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Abstract Background An idiopathic outflow tract premature ventricular complex (OT-PVC) is a common arrhythmia, and the accuracy of site of origin prediction using the 12-lead electrocardiogram (ECG) algorithm is not high. There are no studies about a systematic strategy that can provide practical help to electrophysiologists in OT-PVC mapping and ablation. This study aims to evaluate the efficacy and safety of the proposed ablation protocol and establish an optimal catheter ablation strategy by simultaneously investigating and synthesizing various indicators observed during the mapping procedure. Methods and design This study (ABOUT-PVC) was designed as a prospective multicenter study to enroll 210 patients from 11 tertiary university hospitals over an estimated 27 months. Patients with idiopathic OT-PVC requiring catheter ablation will receive the procedure through a proposed ablation strategy and will be followed up for at least 12 months. The primary outcome is the acute procedural success rate. The secondary outcomes are clinical success rate, procedure time, complication rate, symptom relief, and changes in echocardiographic parameters. Conclusions The ABOUT-PVC study was designed to investigate the efficacy and safety of the proposed ablation strategy and establish an optimal catheter ablation strategy. We expect this study to overcome the limitations of the ECG prediction algorithms and provide a practical guide to electrophysiologists, increasing the procedure’s success rate and reducing complications and procedure time.

Background We hypothesized that analysis of serial ECGs could predict new‐onset atrial fibrillation (AF) more accurately than analysis of a single ECG by detecting the subtle cardiac remodeling that occurs immediately before AF occurrence. Our aim in this study was to compare the performance of 2 types of machine learning (ML) algorithms. Methods and Results Standard 12‐lead ECGs of patients selected by cardiologists between January 2010 and May 2021 were used for ML model development. Two ML models (single ECG and serial ECG) were developed using a light gradient boosting machine‐learning algorithm. Model performance was evaluated based on the area under the receiver operating characteristic curve, sensitivity, specificity, accuracy, and F1 score. We trained the ML models on 415 964 ECGs from 176 090 patients. When testing the 2 ML models using external validation data sets, the performance of the serial‐ML model was significantly better than that of the single‐ML model for predicting new‐onset AF (single‐ versus serial‐ML model: sensitivity 0.744 versus 0.810; specificity 0.742 versus 0.822; accuracy 0.743 versus 0.816; F1 score 0.743 versus 0.815; area under the receiver operating characteristic curve 0.812 versus 0.880; P

Background: The ideal long-term antithrombotic strategy for patients after successful catheter-based atrial fibrillation (AF) ablation is still uncertain. Presently, practices vary, and the advantages of oral anticoagulation (OAC) for the post-ablation population are not clearly established. To date, no randomized trials have addressed this therapeutic question. This study aimed to evaluate whether no OAC therapy is superior to apixaban in reducing the risk of stroke, systemic embolism, or major bleeding among patients without apparent recurrent atrial arrhythmias for at least 1 year after their AF ablation procedure. Methods: The ALONE-AF trial is a prospective, multicenter, open-label, randomized study with blinded outcome assessment. Patients with AF who have at least one non-gender stroke risk factor (as determined by the CHA2DS2-VASc score) and no documented recurrences of atrial arrhythmia for at least 12 months post-ablation will be randomly assigned to apixaban 5 mg b.i.d. or no OAC therapy. The primary endpoint is a composite outcome of stroke, systemic embolism, and major bleeding. Key secondary outcomes include clinically relevant non-major bleeding, all-cause mortality, myocardial infarction, transient ischemic attack, quality of life, and frailty analysis. Participants will be followed for a period of 2 years. The estimated total sample size is 840 subjects, with 420 subjects in each arm. Conclusion: The ALONE-AF trial aims to provide robust evidence for the optimal anticoagulation strategy for patients with stroke risk factors following successful AF ablation.

Background/Aims Atrial fibrillation (AF) is a common arrhythmia and is associated with cardiovascular morbidity and mortality. It is important to identify and control the modifiable risk factors of AF. We aimed to examine the association of exercise capacity with the risk of incident AF within 3 years in healthy subjects. Methods We evaluated asymptomatic adults who had undergone more than two consecutive health checkups. We included subjects who exhibited normal sinus rhythm on the first health examination and who developed AF on the second or subsequent health examinations. Subjects who underwent cardiopulmonary exercise testing within 3 years before the diagnosis of AF were examined. Results The study population in the analyses included 428 cases (mean age 58.4 ± 7.6 yr, male 95.6%). There were significant differences in maximal systolic blood pressure (SBP; case 169.4 ± 24.2 vs. control 173.9 ± 22.3 mmHg), peak VO2 (29.5 ± 5.4 vs. 30.4 ± 4.8 mL/kg per minute), and maximal metabolic equivalents (METs; 8.5 ± 1.6 vs. 8.7 ± 1.4) between the two groups. In the multivariable logistic models, adjusted odds ratios were 0.99 for maximal SBP (95% confidence interval [CI] 0.98–0.99), 0.97 for peak VO2 (95% CI 0.95–0.99), and 0.91 for maximal METs (95% CI 0.83–0.98). Conclusions We demonstrated that poorer exercise capacity was associated with the development of AF in a healthy population. A prospective, systematic trial is necessary to confirm that appropriate exercise training will be beneficial in preventing the development of AF in such patients.

