High prevalence and distinctive clinical features of LMNA-associated atrioventricular block in young patients.

BACKGROUND AND AIMS: Atrioventricular block (AVB) is a degenerative disease and more commonly encountered in elderly patients, but unusual and often of unknown etiology in young patients. This study aimed to investigate the potential contributions of genetic variations to AVB of unknown reasons in young patients. METHODS: We enrolled 41 patients aged <55 years with high-degree AVB of unknown etiology whose clinical and genetic data were collected. RESULTS: Genetic variants were identified in 20 (20/41, 48.8%) patients, 11 (11/20, 55%) of whom had LMNA variants including 3 pathogenic (c.961C > T, c.936+1G > T and c.646C > T), 4 likely pathogenic (c.1489-1G > C, c.265C > A, c.1609-2A > G and c.1129C > T) and 3 of uncertain significance (c.1158-3C > G, c.776A > G and c.674G > T). Compared to those without LMNA variants, patients with LMNA variants demonstrated a later age at onset of AVB (41.45 ± 9.89 years vs 32.93 ± 12.07 years, P = .043), had more prevalent family history of cardiac events (81.8% vs 16.7%, P < .000), suffered more frequently atrial (81.8% vs 10.0%, P < .000) and ventricular (72.7% vs 10.0%, P < .000) arrhythmias, and were more significantly associated with enlargement of left atrium (39.91 ± 7.83 mm vs 34.30 ± 7.54 mm, P = .043) and left ventricle (53.27 ± 8.53 mm vs 47.77 ± 6.66 mm, P = .036). CONCLUSIONS: Our findings provide insights into the genetic etiology of AVB in young patients. LMNA variants are predominant in genotype positive patients and relevant to distinctive phenotypic properties.

Current Anticoagulation Statuses among Older Chinese People with Nonvalvular Atrial Fibrillation.

Background: The reported anticoagulation rate may be overestimated among Chinese patients with atrial fibrillation (AF). Therefore, we aimed to understand the current status and time trends of anticoagulation among older people in the Chinese community. Methods: Data were obtained from the physical examination program for the elderly (aged ≥ 65 years) in Guangzhou. During 2017-2020, a total of 31,829, 58,573, 55,483, and 54,845 older people underwent annual physical examinations, respectively, where their general information, AF-related medical history, and use of oral anticoagulants (OACs) were collected for analysis. Results: From 2017 to 2020, the estimated annual prevalence of older people with nonvalvular atrial fibrillation (NVAF) in Guangzhou was 0.99%, 0.92%, 1.05%, and 1.14%, respectively. In patients with high stroke risk (CHA2DS2-VASc score ≥ 2 for males or ≥ 3 for females), the annual anticoagulation rates were 2.83%, 2.05%, 5.29%, and 5.82%, respectively. The proportion of NVAF patients prescribed non-vitamin K antagonist oral anticoagulants (NOACs) increased gradually over the same period (p = 0.004). Males (odds ratios (OR), 1.797; 95% confidence interval (CI), 1.169-2.763; p = 0.008), ages over 75 (OR, 1.858; 95% CI, 1.212-2.849; p = 0.005), low education levels (OR, 1.737; 95% CI, 1.132-2.665; p = 0.011), and lacking the ability for self-care (OR, 4.432; 95% CI, 1.067-18.418; p = 0.041) were less likely to receive OAC therapy. Conclusions: The low anticoagulation rate of older people with NVAF in the Chinese community has not significantly improved in recent years, with only 5.82% of patients with high stroke risk being prescribed OACs. Therefore, it is necessary to establish an appropriate mode of anticoagulant management to improve the current situation.

Etiologies of atrioventricular block in young patients: A single-center study in China.

