Arrhythmias and Clinical Outcomes in a Swiss Multicenter Cohort of Patients With Dextro-Transposition of the Great Arteries and Atrial Switch

Background Data on the incidence of arrhythmias, associated cardiac interventions, and outcome in patients with dextro-transposition of the great arteries and atrial switch are scarce. Methods and Results In this multicenter analysis, we included adult patients with dextro-transposition of the great arteries and atrial switch regularly followed up at 3 Swiss tertiary care hospitals. The primary outcome was a composite of left ventricular assist device, heart transplantation, and death. The secondary outcome was occurrence of ventricular tachycardia, ventricular fibrillation, or sudden cardiac death. We identified 207 patients (34% women; median age at last follow-up, 35 years) with dextro-transposition of the great arteries and atrial switch. Arrhythmias occurred in 97 patients (47%) at a median age of 22 years. A pacemaker or an implantable cardioverter-defibrillator was implanted in 39 (19%) and 13 (6%) patients, respectively, and 33 (16%) patients underwent a total of 51 ablation procedures to target 60 intra-atrial re-entry tachycardias, 4 atrioventricular nodal re-entry tachycardias, and 1 atrial fibrillation. The primary outcome occurred in 21 patients (10%), and the secondary outcome occurred in 18 patients (9%); both were more common in patients with concomitant ventricular septum defect than in those without (hazard ratio [HR], 3.06 [95% CI, 1.29-7.27], P=0.011; and HR, 3.62 [95% CI, 1.43-9.18], P=0.007, respectively). Conclusions In patients with dextro-transposition of the great arteries and atrial switch reaching adulthood, arrhythmias occur in almost half of patients, and associated rhythm interventions are frequent. One-tenth of those patients do not survive until the age of 35 years free from left ventricular assist device or heart transplantation, and the outcome is worse in patients with concomitant ventricular septum defect

Differences in Atrial Remodeling in Hypertrophic Cardiomyopathy Compared to Hypertensive Heart Disease and Athletes’ Hearts.

BACKGROUND: Hypertrophic cardiomyopathy (HCM), hypertensive heart disease (HHD) and athletes' heart share an increased prevalence of atrial fibrillation. Atrial cardiomyopathy in these patients may have different characteristics and help to distinguish these conditions. METHODS: In this single-center study, we prospectively collected and analyzed electrocardiographic (12-lead ECG, signal-averaged ECG (SAECG), 24 h Holter ECG) and echocardiographic data in patients with HCM and HHD and in endurance athletes. Patients with atrial fibrillation were excluded. RESULTS: We compared data of 27 patients with HCM (70% males, mean age 50 +/- 14 years), 324 patients with HHD (52% males, mean age 75 +/- 5.5 years), and 215 endurance athletes (72% males, mean age 42 +/- 7.5 years). HCM patients had significantly longer filtered P-wave duration (153 +/- 26 ms) and PR interval (191 +/- 48 ms) compared to HHD patients (144 +/- 16 ms, p = 0.012 and 178 +/- 31, p = 0.034, respectively) and athletes (134 +/- 14 ms, p = 0.001 and 165 +/- 26 ms, both p &lt; 0.001, respectively). HCM patients had a mean of 4.9 +/- 16 premature atrial complexes per hour. Premature atrial complexes per hour were significantly more frequent in HHD patients (27 +/- 86, p &lt; 0.001), but not in athletes (2.7 +/- 23, p = 0.639). Left atrial volume index (LAVI) was 43 +/- 14 mL/m(2) in HCM patients and significantly larger than age- and sex-corrected LAVI in HHD patients 30 +/- 10 mL/m(2); p &lt; 0.001) and athletes (31 +/- 9.5 mL/m(2); p &lt; 0.001). A borderline interventricular septum thickness >/=13 mm and </=15 mm was found in 114 (35%) HHD patients, 12 (6%) athletes and 3 (11%) HCM patients. CONCLUSIONS: Structural and electrical atrial remodeling is more advanced in HCM patients compared to HHD patients and athletes

Assessment of New Onset Arrhythmias After Transcatheter Aortic Valve Implantation Using an Implantable Cardiac Monitor.