Background The ECG is a simple, noninvasive screening method for cardiovascular disease and arrhythmia. The impact of ECG abnormality on mortality is not certain in low‐risk populations. To address this, we evaluated the association between ECG abnormality and mortality. Methods and Results We retrospectively assessed baseline ECG and all‐cause mortality and cardiovascular mortality in 660 383 patients presenting for medical check‐ups. Baseline ECG abnormalities were classified according to the Minnesota Code. Among the total 660 383 participants, 23 609 (3.6%) had major and 110 038 (16.7%) had minor ECG abnormalities. All‐cause mortality occurred in 7751 patients (1.1%) and cardiovascular mortality in 1180 (0.18%) over a median follow‐up period of 8.8 years. Major ECG abnormalities were associated with all‐cause mortality (hazard ratio [HR], 1.11 [95%, 1.03–1.2]) and cardiovascular mortality (HR, 1.92 [95% CI, 1.63–2.27]) compared with no ECG abnormalities. All‐cause mortality was associated with right atrial enlargement (HR, 2.11 [95% CI, 1.1–4.07]), left atrial enlargement (HR, 1.76 [95% CI, 1.1–2.84]), sinus tachycardia (HR, 1.52 [95% CI, 1.15–2.01]), complete atrioventricular block (HR, 2.1 [95% CI, 1.05–4.2]), atrial fibrillation (HR, 1.52 [95% CI, 1.26–1.84]), and left ventricular hypertrophy (HR, 1.15 [95% CI, 1.02–1.3]). Cardiovascular mortality was associated with left atrial enlargement (HR, 4.52 [95% CI, 2.15–9.5]), atrial fibrillation (HR, 3.22 [95% CI, 2.33–4.46]), left ventricular hypertrophy (HR, 1.72 [95% CI, 1.35–2.19]), major Q‐wave abnormality (HR, 1.6 [95% CI, 1.08–2.39]), and major ST‐T abnormality (HR, 1.76 [95% CI, 1.01–3.04]). Conclusions ECG abnormalities, including left atrial enlargement, left ventricular hypertrophy, atrial fibrillation, and major Q‐wave and ST‐T abnormalities, were associated with cardiovascular mortality in a low‐risk population.

Abstract Background In patients with non-paroxysmal AF (atrial fibrillation), various ablation strategies have been attempted to target non-pulmonary vein (PV) foci or to achieve substrate modification beyond pulmonary vein isolation. The efficacy of empirical ablation of the SVC, one of the most common non-PV foci, is unclear. The aim of this study was to investigate the efficacy and safety of additional superior vena cava (SVC) isolation in patients with non-paroxysmal AF undergoing thoracoscopic surgical ablation. Methods/results A total of 191 patients with persistent or long-standing persistent AF was enrolled. All patients underwent total thoracoscopic surgical ablation for AF, and half of them also received empirical SVC isolation. We compared the atrial tachyarrhythmia (ATa)-free survival rate and procedure-related complications in the two groups of patients. The 3-year ATa-free survival rate was 53% in the SVC isolation group and 52% in the no-SVC isolation group (p = 0.644). There were no differences between the two groups with respect to AF type or LA size. Procedure-related complications occurred in 12 patients (6%). Pacemakers were implanted only in three patients from the SVC isolation group. The only factor influencing recurrence of ATa was LA diameter. Conclusions Empirical SVC isolation during thoracoscopic ablation for persistent AF did not improve patient outcomes.

Atrial fibrillation (AF) is a leading cause of cardioembolic stroke, which is often fatal or disabling. Prevention of stroke is crucial in AF management, and anticoagulation with non-vitamin K oral anticoagulants (NOACs) is the mainstay of AF management for stroke prevention. Because NOAC prescriptions have been surging worldwide, the development of acute ischemic stroke in patients with AF who receive NOAC treatment is an increasingly important issue in clinical practice. Moreover, these patients show a high risk of recurrence, with more than a 50% higher risk, than do patients with AF and no prior anticoagulation therapy. Careful evaluation is mandatory to determine possible causes of ischemic stroke during NOAC therapy. Differentiation of AF-unrelated stroke and demonstration of combined cardiac disease/systemic coagulopathy are important in these patients and may provide improved results in their treatment. In addition, ensuring appropriate dosing and good adherence to NOAC treatment is important. Cardioembolism, despite sufficient anticoagulation and no other causes, is the most common and challenging complication because switching to anticoagulants or adding antiplatelets to the treatment regimen does not reduce the risk of recurrent stroke, and there are no guidelines for this specific situation. This review article aimed to present the most updated data on the prevalence, causes, and secondary prevention strategies, specifically focusing on non-pharmacological approaches, together with relevant cases of AF in patients who developed ischemic stroke on NOAC therapy.

Abstract Background The association between bundle branch block (BBB) and recurrence of atrial fibrillation (AF) after catheter ablation is unclear. The aim of this study was to determine whether AF combined with BBB is associated with AF recurrence after catheter ablation. Methods A total of 477 consecutive AF patients who underwent catheter ablation were included. The AF patients were divided into three groups according to BBB: AF without BBB (n = 427), AF with right bundle branch block (AF with RBBB) (n = 16), and AF with intraventricular conduction delay (AF with IVCD) (n = 34). Results Of the 477 AF patients (mean age 57 years, 81% men, median CHA2DS2‐VASc score of 1), 16 (3.4%) patients had RBBB, and 34 (7.1%) patients had IVCD. During a mean follow‐up of 15.2 ± 6.7 months, 119 patients (24.9%) had recurrence of AF. Of these, 111 (26%) patients were in the AF without BBB group, with 2 (12.5%) and 6 (17.6%) patients in the RBBB and IVCD groups, respectively. The Kaplan–Meier estimate of the rate of recurrent AF was not significantly different among the three groups (p = .39). Multivariable analysis showed that persistent AF (HR 1.7, 95% CI 1.15–2.50, p = .007), chronic kidney disease (HR 2.94, 95% CI 1.20–7.17, p = .01), and left atrial diameter (HR 1.04, 95% CI 1.009–1.082, p = .01) were significantly associated with AF recurrence. Conclusion AF with BBB was not significantly associated with the recurrence of AF after catheter ablation in middle‐aged patients with low‐risk cardiovascular profile.

Abstract Background An exponential rise in clinical demand for cardiac implantable electronic device (CIED) therapy is observed all over the world due to the rapidly expanding lifespan. Accordingly, appropriate lead management including lead extraction is becoming increasingly essential components for the comprehensive care of patients with various CIEDs. Main body With a high success rate and a low complication rate, transvenous lead extraction (TLE) has now been established as first-line therapy for lead extraction. However, TLE is often challenging when there are heavily calcified fibrous adhesions between leads and cardiovascular structures. Recently, rotational mechanical dilator (RMD) sheaths were introduced to resolve this issue and facilitate TLE procedure. There are two types of commercially available RMD sheaths, Evolution® systems and TightRail™. Thorough knowledge of the proper use of the RMD devices is essential to increase success rate and to reduce complications of TLE. In the present review, mechanical features, various techniques, and clinical data of RMD sheaths will be described. Conclusion According to recent advancement of device technology, the clinical outcomes of TLE using the RMD sheaths are continuously improving. However, as the RMD sheath is a potentially aggressive tool, special care should be taken when used in patients with longer lead ages. Author names: Please confirm if the author names are presented accurately and in the correct sequence (given name, family name). Author 2 Given name: Ju Youn, Family name: Kim; Author 4 Given name: Young Keun, Family name: On; Author 5 Given name: June Soo, Family name: Kim. Also, kindly confirm the details in the metadata are correct.All of the author names are correct.

