deficiency anemia and reactive thrombocytosis. Ablation in all patients was performed in the left heart via the right femoral arterial approach. All of the patients had a long-duration hemostasis procedure and bed rest following femoral arterial sheath removal after RFCA. All of the patients collapsed and lost consciousness during their frst attempt at walking after RFCA. The emergent electrocardiogram in 2 of the 4 patients revealed an S1Q3T3 pattern, 1 patient demonstrated new onset of right bundle-branch block (RBBB) and S1Q3 pattern and Qr pattern in V1, and the remaining patient had negative T waves in leads V1, V2, and III. The emergent echocardiogram revealed right ventricular hypokinesis and pulmonary hypertension in the 4 patients with acute PE after ablation. Although all of the patients initially experienced sinus tachycardia when they recovered consciousness, 2 of the 4 patients suddenly developed intense bradycardia and lost consciousness again, and these patients finally died (50% fatality rate). All of the patients were identifed by CT pulmonary angiography or pulmonary angiography. Our report suggests that although acute massive PE is highly rare, there is a real and fatal risk in patients who experienced acute massive PE after RFCA. Particular attention should be paid to the first ambulation after RFCA. Acute PE should be strongly suspected when sudden loss of consciousness occurs upon mobilization after RFCA. The new onset of S1Q3T3 pattern, RBBB or T wave inversion in the right precordial leads, and early detection of echocardiographic right ventricular dysfunction may be useful for making an early diagnosis of acute PE after RFCA. Early ambulation after left-sided RFCA might be helpful to prevent the formation of deep venous thrombosis and subsequent PE.

Background In recent years, radiofrequency catheter ablation(RFCA) has been established as an effective therapy for idiopathic premature ventricular contractions (PVCs), however, its effect on the narrow PVCs (QRS duration