Background Transcatheter aortic valve implantation (TAVI) is associated with new onset brady- and tachyarrhythmias which may impact clinical outcome. Aims To investigate the true incidence of new onset arrhythmias within 12 months after TAVI using an implantable cardiac monitor (ICM). Methods One hundred patients undergoing TAVI received an ICM within 3 months before or up to 5 days after TAVI. Patients were followed-up for 12 months after discharge from TAVI for the occurrence of atrial fibrillation (AF), bradycardia (≤30 bpm), advanced atrioventricular (AV) block, sustained ventricular and supraventricular tachycardia. Results A previously undiagnosed arrhythmia was observed in 31 patients (31%) and comprised AF in 19 patients (19%), advanced AV block in 3 patients (3%), and sustained supraventricular and ventricular tachycardia in 10 (10%) and 2 patients (2%), respectively. Three patients had a clinical diagnosis of sick-sinus-syndrome. A permanent pacemaker (PPM) was implanted in six patients (6%). The prevalence of pre-existing AF was 28%, and 47% of the patients had AF at the end of the study period. AF burden was significantly higher in patients with pre-existing [26.7% (IQR 0.3%; 100%)] compared to patients with new-onset AF [0.0% (IQR 0.0%; 0.06%); p = 0.001]. Three patients died after TAVI without evidence of an arrhythmic cause according to the available ICM recordings. Conclusions Rhythm monitoring for 12 months after TAVI revealed new arrhythmias, mainly AF, in almost one third of patients. Atrial fibrillation burden was higher in patients with prevalent compared to incident AF. Selected patients may benefit from short-term remote monitoring. Trial Registration https://clinicaltrials.gov/: NCT02559011

Incidental Arrhythmias During Atrial Fibrillation Screening With Repeat 7-Day Holter ECGs in a Hospital-Based Patient Population.

BACKGROUND Screening for atrial fibrillation (AF) may reveal incidental arrhythmias of relevance. The aim of this study was to describe incidental arrhythmias detected during screening for AF in the STAR-FIB (Predicting SilenT AtRial FIBrillation in Patients at High Thrombembolic Risk) cohort study. METHODS AND RESULTS In the STAR-FIB cohort study, we screened hospitalized patients for AF with 3 repeat 7-day Holter ECGs. We analyzed all Holter ECGs for the presence of the following incidental arrhythmias: (1) sinus node dysfunction, defined as sinus pause of ≥3 seconds' duration; (2) second-degree (including Wenckebach) or higher-degree atrioventricular block (AVB); (3) sustained supraventricular tachycardia of ≥30 seconds' duration; and (4) sustained ventricular tachycardia of ≥30 seconds' duration. We furthermore report treatment decisions because of incidental arrhythmias. A total of 2077 Holter ECGs were performed in 794 patients (mean age, 74.7 years; 49% women), resulting in a mean cumulative duration of analyzable ECG signal of 414±136 hours/patient. We found incidental arrhythmias in 94 patients (11.8%). Among these were sinus node dysfunction in 14 patients (1.8%), AVB in 41 (5.2%), supraventricular tachycardia in 42 (5.3%), and ventricular tachycardia in 2 (0.3%). Second-degree AVB was found in 23 patients (2.9%), 2:1 AVB in 10 (1.3%), and complete AVB in 8 (1%). Subsequently, 8 patients underwent pacemaker implantation, 1 for sinus node dysfunction (post-AF conversion pause of 9 seconds) and 7 for advanced AVB. One patient had an implantable cardioverter-defibrillator implanted for syncopal ventricular tachycardia. CONCLUSIONS Incidental arrhythmias were frequently detected during screening for AF in the STAR-FIB study and resulted in device therapy in 1.1% of our cohort patients

Arrhythmias and Clinical Outcomes in a Swiss Multicenter Cohort of Patients With Dextro‐Transposition of the Great Arteries and Atrial Switch

Background Data on the incidence of arrhythmias, associated cardiac interventions, and outcome in patients with dextro‐transposition of the great arteries and atrial switch are scarce. Methods and Results In this multicenter analysis, we included adult patients with dextro‐transposition of the great arteries and atrial switch regularly followed up at 3 Swiss tertiary care hospitals. The primary outcome was a composite of left ventricular assist device, heart transplantation, and death. The secondary outcome was occurrence of ventricular tachycardia, ventricular fibrillation, or sudden cardiac death. We identified 207 patients (34% women; median age at last follow‐up, 35 years) with dextro‐transposition of the great arteries and atrial switch. Arrhythmias occurred in 97 patients (47%) at a median age of 22 years. A pacemaker or an implantable cardioverter‐defibrillator was implanted in 39 (19%) and 13 (6%) patients, respectively, and 33 (16%) patients underwent a total of 51 ablation procedures to target 60 intra‐atrial re‐entry tachycardias, 4 atrioventricular nodal re‐entry tachycardias, and 1 atrial fibrillation. The primary outcome occurred in 21 patients (10%), and the secondary outcome occurred in 18 patients (9%); both were more common in patients with concomitant ventricular septum defect than in those without (hazard ratio [HR], 3.06 [95% CI, 1.29–7.27], P=0.011; and HR, 3.62 [95% CI, 1.43–9.18], P=0.007, respectively). Conclusions In patients with dextro‐transposition of the great arteries and atrial switch reaching adulthood, arrhythmias occur in almost half of patients, and associated rhythm interventions are frequent. One‐tenth of those patients do not survive until the age of 35 years free from left ventricular assist device or heart transplantation, and the outcome is worse in patients with concomitant ventricular septum defect