Abstract Background Atrial fibrillation (AF) is a well-known, long-term complication of atrial septal defect (ASD) in adults, even after device closure. Left atrial (LA) strain rate applied to the analysis of chamber function has been demonstrated to be an important predictor of LA reverse remodeling. This study aimed to determine the changes in chamber function after device closure of ASD. Methods This prospective study enrolled adults with secundum ASD undergoing transcatheter device closure from December 2016 to August 2017. We analyzed the clinical characteristics and LA strain rate before and six months after ASD closure. Results A total of 11 patients were enrolled. The mean age was 42.6 ± 9.9 years, and six (54.5%) were females. There was no significant change of conventional echocardiographic parameters after ASD closure. The mean global LA reservoir strain rate before ASD closure was 1.17 ± 0.34 and 0.85 ± 0.30 after ASD closure (p = 0.030). The median global LA conduit strain rate was 0.68 (0.42–1.16) and 0.41 (0.16–0.79) before and after ASD closure (p = 0.213), respectively. The mean global LA contractile strain rate at the six-month follow-up showed significant improvement compared with pre-procedural strain rate (0.33 ± 0.65 vs. − 0.43 ± 0.38, p = 0.006). Conclusions LA functional changes occurred during the six-month follow-up, while LA and right atrial (RA) geometric changes were not significant. LA reverse remodeling was proved by restoration of LA late diastolic contractile function.

Abstract It is unclear which factors are associated with progressive sinus node dysfunction after cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) ablation. We sought to evaluate the incidence and predictors for permanent pacemaker (PPM) implantation after CTI-dependent AFL ablation. Between January 2011 and June 2021, 353 patients underwent CTI-dependent AFL ablation were studied. During a median follow-up of 31.6 months, 30 patients (8.5%) received PPM implantation, 24 for sick sinus syndrome and 6 for atrioventricular block. In multivariable model, prior atrial fibrillation (AF) (HR 3.570; 95% CI 1.034–12.325; P = 0.044), lowest previous sinus heart rate (HR 0.942; 95% CI 0.898–0.988; P = 0.015), and left atrial volume index (LAVI) (HR 1.067; 95% CI 1.024–1.112; P = 0.002) were independently associated with PPM implantation after CTI-dependent AFL ablation. The best cut-off points for predicting PPM implantation were 60.1 ml/m2 for LAVI and 46 beats per minute for lowest previous sinus heart rate. Among the patients discharged without PPM implantation after ablation, sinus pause over three seconds at AFL termination during ablation was an independent predictor of PPM implantation (HR 17.841; 95% CI 4.626–68.807; P

Abstract As the indications for catheter-based electrophysiologic procedures become more diverse and complex, accurate assessment of the anatomy of intracardiac structure has become essential for the optimal clinical outcome. Since intracardiac echocardiography (ICE) was first introduced in 1980, it has become an integral part of various electrophysiologic procedures enabling accurate visualization of cardiac structures and continuous monitoring of catheter position, with integration of real-time images and electroanatomic mapping. Catheter ablation for outflow tract ventricular arrhythmias (OTVAs) has been actively performed in symptomatic patients. However, the anatomic complexity of OT serves as the biggest obstacle to obtain the optimal results. In OTVAs, ICE has played an invaluable role in precisely defining the anatomic shell of OT beyond fluoroscopy and in guiding catheter manipulation in relation to critical structures like the conduction system and coronary arteries. This review article provides detailed information on comprehensive application of ICE for catheter ablation of OTVAs.

Objectives: Heart rate turbulence (HRT) and T-wave alternans (TWA), non-invasive markers of cardiac autonomic dysfunction, and ventricular repolarization abnormality, reportedly, predict the risk of cardiovascular death after myocardial infarction. We investigated whether pre-operative assessment of HRT and/or TWA could predict long-term mortality following coronary artery bypass graft (CABG) surgery. Methods: From May 2010 to December 2017, patients undergoing elective CABG and receiving 24 h ambulatory electrocardiogram monitoring 1 to 5 days prior to CABG surgery were prospectively enrolled. Pre-operative HRT and TWA were measured using a 24 h ambulatory electrocardiogram. The relative risk of cardiac or overall death was assessed according to abnormalities of HRT, TWA, or left ventricular ejection fraction (LV EF). Results: During the mean follow-up period of 4.6 ± 3.9 years, 40 adjudicated overall (5.9%/yr) and 5 cardiac deaths (0.9%/yr) occurred in 146 enrolled patients (64.9 ± 9.3 years; 108 males). Patients with abnormal HRT exhibited significantly higher relative risks of cardiac death (adjusted hazard ratio [HR] 24.9, 95% confidence interval [CI] 1.46–427) and all-cause death (adjusted HR 5.77, 95% CI 2.34–14.2) compared to those with normal HRT. Moreover, abnormal HRT plus abnormal TWA and LV EF < 50% was associated with a greater elevation in cardiac and overall mortality risk. The predictive role of abnormal HRT with/without abnormal TWA for all-cause death was likely more prominent in patients with mildly reduced (35 to 50%) or preserved (≥50%) LV EF. Abnormal HRT plus abnormal TWA and LV EF < 50% showed high negative predictive value in cardiac and overall mortality risk. Conclusions: Assessment of pre-operative HRT and/or TWA predicted mortality risk in patients undergoing elective CABG. Combined analysis of HRT, TWA, and LVEF enhanced the prognostic power. In particular, the predictive value of HRT was enhanced in patients with preserved or mid-range LV EF.