BACKGROUND: Atrioventricular block (AVB) is common in the elderly and therefore considered to be a degenerative disease of the cardiac conduction system. However, there exist other etiologies contributing to AVB in young patients. This study aimed to determine the etiologies in patients aged before 60 years receiving their first pacemaker implantation for AVB in China. METHODS AND RESULTS: Medical records and diagnostic tests of AVB patients were reviewed to identify the etiologies between 2010 and 2021 at Guangdong Provincial People's Hospital. Eight hundred and twenty-six patients (median age 47 years; 47.9% males) were included. The etiologies were identified in 336 (40.7%) cases, including complications to cardiac surgery (n = 190 [23.0%]), myocarditis (n = 57 [6.9%]), myocardial infarction (n = 25 [3.0%]), complications to catheter-based interventional procedures (n = 21 [2.5%]) and others (n = 43 [5.2%]). AVB caused by myocardial infarction was more common in men (5.8% vs. 0.5%, p < .001), while women received pacing treatment earlier (48 vs. 46 years, p = .019). Men were more likely to suffer from dilated cardiomyopathy (6.6% vs. 2.1%, p = .001) and atrial fibrillation/flutter (23.0% vs. 12.8%, p < .001). The number of first pacemaker implantation increased with age especially among patients with unclear etiologies. CONCLUSION: The etiology of AVB was only determined in approximately 40% of patients receiving their first pacemaker implantation aged before 60 years. The predominance of AVB with unknown etiology and potential gender differences warrants further studies.

First-Line Catheter Ablation of Monomorphic Ventricular Tachycardia in Cardiomyopathy Concurrent With Defibrillator Implantation: The PAUSE-SCD Randomized Trial.

BACKGROUND: Catheter ablation as first-line therapy for ventricular tachycardia (VT) at the time of implantable cardioverter defibrillator (ICD) implantation has not been adopted into clinical guidelines. Also, there is an unmet clinical need to prospectively examine the role of VT ablation in patients with nonischemic cardiomyopathy, an increasingly prevalent population that is referred for advanced therapies globally. METHODS: We conducted an international, multicenter, randomized controlled trial enrolling 180 patients with cardiomyopathy and monomorphic VT with an indication for ICD implantation to assess the role of early, first-line ablation therapy. A total of 121 patients were randomly assigned (1:1) to ablation plus an ICD versus conventional medical therapy plus an ICD. Patients who refused ICD (n=47) were followed in a prospective registry after stand-alone ablation treatment. The primary outcome was a composite end point of VT recurrence, cardiovascular hospitalization, or death. RESULTS: Randomly assigned patients had a mean age of 55 years (interquartile range, 46-64) and left ventricular ejection fraction of 40% (interquartile range, 30%-49%); 81% were male. The underlying heart disease was ischemic cardiomyopathy in 35%, nonischemic cardiomyopathy in 30%, and arrhythmogenic cardiomyopathy in 35%. Ablation was performed a median of 2 days before ICD implantation (interquartile range, 5 days before to 14 days after). At 31 months, the primary outcome occurred in 49.3% of the ablation group and 65.5% in the control group (hazard ratio, 0.58 [95% CI, 0.35-0.96]; P=0.04). The observed difference was driven by a reduction in VT recurrence in the ablation arm (hazard ratio, 0.51 [95%CI, 0.29-0.90]; P=0.02). A statistically significant reduction in both ICD shocks (10.0% versus 24.6%; P=0.03) and antitachycardia pacing (16.2% versus 32.8%; P=0.04) was observed in patients who underwent ablation compared with control. No differences in cardiovascular hospitalization (32.0% versus. 33.7%; hazard ratio, 0.82 [95% CI, 0.43-1.56]; P=0.55) or mortality (8.9% versus 8.8%; hazard ratio, 1.40 [95% CI, 0.38-5.22]; P=0.62]) were observed. Ablation-related complications occurred in 8.3% of patients. CONCLUSIONS: Among patients with cardiomyopathy of varied causes, early catheter ablation performed at the time of ICD implantation significantly reduced the composite primary outcome of VT recurrence, cardiovascular hospitalization, or death. These findings were driven by a reduction in ICD therapies. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02848781.

Comparison of strategies for catheter ablation of left posterior fascicular ventricular tachycardia.

