BackgroundAtrial flutter-related tachycardiomyopathy (AFL-TCM) is a rare and treatable cause of heart failure. Little is known about its epidemiology and long-term prognosis. Our aims are to determine the prevalence, predictors and outcomes of AFL-TCM. Methods and resultsA total of 1269 patients were referred for radiofrequency ablation of AFL between January 1996 and September 2014; 184 had reduced left ventricular ejection fraction (LVEF <40%). At 6 months after AFL ablation, 103 patients (8.1% of the population, 56% of patients with baseline LVEF <40%) had marked LVEF improvement: these were considered to have AFL-TCM. Patients with persisting reduced LVEF were considered to have systolic dysfunction unrelated to AFL. Patients were followed for a median (percentile 25-75 ) of 1.15 (0.4-2.8) years. Patients with AFL-TCM were younger, had lower prevalence of ischaemic cardiomyopathy and used less antiarrhythmic drugs than patients with systolic dysfunction unrelated to AFL. In multivariable analysis, ischemic cardiomyopathy [odds ratio (OR) = 0.32, 95% confidence interval (CI) 0.15-0.68) P = 0.003] and prescription of antiarrhythmic drug before ablation [OR = 0.41, 95% CI 0.20-0.84, P = 0.02] were significantly associated with a lower probability of LVEF improvement during follow-up. Patients with AFL-TCM had similar survival to patients without systolic dysfunction at baseline [hazard ratio (HR) = 0.96 95% CI 0.34-2.65, P = 0.929], whereas patients with systolic dysfunction unrelated to AFL had higher mortality rates compared with patients without systolic dysfunction at baseline [HR = 2.88, 95% CI 1.45-5.72, P = 0.002].

AF occurrence after AFL ablation is frequent (>20%), especially in patients with a history of AF, in female patients, and in patients treated with class I antiarrythmics/amiodarone prior to AFL. Since most patients who experience AF after AFL ablation have a CHA2DS2-VASc ≥1, the decision to stop anticoagulants after ablation should be considered on an individual basis.

Permanent AF at baseline was associated with incident heart failure. A substantial proportion of well-managed patients with AF showed AF progression over 1 year. AF progression itself was not strongly related to outcome and may indicate the need to refine the current classification of AF types to enhance clinical utility.

Background: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, and sudden cardiac death represents an important mode of death in these patients. Data evaluating the implantable cardioverter defibrillator (ICD) in this patient population remain scarce. Methods: Nationwide French Registry including all TOF patients with an ICD initiated in 2010 by the French Institute of Health and Medical Research. The primary time to event endpoint was the time from ICD implantation to first appropriate ICD therapy. Secondary outcomes included ICD-related complications, heart transplantation, and death. Clinical events were centrally adjudicated by a blinded committee. Results: A total of 165 patients (mean age 42.2±13.3 years, 70.1% males) were included from 40 centers, including 104 (63.0%) in secondary prevention. During a median (IQR) follow-up of 6.8 (2.5-11.4) years, 78 (47.3%) patients received at least one appropriate ICD therapy. The annual incidence of the primary outcome was 10.5% (7.1% and 12.5% in primary and secondary prevention, respectively, p=0.03). Overall, 71 (43.0%) patients presented with at least one ICD complication, including inappropriate shocks in 42 (25.5%) patients and lead dysfunction in 36 (21.8%) patients. Among 61 (37.0%) primary prevention patients, the annual rate of appropriate ICD therapies was 4.1%, 5.3%, 9.5%, and 13.3% in patients with respectively no, one, two, or ≥ three guideline-recommended risk factors. QRS fragmentation was the only independent predictor of appropriate ICD therapies (HR 3.47, 95% CI 1.19-10.11), and its integration in a model with current criteria increased the 5-year time-dependent area under the curve from 0.68 to 0.81 (p=0.006). Patients with congestive heart failure and/or reduced LVEF had a higher risk of non-arrhythmic death or heart transplantation (HR=11.01, 95% CI: 2.96-40.95). Conclusions: Patients with TOF and an ICD experience high rates of appropriate therapies, including those implanted in primary prevention. The considerable long-term burden of ICD-related complications, however, underlines the need for careful candidate selection. A combination of easy-to-use criteria including QRS fragmentation might improve risk stratification. Clinical Trial Registration: URL: https://clinicaltrials.gov Unique Identifier: NCT03837574

AF and AFL were frequent in MD and increased mortality. AFL could present as 1/1 AFL with a poor tolerance and a risk of misdiagnosis despite frequent conduction disturbances. This arrhythmia could explain wide QRS tachycardia occurring in MD and interpreted as VT.