Abstract The need for transvenous lead extraction (TLE) is increasing worldwide including in Asia–Pacific regions. However, supporting evidence for TightRail, a relatively new rotating mechanical dilator sheath, is still lacking in Asian patients. The efficacy and safety of TLE using TightRail performed between March 2018 and June 2021 were evaluated in 86 consecutive patients with 131 leads. The mean lead age was 11.7 ± 7.3 (range, 1.0–41.4) years. Clinical and complete procedural success using TightRail were achieved in 93.0% and 89.5% of 86 patients, respectively, with 6 min of median fluoroscopic time and 9.3% of major complication rate: death (1.2%), cardiac tamponade (3.5%), severe tricuspid regurgitation (3.5%), and stroke (1.2%). However, in 46 patients with longest lead age ≤ 10 years, clinical/complete success and major cardiac complication rates turned out better as 97.8%, 95.7%, and 2.2%, respectively. Additionally, when patients were divided into 3 groups: the first 28, second 29, and the last 29 patients, there was a clear trend toward better efficacy and safety outcomes with more experience with TightRail (Ptrend 10 years was closely associated with TLE-related major cardiac complication (P = 0.046) with 85.7% sensitivity, 57.0% specificity, 15.0% positive predictive value, and 97.8% negative predictive values. In conclusion, TLE using TightRail may be effectively and safely performed by experienced operators for Asian patients with the longest lead age ≤ 10 years. However, as TightRail is a potentially aggressive tool, special attention should be paid to patients with longer lead dwelling times (e.g., > 10 years).

ABSTRACT While long‐distance running has important health benefits, chronic elevation of blood pressure during exercise might induce cardiac events and sudden death. This study aimed to investigate characteristics of exercise and incidence of abnormal exercise electrocardiography findings in long‐distance runners with exercise‐induced hypertension. Long‐distance runners (n = 606) underwent a questionnaire survey, history taking, and exercise stress testing, and they were classified into the non‐exercise‐induced (n = 268) and exercise‐induced (n = 338) hypertension groups. Exercise‐induced hypertension was defined as systolic blood pressure ≥210 mm Hg during maximal exercise. Abnormal electrocardiogram response (AER) were defined as abnormal electrocardiography findings, such as arrhythmias or ST‐segment changes, during exercise stress testing. There were no differences in general and exercise‐related characteristics between the non‐exercise‐induced and exercise‐induced hypertension groups. The AER group (AERg, n = 37) had a significantly longer training history and total exercise time than the non‐AER group (non‐AERg, n = 569) (p

Background Atrial fibrillation (AF) is associated with an increased risk of poor cardiovascular outcomes; appropriate rhythm control can reduce the incidence of these adverse events. Therefore, catheter ablation is recommended in symptomatic patients with AF. The aims of this study were to compare AF‐related outcomes according to a baseline symptom scale score and to determine the best treatment strategy for asymptomatic patients with AF. Methods and Results This study enrolled all patients who completed a baseline Atrial Fibrillation Effect on Quality‐of‐Life (AFEQT) survey in a prospective observational registry. The patients were divided into 2 groups according to AFEQT score at baseline; scores ≤80 were defined as symptomatic, whereas scores >80 represented asymptomatic patients. The primary outcome was defined as a composite of hospitalization for heart failure, ischemic stroke, or cardiac death. This study included 1515 patients (mean age: 65.7±10.5 years; 998 [65.9%] men). The survival curve showed a poorer outcome in the symptomatic group compared with the asymptomatic group (log‐rank P=0.04). Rhythm control led to a significantly lower risk of a composite outcome in asymptomatic patients (hazard ratio [HR], 0.47 [95% CI, 0.27–0.84], P=0.01). Rhythm control was associated with more favorable composite outcomes in the asymptomatic group with paroxysmal AF, left atrium diameter ≤50 mm, and CHA2DS2‐VASc score ≥3. Conclusions Symptomatic patients with AF experienced more adverse outcomes compared with asymptomatic patients. In asymptomatic patients with AF, a strategy of rhythm control improved the outcomes, especially with paroxysmal AF, smaller left atrium size, or higher stroke risk. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02786095.

BackgroundSubclinical atrial fibrillation (AF) is one of the pathogeneses of embolic stroke. Detection of occult AF and providing proper anticoagulant treatment is an important way to prevent stroke recurrence. The purpose of this study was to determine whether an artificial intelligence (AI) model can assess occult AF using 24-h Holter monitoring during normal sinus rhythm.MethodsThis study is a retrospective cohort study that included those who underwent Holter monitoring. The primary outcome was identifying patients with AF analyzed with an AI model using 24-h Holter monitoring without AF documentation. We trained the AI using a Holter monitor, including supraventricular ectopy (SVE) events (setting 1) and excluding SVE events (setting 2). Additionally, we performed comparisons using the SVE burden recorded in Holter annotation data.ResultsThe area under the receiver operating characteristics curve (AUROC) of setting 1 was 0.85 (0.83–0.87) and that of setting 2 was 0.84 (0.82–0.86). The AUROC of the SVE burden with Holter annotation data was 0.73. According to the diurnal period, the AUROCs for daytime were 0.83 (0.78–0.88) for setting 1 and 0.83 (0.78–0.88) for setting 2, respectively, while those for nighttime were 0.85 (0.82–0.88) for setting 1 and 0.85 (0.80–0.90) for setting 2.ConclusionWe have demonstrated that an AI can identify occult paroxysmal AF using 24-h continuous ambulatory Holter monitoring during sinus rhythm. The performance of our AI model outperformed the use of SVE burden in the Holter exam to identify paroxysmal AF. According to the diurnal period, nighttime recordings showed more favorable performance compared to daytime recordings.

ObjectivesAtrial fibrillation (AF) is associated with an increased ischemic stroke, and the left atrial appendage (LAA) represents the main source of thrombus formation. We evaluated the long-term efficacy of surgical thoracoscopic LAA occlusion during total thoracoscopic ablation of AF to prevent the stroke and anticoagulation strategy after surgery.MethodsPatients who underwent total thoracoscopic ablation for AF, from February 2012 to May 2020, were included; Patients who did not receive LAA occlusion were excluded. We evaluated the development of thromboembolism in these patients.ResultsThe total number of 460 patients [mean age, 57.1 ± 9.2 years; 400 (87.0%) males] were included in the study. The mean follow-up duration was 44.8 months. The mean CHA2DS2-VASc score was 1.9 ± 1.6. Median OAC duration was 109.5 days after the surgery, and the final number of patients who discontinued OAC were 411 (89.3%) in total. Anticoagulation discontinuation rate according to CHA2DS2-VASc score are as follows; (i) 0 = 99.0%; (ii) 1 = 98.2%; and (iii) ≥2 = 81.3%. The annualized incidence rate of ischemic stroke was 0.78%/year, showing a 73% risk reduction compared with the CHA2DS2-VASc predicted rate without anticoagulation. The hazard ratio for ischemic stroke according to previous stroke history was 1.5 [95% confidential interval (CI) 0.3–7.3, p = 0.62], and that of remnant LAA was 5.1 (1.2–20.9, p = 0.02).ConclusionsThoracoscopic LAA occlusion during total thoracoscopic ablation of AF was effective to prevent ischemic stroke. Most patients could discontinue OAC therapy after the procedure. Patients who had a residual trabeculated LAA, or peri-occluder pouch in follow-up CT need to maintain OAC therapy even after LAA occlusion.