AIMS: Traditional ablation strategies including targeting the earliest Purkinje potential (PP) during left posterior fascicular (LPF) ventricular tachycardia (VT) or linear ablation at the middle segment of LPF during sinus rhythm are commonly used for the treatment of LPF-VT. Catheter ablation for LPF-VT targeting fragmented antegrade Purkinje (FAP) potential during sinus rhythm is a novel approach. We aimed to compare safety and efficacy of different ablation strategies (FAP ablation vs. traditional ablation) for the treatment of LPF-VT. METHODS AND RESULTS: Consecutive patients with electrocardiographically documented LPF-VT referred for catheter ablation received either FAP ablation approach or traditional ablation approach. Electrophysiological characteristics, procedural complications, and long-term clinical outcome were assessed. A total of 189 consecutive patients who underwent catheter ablation for LPF-VT were included. Fragmented antegrade Purkinje ablation was attempted in 95 patients, and traditional ablation was attempted in 94 patients. Acute ablation success with elimination of LPF-VT was achieved in all patients. Left posterior fascicular block occurred in 11 of 95 (11.6%) patients in the FAP group compared with 75 of 94 (79.8%) patients in the traditional group (P < 0.001). Fragmented antegrade Purkinje ablation was associated with significant shorter procedure time (94 ± 26 vs. 117 ± 23 min, P = 0.03) and fewer radiofrequency energy applications (4.1 ± 2.4 vs. 6.3 ± 3.5, P = 0.003) compared with the traditional group. One complete atrioventricular block and one left bundle branch block were seen in the traditional group. Over mean follow-up of 65 months, 89 (93.7%) patients in the FAP group and 81 (86.2%) patients in the traditional group remained free of recurrent VT off antiarrhythmic drugs (P = 0.157). CONCLUSION: Left posterior fascicular-ventricular tachycardia ablation utilizing FAP and traditional ablation approaches resulted in similar acute and long-term procedural outcomes. Serious His-Purkinje injury did occur infrequently during traditional ablation. The use of FAP ablation approach was associated with shorter procedure time and fewer radiofrequency energy applications, especially for non-inducible patients.

Electrophysiological characteristics and long-term outcome of substrate-based catheter ablation for left posterior fascicular ventricular tachycardia targeting fragmented antegrade Purkinje potentials during sinus rhythm.

AIMS: The aim of this study was to investigate the electrophysiological characteristics and long-term outcome of patients undergoing substrate-based ablation of left posterior fascicular ventricular tachycardia (LPF-VT) guided by targeting of fragmented antegrade Purkinje potentials (FAPs) during sinus rhythm. METHODS AND RESULTS: This study retrospectively analysed 50 consecutive patients referred for ablation. Substrate mapping during sinus rhythm was performed to identify the FAP that was targeted by ablation. FAPs were recorded in 48 of 50 (96%) patients during sinus rhythm. The distribution of FAPs was located at the proximal segment of posterior septal left ventricle (LV) in two (4.2%) patients, middle segment in 33 (68.8%) patients, and distal segment in 13 (27.1%) patients. In 32 of 48 (66.7%) patients, the FAP displayed a continuous multicomponent fragmented electrogram, while a fragmented, split, and uncoupled electrogram was recorded in 16 (33.3%) patients. Entrainment attempts at FAP region were performed successfully in seven patients, demonstrating concealed fusion and the critical isthmus of LPF-VT. Catheter ablation targeting at the FAPs successfully terminated the LPF-VT in all 48 patients in whom they were seen. Left posterior fascicular (LPF) block occurred in four (8%) patients after ablation. During a median follow-up period of 61.2 ± 16.8 months, 47 of 50 (94%) patients remained free from recurrent LPF-VT. CONCLUSION: Ablation of LPF-VT targeting FAP during sinus rhythm results in excellent long-term clinical outcome. FAPs were commonly located at the middle segment of posterior septal LV. Region with FAPs during sinus rhythm was predictive of critical site for re-entry.

A Frequent Observation of Wolff-Parkinson-White Syndrome and Fasciculoventricular Pathways in Patients With Danon Disease.

BACKGROUND: Danon disease is typically associated with cardiomyopathy and ventricular pre-excitation. The study aimed to characterize the clinical profile of Danon disease, analyze electrocardiographic (ECG) and electrophysiologic features, and investigate their association with Wolff-Parkinson-White (WPW) syndrome and fasciculoventricular pathways (FVPs).Methods and Results:Clinical course, family history, ECG and electrophysiological data were collected from 16 patients with Danon disease. Over 0.4-8 years of follow up, 1 female patient died suddenly, and 5 male patients died of progressive heart failure by age 13-20 years. Family history analysis revealed that 3 mothers experienced hospitalization or death for heart failure at age 28-41 years. There was 100% penetrance for ECG abnormalities in 13 patients with original ECGs. Short PR intervals and delta waves were present in 9 and 8 patients, respectively. There were significant age-associated increases in the QRS complex width (r=0.556, P=0.048) and the number of leads with notched QRS (r=0.575, P=0.04). Four patients who underwent electrophysiological studies all had FVPs, and 2 of them still had left-side atrioventricular pathways. CONCLUSIONS: Danon disease causes a malignant clinical course characterized by early death caused by heart failure in both genders and progressive ECG changes as patients age. The pre-excited ECG pattern is related to FVPs and WPW, which is suggestive of extensive cardiac involvement.

