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Background-The arrhythmia burden in tetralogy of Fallot, types of arrhythmias encountered, and risk profile may change as the population ages. Methods and Results-The

Background: Advanced generation ablation technologies have been developed to achieve more effective pulmonary vein isolation (PVI) and minimize arrhythmia recurrence after atrial fibrillation (AF) ablation. Methods: We randomly assigned 346 patients with drug-refractory paroxysmal AF to contact force–guided radiofrequency ablation (CF-RF; n=115), 4-minute cryoballoon ablation (Cryo-4; n=115), or 2-minute cryoballoon ablation (Cryo-2; n=116). Follow-up was 12 months. The primary outcome was time to first documented recurrence of symptomatic or asymptomatic atrial tachyarrhythmia (AF, atrial flutter, or atrial tachycardia) between days 91 and 365 after ablation or a repeat ablation procedure at any time. Secondary end points included freedom from symptomatic arrhythmia and AF burden. All patients received an implantable loop recorder. Results: One-year freedom from atrial tachyarrhythmia defined by continuous rhythm monitoring was 53.9%, 52.2%, and 51.7% with CF-RF, Cryo-4, and Cryo-2, respectively ( P =0.87). One-year freedom from symptomatic atrial tachyarrhythmia defined by continuous rhythm monitoring was 79.1%, 78.2%, and 73.3% with CF-RF, Cryo-4, and Cryo-2, respectively ( P =0.26). Compared with the monitoring period before ablation, AF burden was reduced by a median of 99.3% (interquartile range, 67.8%–100.0%) with CF-RF, 99.9% (interquartile range, 65.3%–100.0%) with Cryo-4, and 98.4% (interquartile range, 56.2%–100.0%) with Cryo-2 ( P =0.36). Serious adverse events occurred in 3 patients (2.6%) in the CF-RF group, 6 patients (5.3%) in the Cryo-4 group, and 7 patients (6.0%) in the Cryo-2 group, with no significant difference between groups ( P =0.24). The CF-RF group had a significantly longer procedure duration but significantly shorter fluoroscopy exposure ( P <0.001 vs cryoballoon groups). Conclusions: In this multicenter, randomized, single-blinded trial, CF-RF and 2 different regimens of cryoballoon ablation resulted in no difference in 1-year efficacy, which was 53% by time to first recurrence but >98% burden reduction as assessed by continuous cardiac rhythm monitoring. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01913522.

Background-Tetralogy of Fallot is the most common form of congenital heart disease in implantable cardioverterdefibrillator (ICD) recipients, yet little is known about the value of ICDs in this patient population. Methods and Results-We conducted a multicenter cohort study in high-risk patients with Tetralogy of Fallot to determine actuarial rates of ICD discharges, identify risk factors, and characterize ICD-related complications. A total of 121 patients (median age 33.3 years; 59.5% male) were enrolled from 11 sites and followed up for a median of 3.7 years. ICDs were implanted for primary prevention in 68 patients (56.2%) and for secondary prevention in 53 (43.8%), defined by clinical sustained ventricular tachyarrhythmia or resuscitated sudden death. Overall, 37 patients (30.6%) received at least 1 appropriate and effective ICD discharge, with a median ventricular tachyarrhythmia rate of 213 bpm. Annual actuarial rates of appropriate ICD shocks were 7.7% and 9.8% in primary and secondary prevention, respectively (Pϭ0.11). A higher left ventricular end-diastolic pressure (hazard ratio 1.3 per mm Hg, Pϭ0.004) and nonsustained ventricular tachycardia (hazard ratio 3.7, Pϭ0.023) independently predicted appropriate ICD shocks in primary prevention. Inappropriate shocks occurred in 5.8% of patients yearly. Additionally, 36 patients (29.8%) experienced complications, of which 6 (5.0%) were acute, 25 (20.7%) were late lead-related, and 7 (5.8%) were late generator-related complications. Nine patients died during follow-up, which corresponds to an actuarial annual mortality rate of 2.2%, which did not differ between the primary and secondary prevention groups. Conclusions-Patients with tetralogy of Fallot and ICDs for primary and secondary prevention experience high rates of appropriate and effective shocks; however, inappropriate shocks and late lead-related complications are common.

Background-Catheter ablation of ventricular tachycardia (VT) is effective and particularly useful in patients with frequent defibrillator interventions. Various substrate modification techniques have been described for unmappable or hemodynamically intolerable VT. Noninducibility is the most frequently used end point but is associated with significant limitations, so the optimal end point remains unclear. We hypothesized that elimination of local abnormal ventricular activities (LAVAs) during sinus rhythm or ventricular pacing would be a useful and effective end point for substrate-based VT ablation. As an adjunct to this strategy, we used a new high-density mapping catheter and frequently used epicardial mapping. Methods and Results-Seventy patients (age, 67Ϯ11 years; 7 female) with VT and structurally abnormal ventricle(s) were prospectively enrolled. Conventional mapping was performed in sinus rhythm in all, and a high-density Pentaray mapping catheter was used in the endocardium (nϭ35)

This large-scale, international study found that overall QOL in adults with CHD was generally good. Variation in QOL was related to patient characteristics but not country-specific characteristics. Hence, patients at risk for poorer QOL can be identified using uniform criteria. General principles for designing interventions to improve QOL can be developed.

