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Background— The number of patients with longer follow-up after implantation of an implantable cardioverter-defibrillator is increasing continuously. Defibrillation lead failure is a typical long-term complication. Therefore, the long-term reliability of implantable cardioverter-defibrillator leads has become an increasing concern. The aim of the present study was to assess the annual rate of transvenous defibrillation lead defects related to follow-up time after lead implantation. Methods and Results— A total of 990 consecutive patients who underwent first implantation of an implantable cardioverter-defibrillator between 1992 and May 2005 were analyzed. Median follow-up time was 934 days (interquartile range, 368 to 1870). Overall, 148 defibrillation leads (15%) failed during the follow-up. The estimated lead survival rates at 5 and 8 years after implantation were 85% and 60%, respectively. The annual failure rate increased progressively with time after implantation and reached 20% in 10-year-old leads ( P <0.001). Lead defects affected newer as well as older models. Patients with lead defects were 3 years younger at implantation and more often female. Multiple lead implantation was associated with a trend to a higher rate of defibrillation lead defects ( P =0.06). The major lead complications were insulation defects (56%), lead fractures (12%), loss of ventricular capture (11%), abnormal lead impedance (10%), and sensing failure (10%). Conclusions— An increasing annual lead failure rate is noted primarily during long-term follow-up and reached 20% in 10-year-old leads. Patients with lead defects are younger and more often female.

Background: Optimal treatment of patients with persistent atrial fibrillation (AF) and heart failure (HF) with reduced left ventricular ejection fraction (LVEF) and an indication for internal defibrillator therapy is controversial. Methods: Patients with persistent/longstanding persistent AF and LVEF ≤35% were randomly allocated to catheter ablation of AF or best medical therapy (BMT). The primary study end point was the absolute increase in LVEF from baseline at 1 year. Secondary end points included 6-minute walk test, quality-of-life, and NT-proBNP (N-terminal pro-brain natriuretic peptide). Pulmonary vein isolation was the primary ablation approach; BMT comprised rate or rhythm control. All patients were discharged after index hospitalization with a cardioverter-defibrillator or cardiac resynchronization therapy defibrillator implanted. The study was terminated early for futility. Results: Of 140 patients (65±8 years, 126 [90%] men) available for the end point analysis, 68 and 72 patients were assigned to ablation and BMT, respectively. At 1 year, LVEF had increased in ablation patients by 8.8% (95% CI, 5.8%–11.9%) and in BMT patients by 7.3% (4.3%–10.3%; P =0.36). Sinus rhythm was recorded on 12-lead electrocardiograms at 1 year in 61/83 ablation patients (73.5%) and 42/84 BMT patients (50%). Device-recorded AF burden at 1 year was 0% or maximally 5% of the time in 28/39 ablation patients (72%) and 16/36 BMT patients (44%). There was no difference in secondary end point outcome between ablation patients and BMT patients. Conclusions: The AMICA trial (Atrial Fibrillation Management in Congestive Heart Failure With Ablation) did not reveal any benefit of catheter ablation in patients with AF and advanced HF. This was mainly because of the fact that at 1 year, LVEF increased in ablation patients to a similar extent as in BMT patients. The effect of catheter ablation of AF in patients with HF may be affected by the extent of HF at baseline, with a rather limited ablation benefit in patients with seriously advanced HF. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00652522.

AimsThe aim of this study was to investigate the effect of contact-to-balloon time on mortality in ST-segment elevation myocardial infarction (STEMI) patients with and without haemodynamic instability.Methods and resultsUsing data from the prospective, multicentre Feedback Intervention and Treatment Times in ST-Elevation Myocardial Infarction (FITT-STEMI) trial, we assessed the prognostic relevance of first medical contact-to-balloon time in n = 12 675 STEMI patients who used emergency medical service transportation and were treated with primary percutaneous coronary intervention (PCI). Patients were stratified by cardiogenic shock (CS) and out-of-hospital cardiac arrest (OHCA). For patients treated within 60 to 180 min from the first medical contact, we found a nearly linear relationship between contact-to-balloon times and mortality in all four STEMI groups. In CS patients with no OHCA, every 10-min treatment delay resulted in 3.31 additional deaths in 100 PCI-treated patients. This treatment delay-related increase in mortality was significantly higher as compared to the two groups of OHCA patients with shock (2.09) and without shock (1.34), as well as to haemodynamically stable patients (0.34, P < 0.0001).ConclusionsIn patients with CS, the time elapsing from the first medical contact to primary PCI is a strong predictor of an adverse outcome. This patient group benefitted most from immediate PCI treatment, hence special efforts to shorten contact-to-balloon time should be applied in particular to these high-risk STEMI patients.Clinical Trial RegistrationNCT00794001.

The Brugada syndrome (BS) is a distinct form of idiopathic ventricular fibrillation and may cause sudden cardiac death in healthy young individuals. In the surface ECG, BS can be recognized by an atypical right bundle branch block and ST-segment elevation in the right precordial leads. Mutations in the cardiac sodium channel gene SCN5A are only known to cause BS. In a multi-center effort, we have collected clinical data on 44 unrelated index patients and family members and performed a complete genetic analysis of SCN5A. In 37% the disease was familial, whereas in the majority it was sporadic (63%). Five novel SCN5A mutations (2602delC, resulting in: E867X; 2581_2582del TT: F861fs951X; 2673G>A: E1225K; 4435_4437delAAG: K1479del; and 5425C>A: S1812X) were found and were randomly located in SCN5A. Mutation frequencies (SCN5A+) differed significantly between familial (38%) and sporadic disease (0%) (p=0.001). Disease penetrance was complete in the SCN5A+ adult patients, but incomplete in SCN5A+ children (17%). Genetic testing of SCN5A is especially useful in familial disease to identify individuals at cardiac risk. In sporadic cases, however, a genetic basis and the value of mutation screening has to be further determined. These results are in line with a possibly genetic and clinical heterogeneity of BS.