Prevalence of congenital heart disease among school children in Qinghai Province.

OBJECTIVES: This study aimed to investigate the prevalence of congenital heart disease (CHD) among school children in Qinghai province, a high-altitude region in China. METHODS: A cross-sectional study was conducted among school-aged children in 2019. All subjects completed a survey with a structure questionnaire and underwent CHD screening. CHD was screened by standard physical examination and further confirmed by echocardiography. Multivariate logistic regression were used to estimate the association of CHD prevalence with gender, nationality, and altitude. RESULTS: A total of 43,562 children aged 3-19 years participated in the study. The mean (SD) age was 11.2 (3.3) years. 49.7% were boys, and 80.0% were of Tibetan. CHD was identified in 293 children, with an overall prevalence of 6.73 ‰. Among them, 239 were unrecognized CHD, yielding a prevalence of 5.49 ‰. Atrial septal defect accounted for 51.9% of the CHD, followed by patent ductus arteriosus (31.1%), ventricular septal defect (9.9%). The CHD prevalence was significantly higher in female (8 ‰), Han race (18 ‰), children lived in Qumalai county (13 ‰), and children lived in a higher altitude (13 ‰). Female had greater prevalence of total CHD, atrial septal defect, and patent ductus arteriosus, but insignificant difference was observed in ventricular septal defect prvalence than male. In multivariable logistic regression analyses, female (OR, 1.48; 95% CI, 1.17-1.87, P = 0.001), Han population (OR, 3.28; 95% CI, 1.67-6.42, P = 0.001), and higher altitudes (OR, 2.28; 95% CI, 1.74-3.00, P < 0.001) were shown to be independently association with CHD prevalence. CONCLUSIONS: The prevalence of CHD in Qinghai province was 6.73 ‰. Altitude elevation, female, and Han population were independently association with CHD prevalence.

Targeted Ablation of Ventricular Tachycardia Guided by Wavefront Discontinuities During Sinus Rhythm: A New Functional Substrate Mapping Strategy.

BACKGROUND: Accurate and expedited identification of scar regions most prone to reentry is needed to guide ventricular tachycardia (VT) ablation. We aimed to prospectively assess outcomes of VT ablation guided primarily by the targeting of deceleration zones (DZ) identified by propagational analysis of ventricular activation during sinus rhythm. METHODS: Patients with scar-related VT were prospectively enrolled in the University of Chicago VT Ablation Registry between 2016 and 2018. Isochronal late activation maps annotated to the latest local electrogram deflection were created with high-density multielectrode mapping catheters. Targeted ablation of DZ (>3 isochrones within 1cm radius) was performed, prioritizing later activated regions with maximal isochronal crowding. When possible, activation mapping of VT was performed, and successful ablation sites were compared with DZ locations for mechanistic correlation. Patients were prospectively followed for VT recurrence and mortality. RESULTS: One hundred twenty patients (median age 65 years [59-71], 15% female, 50% nonischemic, median ejection fraction 31%) underwent 144 ablation procedures for scar-related VT. 57% of patients had previous ablation and epicardial access was employed in 59% of cases. High-density mapping during baseline rhythm was performed (2518 points [1615-3752] endocardial, 5049±2580 points epicardial) and identified an average of 2±1 DZ, which colocalized to successful termination sites in 95% of cases. The median total radiofrequency application duration was 29 min (21-38 min) to target DZ, representing ablation of 18% of the low-voltage area. At 12±10 months, 70% freedom from VT recurrence (80% in ischemic cardiomyopathy and 63% in nonischemic cardiomyopathy) was achieved. The overall survival rate was 87%. CONCLUSIONS: A novel voltage-independent high-density mapping display can identify the functional substrate for VT during sinus rhythm and guide targeted ablation, obviating the need for extensive radiofrequency delivery. Regions with isochronal crowding during the baseline rhythm were predictive of VT termination sites, providing mechanistic evidence that deceleration zones are highly arrhythmogenic, functioning as niduses for reentry.

Inability to capture with increasing current strength: Is this near-field or far-field?