Abstract Aims We sought to evaluate the effectiveness of cardiac resynchronization therapy (CRT) in far‐advanced heart failure (FA‐HF) patients with New York Heart Association (NYHA) class‐IV status and dependency on intravenous drugs (IVDs) and/or invasive supportive treatments (ISTs). Methods and results Among 305 patients who underwent CRT implantation between October 2005 to December 2019, we identified 17 FA‐HF patients with NYHA class‐IV status and dependency on IVDs (inotropes, diuretics, vasopressors, or vasodilators) and/or ISTs (extracorporeal membranous oxygenator or continuous renal replacement therapy). All patients (median age = 68.7 years, non‐ischaemic cardiomyopathy = 15) remained dependent on several IVDs (2.2 ± 1.3 per patient) and/or ISTs for 11.3 ± 7.8 days due to multiple tapering failure (4.3 ± 3.2 per patient) before CRT implantation. However, 14 (82%) patients were successfully weaned from IVDs/ISTs within 5.2 ± 5.3 days following CRT, and 12 (71%) stayed alive for more than 1 year free of ventricular assist device or heart transplantation with symptom improvement (≥1 NYHA class) and a reduced annual HF hospitalization rate (P = 0.002). Considerable improvements in ventricular systolic function (P = 0.004) and volumetric reverse remodelling (P = 0.007) were noticed during the long‐term follow‐up period (35 ± 15 months post‐CRT). The ventricular assist device/heart transplantation/death‐free survival rate post‐CRT was 71% and 65% at 1 and 3 years, respectively. Conclusions Cardiac resynchronization therapy implantation may be a feasible treatment that can offer short‐term and long‐term clinical benefits for NYHA class‐IV FA‐HF patients who are dependent on IVDs/ISTs. When considering treatment options, CRT should not be prematurely excluded solely based on a patient's dependency on IVDs/ISTs without first attempting to identify favourable CRT response factors.

Abstract Background Frequent ventricular premature depolarizations (VPDs) can cause reversible cardiomyopathy (CMP). However, many patients maintain a normal left ventricular (LV) function with a high VPD burden. The electrocardiographic characteristics of VPD‐induced CMP have not been elucidated. Methods One hundred and eighty (91 men, age; 51 ± 15 years) patients with frequent idiopathic VPDs (>10% VPDs/day or >10 000 VPDs/day) were studied. All patients underwent successful ablation and were then divided into two groups according to the echocardiographic findings before and after the ablation procedure. Results Group A (n = 139) had a normal LV function with VPD frequencies, and Group B (n = 41) had reversible LV dysfunction after ablation. The VPD QRS duration (QRSd) was wider in patients with CMP (Group A vs Group B; 137.2 ± 12.0 milliseconds vs 159.7 ± 5.3 milliseconds, P

Background Cryoballoon ablation was established as an effective and safe modality to achieve pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (PAF). However, its role in persistent atrial fibrillation (PersAF) remains unclear. Objective This study aimed to evaluate the efficacy and safety of cryoballoon PVI in PAF and PersAF comparing conventional radiofrequency catheter ablation (RFCA). Methods Two hundred patients undergoing cryoballoon ablation for symptomatic AF were consecutively enrolled in this retrospective study. For comparison, 210 patients undergoing RFCA in the same period were included. The primary outcome was a recurrence of any atrial tachyarrhythmias (ATas) after the index ablation. 12-lead ECG and 24-hour Holter monitoring were obtained at 1,3,6 and 9–12 months. Results PVI by cryoablation alone was achieved in 197 patients (98.5%). ATas-free survival at 12 months post-ablation was 72.7% in the cryoablation and 80.6% in the RFCA group (P = 0.123), respectively. The cryoablation showed comparable efficacy maintaining sinus rhythm compared with RFCA in PAF (P = 0.539), whereas in PersAF, ATas-free survival was significantly lower in cryoablation (P = 0.039). PV reconnection was observed in the majority of patients (14/16, 87.5%) who receive redo RFCA. Complications were encountered in 10 patients, including femoral arteriovenous fistula (n = 1), transient phrenic nerve palsy (n = 8), and minimal amount pericardial effusion (n = 1). Conclusion The efficacy of cryoballoon PVI is comparable with conventional RFCA in PAF, whereas PVI alone using cryoballoon may not be insufficient to maintaining sinus rhythm in PersAF. The safety of cryoballlon PVI is tolerable.

Abstract Background and objectives The association between thyroid dysfunction and supraventricular tachyarrhythmia (SVT) other than atrial fibrillation (AF) is not well elucidated. We hypothesized that patients with suspected or documented SVT have undetected thyroid dysfunction more frequently than general population. Subjects and methods Patients with symptoms suggestive of SVT other than AF who were planned to undergo an EP study at our center were eligible for this study. Patients with known thyroid disease, medications affecting thyroid function test (TFT) or atrial fibrillation were excluded. The primary outcome was prevalence of TFT abnormalities in the study population. The secondary outcome was prevalence of clinically significant arrhythmia during the EP study. Results A total of 533 patients were analyzed. Patients were divided into the two groups according to TFT results. Fifty-six (10.5%) patients had abnormal TFT results (thyroid dysfunction group), while 477 (89.5%) had normal thyroid function (euthyroidism group). The overall prevalence of thyroid dysfunction was 10.5%. The thyroid dysfunction group showed a tendency for higher induction of clinically significant SVT than the euthyroidism group. However, thyroid dysfunction was not an independent predictor of clinically significant SVT during EP study. Conclusion In this study, patients with suspected SVT who were planned for EP study had a relatively high incidence of thyroid dysfunction. Clinically significant arrhythmia tended to be induced more frequently in the thyroid dysfunction group than in the euthyroidism group. Further investigations are needed to verify the clinical implications of TFT in patients with SVT other than AF.