Objective The goal of this project was to quantify the prevalence of gaps in cardiology care, identify predictors of gaps, and assess barriers to care among adult congenital heart disease (ACHD) patients. Background ACHD patients risk interruptions in care that are associated with undesired outcomes. Methods Patients (≥18years) with first presentation to an ACHD clinic completed a survey regarding gaps in, and barriers to, care. Results Among 12 ACHD centers, 922 subjects (54% female) were recruited. A >3 year gap in cardiology care was identified in 42%, with 8% having gaps longer than a decade. Mean age at first gap was 19.9 years. The majority of respondents had more than high school education, and knew their heart condition. Most common reasons for gaps included feeling well, unaware follow-up required, and complete absence from medical care. Disease complexity was predictive of gap in care with 59% of mild, 42% of moderate and 26% of severe disease subjects reporting gaps (p<0.0001). Clinic location significantly predicted gaps (p<0.0001) while gender, race, and education level did not. Common reasons for returning to care were new symptoms, referral from provider, and desire to prevent problems. Conclusions ACHD patients have gaps in cardiology care; the first lapse commonly occurred around 19 years, a time when transition to adult services is contemplated. Gaps were more common among subjects with mild and moderate diagnoses and at particular locations. These results provide a framework for developing strategies to decrease gaps and address barriers to care in the ACHD population.

Background-Pharmacological blockade of the renin-angiotensin system improves exercise tolerance in patients with left ventricular dysfunction, yet its impact on patients with systemic right ventricles (RVs) remains unknown. Methods and Results-A multicenter, randomized, double-blind, placebo-controlled, crossover clinical trial was performed to assess the effects of losartan on exercise capacity and neurohormonal levels in patients with systemic RVs. Of 29 patients studied (age, 30.3Ϯ10.9 years), 21 had transposition of the great arteries with a Mustard baffle, and 8 had congenitally corrected transposition of the great arteries. Baseline values were as follows: V O 2 max, 29.8Ϯ5.6 mL · kg Ϫ1 · min Ϫ1 (73.5Ϯ12.9% predicted value); RV ejection fraction, 41.6Ϯ9.3%; N-terminal pro brain natriuretic peptide (NT-proBNP), 257.7Ϯ243.4 pg/mL (normal Ͻ125 pg/mL); and angiotensin II, 5.7Ϯ4.9 pg/mL (normal Ͻ5.0 pg/mL). Comparing losartan to placebo showed no differences in V O 2 max (29.9Ϯ5.4 versus 29.4Ϯ6.2 mL · kg Ϫ1 · min Ϫ1 ; Pϭ0.43), exercise duration (632.3Ϯ123.0 versus 629.9Ϯ140.7 seconds; Pϭ0.76), and NT-proBNP levels (201.2Ϯ267.8 versus 229.7Ϯ291.5 pg/mL; Pϭ0.10), despite a trend toward increased angiotensin II levels (15.2Ϯ13.8 versus 8.8Ϯ12.5 pg/mL; Pϭ0.08). Conclusions-In adults with systemic RVs, losartan did not improve exercise capacity or reduce NT-proBNP levels.Minimal baseline activation of the renin-angiotensin system may explain this lack of benefit and imply an alternative pathophysiological mechanism for the progressive ventricular dysfunction and impaired exercise capacity observed in such patients. Key Words: angiotensin Ⅲ exercise Ⅲ transposition of great vessels P atients with congenitally corrected transposition of the great arteries (L-TGA) or intra-atrial baffle repair for complete transposition of the great arteries (D-TGA) function with a morphological right ventricle (RV) supporting a systemic circulation. Overall, excellent long-term survival is reported, with most young adults remaining symptom free. 1,2 However, long-term sequelae include progressive RV dilatation, systolic ventricular dysfunction, 2-5 impaired exercise tolerance, 6,7 arrhythmias, 1,2,5 and sudden death, 1 raising concern over the suboptimal capacity of the RV to endure against a systemic afterload.In both symptomatic and asymptomatic patients with left ventricular (LV) dysfunction, pharmacological blockade of the renin-angiotensin system (RAS) improves LV filling pressures, 8 -10 cardiac index, 8,9 exercise tolerance, 8 -12 and overall survival. [13][14][15] Results of such studies are often extrapolated to patients with systemic RVs, and therapy frequently is empirically initiated. However, beneficial effects of inhibiting the RAS in patients with systemic RVs have not yet been demonstrated. This study therefore was designed to assess the effects of losartan on exercise capacity and neurohormonal levels in adults with systemic RVs. Methods Study PopulationThe study population was derived from patients having L-TGA or ...