We present a case of wide-complex tachycardia in which the clinical electrophysiological diagnosis was considered to be bundle branch re-entry ventricular tachycardia. A series of ventricular entrainment attempts were performed from the left and right ventricular septum to confirm the diagnosis. Entrainment pacing with a general current output (10 mA) was performed from the right ventricular septum with manifest fusion and a post-pacing interval similar to tachycardia cycle length. Thereafter, another entrainment attempt with a greater current output (20 mA) was performed from the same site. Paradoxically, concealed fusion was demonstrated by selective RB capture only, though there was no clear "RB" potential seen. In this case, we attempt to explain and illustrate the mechanism of paradoxical near-field inability to capture with increasing current strength.

Novel Strategy for Predicting Conduction Abnormalities During Transcatheter Closure of Perimembranous Ventricular Septal Defect in Adults.

BACKGROUND: In this study we evaluated the feasibility and efficacy of predicting conduction system abnormalities under 3-dimensional (3D) electroanatomic mapping guidance during transcatheter closure of perimembranous ventricular septal defects (pmVSDs) in adults.Methods and Results:The distribution of the His-Purkinje system (HPS) close to the margins of pmVSDs in the left ventricle was identified using 3D electroanatomic mapping and near-field HPS was further confirmed by different pacing protocols. Of the 20 patients in the study, 17 (85%) were successfully treated by transcatheter intervention. The minimum distance between the margins of the pmVSD and near-field HPS, as measured by 3D electroanatomic mapping, ranged from 1.3 to 3.9 mm (mean [± SD] 2.5±0.7 mm). Five patients with a minimum distance <2 mm had a higher risk (3/5; 60%) for adverse arrhythmic events, whereas patients with a distance >2 mm were at a much lower risk (1/15; 6.7%) of procedure-related conduction block (P=0.032). No other adverse events were recorded during the follow-up period (median 30 months). CONCLUSIONS: A minimum distance between the pmVSD and near-field HPS <2 mm was associated with a relatively high risk of closure-related conduction block. 3D electroanatomic mapping may be helpful in guiding decision making for transcatheter closure and reduce the incidence of adverse arrhythmic events.

Genetic Variants on SCN5A, KCNQ1, and KCNH2 in Patients with Ventricular Arrhythmias during Acute Myocardial Infarction in a Chinese Population.

OBJECTIVE: Acute myocardial infarction (AMI) remains a leading cause of morbidity and mortality worldwide. About half of sudden deaths from AMI are mainly because of malignant ventricular arrhythmias (VA) after AMI. The sodium channel gene SCN5A and potassium channel genes KCNQ1 and KCNH2 have been widely reported to be genetic risk factors for arrhythmia including Brugada syndrome and long QT syndrome (LQTS). A few studies reported the association of SCN5A variant with ventricular tachycardia (VT)/ventricular fibrillation (VF) complicating AMI. However, little is known about the role of KCNQ1 and KCNH2 in AMI with VA (AMI_VA). This study focuses on investigating the potential variants on SCN5A, KCNQ1, and KCNH2 contributing to AMI with VA in a Chinese population. MATERIALS AND METHODS: In total, 139 patients with AMI_VA, and 337 patients with AMI only, were included. Thirty exonic sites were selected to be screened. Sanger sequencing was used to detect variants. A subsequent association study was also performed between AMI_VA and AMI. RESULTS: Twelve variants [5 on KCNH2(NM_000238.3), 3 on KCNQ1(NM_000218.2), and 4 on SCN5A(NM_198056.2)] were identified in AMI_VA patients. Only 5 (KCNH2: c.2690A>C; KCNQ1: c.1927G>A, c.1343delC; SCN5A: c.1673A>G, c.3578G>A) of them are missense variants. Two (KCNQ1: c.1343delC and SCN5A: c.3578G>A) of the missense variants were predicted to be clinically pathogenic. All these variants were further genotyped in an AMI without VA group. The association study identified a statistically significant difference in genotype frequency of KCNH2: c.1539C>T and KCNH2: c.1467C>T between the AMI and AMI_VA groups. Moreover, 2 rare variants (KCNQ1: c.1944C>T and SCN5A: c.3621C>T) showed an elevated allelic frequency (more than 1.5-fold) in the AMI_VA group when compared to the AMI group. CONCLUSION: Twelve variants (predicting from benign/VUS to pathogenic) were identified on KCNH2, KCNQ1, and SCN5A in patients with AMI_VA. Genotype frequency comparison between AMI_VA and AMI identified 2 significant common variants on KCNH2. Meanwhile, the allelic frequency of 2 rare variants on KCNQ1 and SCN5A, respectively, were identified to be enriched in AMI_VA, although there was no statistical significance. The present study suggests that the ion-channel genes KCNH2, KCNQ1, and SCN5A may contribute to the pathogenesis of VA during AMI.