Abstract Background Electrical cardioversion (ECV) is an effective method for restoring sinus rhythm after atrial fibrillation (AF). However, early recurrence of AF occurs in a significant number of patients after ECV. This study aimed to identify electrocardiographic (ECG) predictors of early AF recurrence after ECV. Methods A total of 272 patients with persistent AF undergoing successful ECV were consecutively enrolled in this study. We investigated clinical, echocardiographic, and ECG data. The 12‐lead ECG parameters were measured during sinus rhythm right after ECV using a digital caliper. The early AF recurrence was defined as recurrence within 2 months. Results Of the 272 patients, 165 patients (60.7%) experienced an early AF recurrence. Maximum P‐wave duration (PWD) in limb leads (OR: 1.086; 95% CI: 1.019–1.157; p = .012) and P‐terminal force (PTF) in V1 (OR: 1.019; 95% CI: 1.004–1.033; p = .011) were independent predictors of early AF recurrence after ECV. The optimal cutoff value of the maximum PWD in limb leads for predicting early AF recurrence was 134 ms, characterized by 90.3% sensitivity and 72.0% specificity. Likewise, the optimal cutoff value of PTF in V1 was 50 ms × mm, characterized by 80.0% sensitivity and 64.5% specificity. Conclusion A longer PWD (>134 ms) and a larger PTF (>50 ms × mm) were useful predictors of early recurrence of AF after successful ECV in clinical practice. A more effective rhythm control therapy such as catheter ablation or rate control strategy rather than a repeat ECV should be considered.

Background: Totally thoracoscopic ablation (TTA) is a minimally invasive and safe alternative to radiofrequency catheter ablation (RFCA) for patients with atrial fibrillation (AF). It has evolved over the last decades, but data are limited. The aim of this study was to report the long-term efficacy and safety of TTA through a single center experience. Methods: We retrospectively analyzed all consecutive patients who underwent TTA for AF from February 2012 to December 2018. All patients were followed every 3 months after operation with 12-lead ECG and 24-hour Holter ECG monitoring. The late recurrence of AF was defined as any atrial tachyarrhythmia (ATa) sustained more than 30 s from 3 months after surgery. Results: Of the total 408 patients undergoing TTA, 265 were analyzed in this study (17% paroxysmal, persistent or long standing persistent 83%, mean age 56 ± 9 years). During the mean follow-up duration 23 ± 18 months, ATa-free survival rate was 74%, 64%, 58%, 51% and 51% at 1,2,3,4 and 5 years, respectively. At the last follow-up, 75% of patients had sinus rhythm with or without additional intervention. The overall complication rate was 4.5% (12 events) and four patients (1.5%) had a stroke during follow-up. Conclusions: TTA could be effective treatment option for AF. It had a very low risk of complication and could reduce stroke incidence. Further studies are needed to improve treatment strategy.

Neurally mediated syncope (NMS) is a common clinical problem. The underlying genetic factors of NMS remain controversial. We hypothesized that cardiac syncope-related genes may contribute to NMS in patients with previous frequent syncopal episodes and/or a family history of syncope. A total of 54 consecutive patients diagnosed with NMS were prospectively enrolled between 2013 and 2016. Inclusion criteria were more than five syncopal episodes with a family history of syncope (n = 17) or more than five syncopal episodes with no family history of syncope (n = 37). Ninety-eight cardiac syncope-related genes (channelopathy: 43 genes, cardiomyopathy: 50 genes, primary pulmonary hypertension: 5 genes) were screened by exome sequencing. All identified variants were classified according to the standards and guidelines by the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Of the 54 patients, 17 patients (31.5%) had a family history of syncope. Two patients (3.7%) had pathogenic and likely pathogenic variants (PV/LPV) in cardiac syncope-related genes TTN and MYH7. We investigated genetic variation in patients with frequent NMS with a positive family history of syncope in Korea. PV/LPVs in genes related to cardiomyopathy were associated with recurrent NMS in Korean patients. Closer follow-up of these patients might be needed.

(1) Background: Limited data exist on the safety and efficacy of epicardial left ventricular (LV) lead placement using video-assisted thoracoscopic surgery (VATS) for cardiac resynchronization therapy (CRT). (2) Methods: Acute and post-discharge outcomes of CRT were compared between patients with epicardial LV leads (Epicardial-LV group, n = 13) and those with endocardial LV leads (Endocardial-LV group, n = 243). (3) Results: Epicardial LV leads were implanted via VATS alone (n = 8) or along with mini-thoracotomy (n = 5), for failed endocardial implantation (n = 11) or recurrent lead dislodgement (n = 2). All epicardial procedures under general anesthesia with one-lung ventilation were successfully completed in 1.0 ± 0.4 h without phrenic nerve stimulation. LV pacing thresholds in the epicardial-LV (1.5 ± 1.0 V) and endocardial-LV (1.3 ± 0.8 V) were comparable (p = 0.651). All patients were discharged alive post-VATS 8.8 ± 3.9 days. During the follow-up (34.3 ± 28.6 months), all patients with epicardial LV leads stayed alive except for one cardiac death post-CRT 14 months and one heart transplantation post-CRT 30 months. All epicardial LV leads maintained stable performance without dislodgement/significant changes in pacing threshold/impedance. LV lead dislodgement occurred only in endocardial-LV (7/243, 2.9%). Efficacy in both groups was comparable in terms of QRS narrowing, increase in LV ejection fraction, and survival free of cardiac death, or heart-failure-related hospitalization. (4) Conclusions: Epicardial LV lead placement using VATS can be a safe and effective alternative to endocardial implantation, with comparable acute and post-discharge outcomes achieved by both approaches.

Background and Objectives: The treadmill test (TMT) is a predictive tool for myocardial ischemia. Recently, exercise-provoked ventricular premature contracture (VPC) during TMT was shown to have a relation with coronary artery disease and cardiovascular mortality. Therefore, we evaluate clinical correlates of exercise-provoked VPC and compare the predictive power for myocardial ischemia and cardiovascular events. Method: Data of 408 patients (≥18 years of age) who underwent TMT for work up of angina, palpitation, dyspnea, syncope, or arrhythmia between February 2015, and January 2016, were collected with consent at Samsung Medical Center, Seoul, Republic of Korea. Among total of 408 patients, 208 were excluded according to the previous history of PCI or CABG, previous MI, decreased left ventricular ejection fraction lower than 50%, arrhythmia that could affect ST-segment change on ECG. Results: Among 200 patients, 32 (16.0%) developed exercise-provoked VPC (21 patients in the exercise phase, 20 patients in the recovery phase). Of them, 20 patients (10.0%) showed positive TMT, and 4 patients (2.0%) underwent revascularization after TMT. Among 21 patients showing exercise phase VPC, 5 (23.8%) showed positive TMT results. In patients younger than 65 years, exercise phase VPC was associated with positive TMT (odds ratio 6.879, 1.458–32.453) considering demographics and previous medical history in multivariable analysis. Among the 20 patients showing recovery phase VPC, 2 (10.0%) underwent revascularization after TMT. In multivariable analysis, recovery phase VPC was associated with revascularization (odds ratio 9.381, 1.144–76.948) considering age, sex, BMI, and TMT result. Conclusion: VPC during the treadmill test was a useful predictor of myocardial ischemia in this study.