The SilenT AtRial FIBrillation (STAR-FIB) study programme - design and rationale.

AIMS OF THE STUDY Anticoagulation of patients with screen-detected atrial fibrillation may prevent ischaemic strokes. The STAR-FIB study programme aims to determine the age- and sex-specific prevalence of silent atrial fibrillation and to develop a clinical prediction model to identify patients at risk of undiagnosed atrial fibrillation in a hospitalised patient population. METHODS The STAR-FIB study programme includes a prospective cohort study and a case-control study of hospitalised patients aged 65&ndash;84 years, evenly distributed for both age and sex. We recruited 795 patients without atrial fibrillation for the cohort study (49.2% females; median age 74.8 years). All patients had three serial 7-day Holter ECGs to screen for silent atrial fibrillation. The primary endpoint will be any episode of atrial fibrillation or atrial flutter of &ge;30 seconds duration. The age- and sex-specific prevalence of newly diagnosed atrial fibrillation will be estimated. For the case-control study, 120 patients with paroxysmal atrial fibrillation were recruited as cases (41.7% females; median age 74.6 years); controls will be randomly selected from the cohort study in a 2:1 ratio. All participants in the cohort study and all cases were prospectively evaluated including clinical, laboratory, echocardiographic and electrical parameters. A clinical prediction model for undiagnosed atrial fibrillation will be derived in the case-control study and externally validated in the cohort study. CONCLUSIONS The STAR-FIB study programme will estimate the age- and sex-specific prevalence of silent atrial fibrillation in a hospitalised patient population, and develop and validate a clinical prediction model to identify patients at risk of silent atrial fibrillation

Age and Sex Specific Prevalence of Clinical and Screen-Detected Atrial Fibrillation in Hospitalized Patients.

BACKGROUND The prevalence of atrial fibrillation (AF) is high in older patients. The present study aimed to estimate the age and sex specific prevalence of clinical and screen-detected atrial fibrillation (AF) in hospitalized patients. METHODS The STAR-FIB cohort study was a prospective cohort study recruiting participants from a large source population of hospitalized patients aged 65-84 years. The estimated size of the source population was 26,035 (95% CI 25,918-26,152), and 795 consenting patients without clinical AF were included in the cohort study after stratification by sex and age (49.2% females; mean age 74.7 years). Patients in the cohort study underwent three seven-day Holter ECGs in intervals of two months to screen for AF. RESULTS In the source population, the estimated prevalence of clinical AF was 22.2% (95% CI 18.4-26.1), 23.8% for males (95% CI 20.9-26.6) and 19.8% for females (95% CI 17.3-22.4; p for difference between sexes, 0.004). There was a linear trend for an increase in the prevalence of clinical AF with increasing age, overall and in both sexes. In the cohort study, AF was newly diagnosed in 38 patients, for an estimated prevalence of screen-detected AF of 4.9% overall (95% CI 3.3-6.6), 5.5% in males (95% CI 3.2-7.8) and 4.0% in females (95% CI 2.0-6.0; p for difference between sexes, 0.041). The estimated prevalence of screen-detected AF in the source population was 3.8% overall, 4.2% in males and 3.2% in females. CONCLUSION In a large hospital-based patient population aged 65-84 years, the prevalence of clinical AF and of screen-detected AF was 22.2% and 3.8%, respectively, and significantly higher in males than females

Permanent Pacemaker Implantation Late after Transcatheter Aortic Valve Implantation.