Invasive therapies for patients with concomitant heart failure and atrial fibrillation.

Atrial fibrillation (AF) and heart failure (HF) are two clinical entities that can present either separately or concurrently. One entity can lead to the other and vice versa as AF can not only be the underlying etiology of HF but also exacerbate HF due to other cardiac diseases. Besides prevention of cerebral and systemic embolism and elimination of AF-related symptoms, restoration of sinus rhythm for AF patients helps to avoid or reduce HF, irrespective of their underlying heart disease. Successful rates of medical therapy for AF are low in persistent AF, and much lower in long-standing AF, while invasive procedures for AF yield promising results. In this review, the authors evaluate the value of invasive therapies for HF patients complicated with non-valvular AF. We examine this clinical problem by interpreting the relationships between these two entities: the mechanism of tachycardia-induced cardiomyopathy (TIC), past opinions about rhythm control and rate control of AF, discrimination of HF-related AF and AF-induced HF, how to identify the AF patients that could benefit from invasive therapies, and how to select invasive therapies for different AF patients and peri-operative treatments.

Predictors, treatment, and long-term outcomes of coronary perforation during retrograde percutaneous coronary intervention via epicardial collaterals for recanalization of chronic coronary total occlusion.

OBJECTIVE: To investigate predictors, treatment, and long-term outcomes associated with coronary perforation (CP) in patients who underwent retrograde percutaneous coronary intervention (PCI) through epicardial collaterals for chronic total occlusion (CTO). BACKGROUND: Data regarding CP during retrograde PCI through epicardial collaterals for CTO are scarce. METHODS: We included 155 patients who underwent retrograde CTO PCI through epicardial collaterals at Guangdong Cardiovascular Institute from August 2011 to December 2017. The median follow-up was 2.5 years. Major adverse cardiac events (MACEs) were analyzed using the Kaplan-Meier method, and independent predictors of long-term MACE were determined using a multivariable Cox model. RESULTS: CP occurred in 24 (15.5%) patients, with the frequency of Ellis classes 1 or 2 and 3 being 41.7% and 58.3%, respectively. Seven (4.5%) patients had tamponade, which was effectively managed using coil embolization and pericardiocentesis. Renal dysfunction (odds ratio [OR]: 5.27; 95% confidence interval [CI]: 1.47-18.88; P = 0.011), right coronary artery (RCA) CTO (OR: 4.34; 95% CI: 1.29-14.63; P = 0.018), and Epi-CTO score ≥ 2 (OR: 3.27; 95% CI: 1.12-9.58; P = 0.030) were independent predictors of CP. At the 7-year follow-up, 17 patients had MACE. Multivariable analysis revealed that CP was not associated with worse long-term clinical outcomes (hazard ratio: 1.55; 95% CI: 0.45-5.32, P = 0.484). CONCLUSIONS: Retrograde CTO PCI through epicardial collaterals is at increased risk of CP, which is associated with renal dysfunction, RCA CTO, and Epi-CTO score ≥ 2. Prompt and proper management of CP is important. CP is not significantly associated with adverse clinical outcomes.

Transvenous dual-chamber pacemaker implantation in patients with persistent left superior vena cava.

BACKGROUND: Persistent left superior vena cava (PLSVC) is a rare congenital vascular anomaly. Permanent pacemaker implantation (PPI) in patients with PLSVC can be challenging because of the venous anomalies. We reported a case series of patients with PLSVC who underwent PPI with double active fixation leads. METHODS: From January 2012 to July 2016, 9 patients (three male and six females, mean age 68 ± 11 years) with PLSVC who received a dual-chamber pacemaker with double active fixation leads were enrolled retrospectively in this observational study. The indications for pacemaker implantation were symptomatic third-degree atrioventricular block in one and sick sinus syndrome in eight patients. RESULTS: PPI were implanted successfully in all 9 patients. Successful positioning of the ventricular leads at the right ventricular outflow tract (RVOT) septum with a "C" shaped stylet was achieved in 7 patients (77.8%). In the remaining two cases, the ventricular leads were placed in the right ventricular apex and the inferior free wall of the sub-tricuspid annulus. The atrial leads were placed at the lateral wall of the right atrium in all patients. Procedure time and fluoroscopy time were 85.3 ± 11.3 min and 4.5 ± 1.1 min respectively. During a mean follow-up of 4 years, no complications were observed and pacing parameters did not change significantly. CONCLUSION: PPI through PLSVC may be technically feasible, safe, and effective. Double active fixation leads may be standard for patients with PLSVC and most of the ventricular leads could be placed at the RVOT septum.