Temporary pacemakers (TPMs) are usually inserted in an emergency situation. However, there are few reports available regarding which route of access is best or what the most preferred approach is currently in tertiary hospitals. This study aimed to compare procedure times, complication rates, and indications for temporary pacing between the transjugular and transfemoral approaches to TPM placement. We analyzed consecutive patients who underwent TPM placement. Indications; procedure times; and rates of complications including localized infection, any bleeding, and pacing wire repositioning rates were analyzed. A total of 732 patients (361 treated via the transjugular approach and 371 treated via the transfemoral approach) were included. Complete atrioventricular block was the most common cause of TPM placement in both groups, but sick sinus syndrome was especially common in the transjugular approach group. Separately, procedure time was significantly shorter in the transjugular approach group (9.0 ± 8.0 minutes vs. 11.9 ± 9.7 minutes; P < 0.001). Overall complication rates were not significantly different between the two groups, and longer duration of temporary pacing was a risk factor for repositioning. The risk of reposition was significantly increased when the temporary pacing was continued more than 5 days and 3 days in the transjugular approach group and the transfemoral approach group, respectively. The transjugular approach should be considered if the TPM is required for more than 3 days.

Background and Objectives: Cryoballoon ablation (CBA) and totally thoracoscopic surgical ablation (TTA) have emerged as alternatives to radiofrequency catheter ablation (RFCA) for atrial fibrillation. In this study, we describe our experience comparing patient characteristics and outcomes of RFCA, CBA, and TTA. Materials and Methods: We retrospectively analyzed data from patients who underwent RFCA, CBA, or TTA. Both atrial fibrillation (AF)- and atrial tachyarrhythmia (ATa)-free survival rates were compared using time to recurrence after a 3-month blanking period (defined by a duration of more than 30 s). All patients were regularly followed using 12-lead ECGs or Holter ECG monitoring. Results: Of 354 patients in this study, 125 underwent RFCA, 97 underwent CBA and 131 underwent TTA. The TTA group had more patients with persistent AF, a larger LA diameter, and a history of stroke. The CBA group showed the shortest procedure time (p < 0.001). The CBA group showed significantly lower AF-free survival at 12 months than the RFCA and TTA groups (RFCA 84%, CBA 74% and TTA 85%, p = 0.071; p = 0.859 for TTA vs. RFCA, p = 0.038 for RFCA vs. CBA and p = 0.046 for TTA vs. CBA). There were no significant differences in ATa-free survival among the three groups (p = 0.270). There were no procedure-related adverse events in the RFCA group, but some complications occurred in the CBA group and the TTA group (6% and 5%, respectively). Conclusions: RFCA and CBA are effective and safe as first-line treatments for paroxysmal and persistent AF. In some high-risk stroke patients, TTA may be a viable option. It is important to consider patient characteristics when selecting an ablation method for AF.

In this paper, we propose a hybrid localization algorithm to boost the accuracy of range-based localization by improving the ranging accuracy under indoor non-line-of-sight (NLOS) conditions. We replaced the ranging part of the rule-based localization method with a deep regression model that uses data-driven learning with dual-band received signal strength (RSS). The ranging error caused by the NLOS conditions was effectively reduced by using the deep regression method. As a consequence, the positioning error could be reduced under NLOS conditions. The performance of the proposed method was verified through a ray-tracing-based simulation for indoor spaces. The proposed scheme showed a reduction in the positioning error of at least 22.3% in terms of the median root mean square error compared to the existing methods. In addition, we verified that the proposed method was robust to changes in the indoor structure.

Background: The absence of atrial contraction (AC) after the maze procedure has been reported to cause subsequent annular dilatation and to increase the risk of embolic stroke. We hypothesized that the lack of AC could increase the risk of permanent pacemaker (PPM) implantation in patients undergoing the maze procedure. Methods: In 376 consecutive patients who had undergone a cryo-maze procedure and combined valve operation, recovery of AC was assessed at baseline and at immediate (≤2 weeks), early (≤1 year, 4.6±3.8 months), and late (＞1 year, 3.5±1.1 years) postoperative stages. Results: With a median follow-up of 53 months, 10 patients underwent PPM implantation. Seven PPM implants were for sinus node dysfunction (pauses of 9.6±2.4 seconds), one was for marked sinus bradycardia, and two were for advanced/complete atrioventricular block. The median (interquartile range) time to PPM implantation was 13.8 (0.5–68.2) months. Our time-varying covariate Cox models showed that the absence of AC was a risk factor for PPM implantation (hazard ratio, 11.92; 95% confidence interval, 2.52 to 56.45; p=0.002). Conclusion: The absence of AC may be associated with a subsequent risk of PPM implantation.

It remains unclear as to whether cardiac resynchronization therapy (CRT) would be as effective in patients with atrial fibrillation (AF) accompanied by slow ventricular response (AF-SVR, < 60 beats/min) as in those with sinus rhythm (SR). Echocardiographic reverse remodeling was compared between AF-SVR patients (n = 17) and those with SR (n = 88) at six months and 12 months after CRT treatment. We also evaluated the changes in QRS duration; New York Heart Association (NYHA) functional class; and long-term composite clinical outcomes including cardiac death, heart transplantation, and heart failure (HF)-related hospitalization. Left ventricular pacing sites and biventricular pacing percentages were not significantly different between the AF-SVR and SR groups. However, heart rate increase after CRT was significantly greater in the AF-SVR group than in the SR group (P < 0.001). At six and 12 months postoperation, both groups showed a comparable improvement in NYHA class; QRS narrowing; and echocardiographic variables including left ventricular end-systolic volume, left ventricular ejection fraction, and left atrial volume index. Over the median follow-up duration of 1.6 (interquartile range: 0.8-2.2) years, no significant between-group differences were observed regarding the rates of long-term composite clinical events (35% versus 24%; hazard ratio: 1.71; 95% confidence interval: 0.23-12.48; P = 0.60). CRT implantation provided comparable beneficial effects for patients with AF-SVR as compared with those with SR, by correcting electrical dyssynchrony and increasing biventricular pacing rate, in terms of QRS narrowing, symptom improvement, ventricular reverse remodeling, and long-term clinical outcomes.