BACKGROUND Impairment of atrioventricular (AV) conduction may occur late after transcatheter aortic valve implantation (TAVI) and progression to complete AV block is a matter of concern. OBJECTIVE To describe the incidence of permanent pacemaker (PPM) implantation late after TAVI. METHODS In a prospective TAVI registry, we retrospectively identified patients with PPM implantation after hospital discharge for TAVI and analyzed serial ECGs for AV conduction impairment prior to PPM implantation. RESULTS Among 1,059 patients discharged after TAVI without PPM between January 2012 and December 2017, 62 patients (5.9%) underwent PPM implantation at a median of 305 days after discharge for TAVI. Indications for PPM implantation late after TAVI were AV conduction impairment in 46 patients (74.2%), sick-sinus-syndrome in 10 (16.1%), cardiac resynchronization or implantable cardioverter/defibrillator indication in two (3.2%), and a pace & ablate strategy in four (6.5%). Clinical symptoms leading to PPM implantation late after TAVI included syncope in 19 patients (30.7%), pre-syncope in seven (11.3%), and dyspnea in eight (12.9%). First-degree AV block and new left bundle branch block (LBBB) after TAVI as well as valve-in-valve procedure during follow-up were independent predictors for PPM implantation late after TAVI due to AV conduction impairment. CONCLUSIONS PPM implantation late after TAVI is infrequent and associated with clinical symptoms in half of patients. Impairment of AV-conduction was the indication in three quarters of patients. First-degree AV block and new LBBB after TAVI as well as valve-in-valve procedure during follow-up emerged as independent predictors

Validation of the 2019 Expert Consensus Algorithm for the Management of Conduction Disturbances After TAVR.

OBJECTIVES The aim of this study was to validate the 2019 consensus algorithm in a large cohort of contemporary transcatheter aortic valve replacement (TAVR) patients. BACKGROUND The optimal management of patients with atrioventricular conduction disturbances after TAVR is unknown. Guidance was consolidated in an expert consensus algorithm in 2019. METHODS In a retrospective analysis of a prospective registry, patients were classified according to the 2019 consensus algorithm as eligible for early discharge (day 1 or 2 after TAVR), higher risk for high-degree atrioventricular block (HAVB) or complete heart block (CHB) or in need for a permanent pacemaker (PPM). The primary endpoint was the incidence of PPM implantation for HAVB or CHB within 30 days after TAVR. Patients with prior PPM or implantable cardioverter-defibrillator implantation, valve-in-valve procedures, or incomplete electrocardiographic data were excluded. RESULTS Among 1,439 patients undergoing TAVR between January 2014 and December 2019, the 2019 consensus algorithm classified 73% as eligible for early discharge, 21% as at higher risk for HAVB or CHB, and 6% as in need of PPM. PPM implantation for HAVB or CHB occurred in 234 patients (16%) within 30 days after TAVR. The incidence of PPM implantation was 2.7% in the early discharge group, 41% in the group with higher risk for HAVB or CHB, and 100% in the PPM group. CONCLUSIONS The 2019 consensus algorithm safely identifies patients with no need for PPM implantation. This strategy allows more uniform management of TAVR patients and facilitates early discharge of low-risk patients without prolonged monitoring in 3 of 4 patients. However, the algorithm is less precise in the identification of high-risk patients

Efficacy and safety of ethanol infusion into the vein of Marshall for mitral isthmus ablation.

INTRODUCTION Chemical ablation by retrograde infusion of ethanol into the vein of Marshall (VOM-EI) can facilitate the achievement of mitral isthmus block. This study sought to describe the efficacy and safety of this technique. METHODS AND RESULTS Twenty-two consecutive patients (14 males, median age 71 years) with attempted VOM-EI for mitral isthmus ablation were included in the study. VOM-EI was successfully performed with a median of 4 ml of 96% ethanol in 19 patients (86%) and the mitral isthmus was successfully blocked in all (100%). Touch up endocardial and/or epicardial ablation after VOM-EI was necessary for 12 patients (63%). Perimitral flutter was present in 12 patients (63%) during VOM-EI and terminated or slowed by VOM-EI in 4 and 3 patients, respectively. The low-voltage area of the mitral isthmus region increased from 3.1 cm2 (interquartile range [IQR] 0-7.9) before to 13.2 cm2 (IQR: 8.2-15.0) after VOM-EI and correlated significantly with the volume of ethanol injected (p = .03). Median high-sensitive cardiac troponin-T increased significantly from 330 ng/L (IQR: 221-516) the evening of the procedure to 598 ng/L (IQR: 382-769; p = .02) the following morning. A small pericardial effusion occurred in three patients (16%), mild pericarditis in one (5%), and uneventful VOM dissection in two (11%). After a median follow-up of 3.5 months (IQR: 3.0-11.0), 10 of 18 patients (56%) with VOM-EI and available follow-up had arrhythmia recurrence. Repeat ablation was performed in five patients (50%) and peri-mitral flutter diagnosed in three (60%). CONCLUSION VOM-EI is feasible, safe, and effective to achieve acute mitral isthmus block