Unique electrocardiographic pattern "w" wave in lead I of idiopathic ventricular arrhythmias arising from the distal great cardiac vein.

BACKGROUND: The ECG characteristics of the distal coronary venous system ventricular arrhythmias (VAs) share common features with VAs arising from the aortic cusps or the endocardial left ventricular outflow tract (LVOT) beneath the cusps. The purpose of this study was to identify specific electrocardiographic and electrophysiological characteristics of VAs originating from the distal great cardiac vein (GCV). METHODS: Based on the successful ablation site, patients with idiopathic VAs from the distal GCV, left coronary cusp (LCC) or the subvalvular left ventricular outflow tract (LVOT) area were included in the present study. RESULTS: The final population consisted of 39 patients (35 males, mean age 51 ± 23 years). All VAs displayed a right bundle branch block (RBBB) morphology with inferior axis. Among these patients, 15 were successfully ablated at the GCV, 15 at the LCC and 9 at the subvalvular region. A "w" pattern in lead I was present in 12 out of 15 (80%) VAs originating from the distal GCV compared to none of VAs arising from the other two sites (p < 0.01). VAs with a GCV origin exhibited more commonly increased intrinsicoid deflection time, higher maximum deflection index and wider QRS duration compared to LCC and subvalvular sites (p < 0.05). Acceptable pace mapping at the successful ablation site was achieved in 10 patients. After an average of 36 ± 24 months follow up, 14 (93.3%) patients were free from VAs recurrence. CONCLUSION: A "w" pattern in lead I may distinguish distal GCV VAs from VAs arising from the LCC or the subvalvular region.

Association between elevated blood glucose level and non-valvular atrial fibrillation: a report from the Guangzhou heart study.

BACKGROUND: To estimate the prevalence of elevated blood glucose level (EBG, including type 2 diabetes mellitus and impaired fasting glucose), and its association with non-valvular atrial fibrillation (NVAF) in Guangzhou, China. METHODS: The population-based follow-up Guangzhou Heart Study collected baseline data from July 2015 to August 2017 among 12,013 permanent residents aged > 35 from 4 Guangzhou districts. Two streets (Dadong and Baiyun) in the Yuexiu District, and one street (Xiaoguwei) and two towns (Xinzao and Nancun) in the Panyu District were chosen as representative of urban and rural areas, respectively. Each participant completed a comprehensive questionnaire, and underwent physical examination, blood sample collection for laboratory testing, electrocardiography, and other evaluations. Multivariable logistic regression analyses were used to estimate the independent association between hyperglycemia and NVAF prevalence. RESULTS: The prevalence of EBG in overall study population was 29.9%. Compared with residents without EBG, the odds ratio (OR) for AF among residents with EBG was significantly higher (1.94, 95% confidence interval [CI]: 1.40-2.70, P <  0.001), even after multivariate adjustment for metabolic abnormalities (OR = 1.60, 95% CI: 1.14-2.25, P = 0.007), and driven by women (OR = 1.80, 95% CI: 1.12-2.91, P = 0.016). CONCLUSIONS: In Guangzhou, China, prevalence of EBG is high among residents aged > 35 years and associated with a multivariate adjusted increase in prevalence of NVAF overall and in women.

Mid-term outcomes of concomitant left atrial appendage closure and catheter ablation for non-valvular atrial fibrillation: a multicenter registry.