BACKGROUND:Prolongation of corrected QT interval (QTc) on the electrocardiogram is associated with cardiac arrhythmia and sudden death. Changes in the QTc (corrected QT) interval before and after liver transplantation (LT) for the treatment of liver cirrhosis (LC) and its association with clinical outcomes have not been fully evaluated. METHODS:From January 2011 to May 2016, consecutive 516 consecutive recipients were enrolled into LT registry and the median follow-up was 31 months (IQR 12-52). Patients with an available electrocardiogram before LT and 1 month after from LT were analyzed. Patients were divided into 2 groups according to prolonged QTc interval. The patient groups were analyzed separately according whether the electrocardiogram was preoperative or postoperative. The primary outcome was all-cause death during the follow-up period. RESULTS:A total of 283 patients were enrolled in the study. In the preoperative QTc prolongation group, there was not a significant rate difference in all-cause mortality in multivariate analysis (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.53-1.66; P = 0.26). However, in the postoperative QTc prolongation group, mortality was significantly increased (HR, 1.78; 95%CI, 1.05-3.03; P = 0.03) in patients who underwent LT. CONCLUSION:In patients who underwent LT for LC, postoperative QTc prolongation on ECG, rather than preoperative, is associated with mortality. Larger clinical trials are needed to support this finding.

The treatment effect of the hybrid procedure, consisting of a thoracoscopic ablation followed by an endocardial radiofrequency catheter ablation (RFCA), is unclear. A total of 117 ablation-naïve patients who underwent either the staged hybrid procedure (n = 72) or RFCA alone (n = 105) for drug-refractory, non-valvular persistent or long-standing persistent atrial fibrillation (AF) were enrolled. The primary outcome is occurrence of total atrial arrhythmia, defined as a composite of AF, sustained atrial tachycardia (AT), and atypical atrial flutter (AFL) after index procedure. The mean age was 52.7 years. Eighty-four percentage of the patients were male. Patients with prior history of stroke and long-standing persistent AF were more prevalent in the hybrid group than RFCA group. The left atrial volume index was larger in the hybrid group (P

The relative efficacy of antiarrhythmic drugs (AADs) after electrical cardioversion are not well established. This study aimed to investigate the efficacies of different AADs for maintaining sinus rhythm (SR) after electrical cardioversion for atrial fibrillation (AF). We selected patients from a retrospective registry including patients admitted for cardioversion between January 2012 and June 2016. The primary outcome was time to AF recurrence during the first year after cardioversion. The secondary outcomes included AF recurrence within 1 month, and first readmission due to heart failure, stroke, or additional non-pharmacological rhythm control. A total of 265 patients were divided into the 4 groups according to AAD type: flecainide (n = 33), propafenone (n = 64), amiodarone (n = 128), and dronedarone (n = 40). During the first year after cardioversion, the AF recurrence-free survival was similar between all AAD groups (69.7% vs. 67.2% vs. 71.9% vs. 80.0%, p = 0.439). About half of all recurrences occurred during the first month. There was no difference in any of the secondary outcomes, although the amiodarone group showed a trend toward more non-pharmacological rhythm control. AAD type was not associated with recurrence in multivariate analysis. In this study, half of all patients received amiodarone after electrical cardioversion. Flecainide, propafenone, amiodarone, and dronedarone showed similar efficacies for maintaining SR after electrical cardioversion. Thus, it might be reasonable to reconsider amiodarone use after cardioversion, since it did not show superior efficacy to the other drugs considered and is associated with potential side effects.

Idiopathic ventricular fibrillation (IVF) can cause sudden cardiac death. Previous studies have reported that J waves and fragmented QRS complexes (f-QRS) are arrhythmogenic markers and predictors of cardiac events. We evaluated the prevalence and clinical significance of J waves and f-QRS in patients with IVF.We studied 81 patients who received an implantable cardioverter defibrillator (ICD) due to IVF between October 1999 and June 2015. We assessed the prevalence of J waves and f-QRS using electrocardiograms (ECGs). Patients were classified into three groups: J wave group (n = 35), f-QRS group (n = 20), or normal ECG group (n = 26). The control group included 81 subjects without heart disease who were matched for age, sex, and race. We compared syncope, sudden cardiac arrest, and appropriate ICD shock between the three groups.The follow-up duration was 4.1 years. J waves and f-QRS were more frequent in patients with IVF than in control subjects (43.2%, 21% vs. 24.7%, 19.7%, P < 0.001). Out of the three groups, clinical cardiac events were most frequent in the f-QRS group (50% vs. 45.7% vs. 11.5%, P = 0.028). A comparison of the combined group of J wave and f-QRS versus the normal ECG group revealed that the combined group had a higher frequency of clinical cardiac events than the normal ECG group (47.3% vs. 11.5%, respectively, P = 0.009).Patients with IVF had higher prevalence of f-QRS or J waves. And patients with f-QRS or J waves were at higher risk of recurrent ventricular fibrillation.

Hypertrophic cardiomyopathy (HCM) is a cardiac disease associated with a high incidence of atrial fibrillation (AF). Recent studies have suggested that interventricular septum thickness may influence the risk stratification of patients with AF. We evaluated the effects of septal hypertrophy on morbidity and mortality in patients with HCM. Patients were followed for a median of 6.1 years and were divided into two groups according to the extent of septal hypertrophy. A total of 1,360 HCM patients were enrolled: 482 (33%) apical or apicoseptal, 415 (28%) asymmetric septal, 388 (27%) basal septal, 38 (2.6%) concentric, and 37 (2.5%) diffuse and mixed type. Ninety-two all-cause deaths and 21 cardiac deaths occurred. The total event rates were significantly higher for patients with HCM with more extensive septal hypertrophy (group A) compared to those with HCM ± focal septal hypertrophy (group B), regardless of type (p