To investigate the safety and midterm outcome of concomitant left atrial appendage (LAA) closure and catheter ablation (CA) as a one-stage hybrid procedure for non-valvular atrial fibrillation (AF) in a multicenter registry. A total of 50 consecutive patients with symptomatic drug-resistant non-valvular AF with CHA2DS2-VASc score ≥ 2 and contraindications for antithrombotic therapy were included in the prospectively established LAA closure registry, and underwent concomitant LAA closure (48 for WATCHMAN and 2 for ACP) and CA procedure (40 for radiofrequency and 10 for cryoballoon CA). Two cardiac tamponades, one peripheral vascular complications and one mild air embolism were observed during perioperative period. After mean follow-up of 20.2 ± 11.5 months, 18 (36%) patients presented with atrial arrhythmia relapse and 45 (91.8%) patients presented with complete sealing; furthermore, there were two transient ischemic attacks and one ischemic stroke under an off-oral anticoagulant situation, respectively. Concomitant CA and LAA closure as a one-stage hybrid procedure might be feasible and potentially decrease costs in patients with symptomatic non-valvular AF with high stroke risk and contraindication to antithrombotic treatment, and as safe as LAA closure procedure only during the perioperative period. However, it was necessary to further validate the mid-term safety.

Characteristics, Mechanism and Long-Term Ablation Outcome of Atrial Tachycardias After Mitral Valvular Surgery and Concomitant Cox-MAZE IV Procedure.

The incidence of atrial tachycardia (AT) after rheumatic mitral valvular (RMV) surgery has been well described. However, there have been few reports on the characteristics, mechanism, and long-term ablation outcome of ATs after RMV surgery and concomitant Cox-MAZE IV procedure.The present study reviewed consecutive patients who underwent AT ablation between May 2008 and July 2013. All patients were refractory to antiarrhythmic drugs (AADs) and had a history of RMV surgery and Cox-MAZE IV procedure. A total of 34 patients underwent AT ablation after RMV surgery and concomitant Cox-MAZE IV procedure, and presented 57 mappable and 2 unmappable ATs. The 57 mappable ATs included 14 focal-ATs and 43 reentry-ATs. Ten of the 14 focal-like ATs were located at the pulmonary vein (PV) antrum and border of a box lesion. Of the 43 reentry-ATs, 16 were marco-reentrant around the mitral annulus (MA) and 16 around the tricuspid annulus. There were 41 atypical ATs (non-cavotricuspid isthmus related) including 16 ATs related to the box lesion and 21 ATs related to other Cox-MAZE IV lesions. The AT were successfully terminated in 33 (97.1%) patients. After mean follow-up of 46.9 ± 15.7 months, 25 (73.5%) patients maintained sinus rhythm without AADs after a single procedure and 28 (82.4%) patients after repeated procedures.The recurrent ATs after RMV surgery and concomitant Cox-MAZE IV were mainly reentry mechanism, and largely related to LA. An incomplete lesion or re-conductive gaps in a prior lesion might be the predominant mechanisms for these ATs. Catheter-based mapping and ablation of these ATs seems to be effective and safe during a long-term follow-up.

Case report of familial sudden cardiac death caused by a DSG2 p.F531C mutation as genetic background when carrying with heterozygous KCNE5 p.D92E/E93X mutation.

BACKGROUND: Sudden cardiac death (SCD) induced by malignant ventricular tachycardia (MVT) among young adults with right ventricular cardiomyopathy/dysplasia (ARVC/D) is a devastating event. Parts of ARVC/D patients have a mutation in genes encoding components of cardiac desmosomes, such as desmoglein-2 (DSG2), plakophilin-2 and desmoplakin. CASE PRESENTATION: Here we report a potentially pathogenic mutation in the DSG2 gene, which was identified in a family with ARVC/D using Whole Exome Sequencing (WES) and Sanger Sequencing. In all, Patient III:1 with ARVC/D carried the compound heterozygous mutations of DSG2 p.F531C and KCNE5 p.D92E/E93X, which were both inherited from her mother (II:2), who died of SCD. Carriers of DSG2p.F531C showed various phenotypes, such as ARVC/D, SCD, MVT and dilated cardiomyopathy. For III:1, there were significant low-voltage regions in the inferior-apical, inferior-lateral wall of the right ventricular epicardium and outflow tracts of the right ventricle. Under the guidance of a three-dimensional mapping system, MVT was successfully ablated with an epicardial-endocardial approach targeting for late, double or fragmental potentials after implantable cardioverter-defibrillator (ICD) electrical storms. No VT recurrence was observed during the one year of follow-up. CONCLUSIONS: When coexisting with heterozygous KCNE5 p.D92E/E93X, heterozygous DSG2 p.F531C as a genetic background was found to predispose to ARVC/D, SCD and MVT, which were successfully ablated using an epicardial-endocardial approach.