Performance of the Durata implantable cardioverter defibrillator lead: results of an independent multicenter study.

AIMS: The high rate of implantable cardioverter defibrillator (ICD) lead failures related to the Sprint Fidelis' and Riata's design have raised serious concerns about the reliability of ICD leads. The St. Jude Medical Durata family of leads replaced the preceding Riata line following increased rates of lead failure (1.17% per year). The aim of our study was to evaluate the long-term performance of the Durata lead. METHODS: Eight hundred and eighteen Durata ICD leads were implanted in 11 Italian centers. The incidence of lead failure, defined as a sudden rise in long-term pacing or defibrillation impedance and/or a sudden change in R-wave amplitude and capture thresholds, was assessed. The incidences of lead dislodgment and lead perforation were also evaluated. RESULTS: During a median follow-up of 1353 days (3.7 years; 25-75th interquartile range 806-1887 days) lead failure occurred in 16/818 leads (0.54%/year). The overall survival, free of lead failure, was 98.9% at 3 years, 98.2% at 4 years and 97.5% at 5 years. Lead dislodgment occurred in 12/818 leads with an incidence of 0.4%/year. No cases of cardiac perforation were reported. No major adverse events were reported except for two cases of inappropriate shocks as a consequence of failure or dislodgment. CONCLUSION: Our study suggests that the Durata lead does not engender a higher risk of failure. Overall survival, free from lead failure, was found to be higher than previously reported for the Riata lead.

Atrial fibrillation in recipients of cardiac resynchronization therapy device: 1-year results of the randomized MASCOT trial.

BACKGROUND: Atrial fibrillation (AF) is associated with increased morbidity and mortality in patients suffering from heart failure (HF). Patients in New York Heart Association HF classes III or IV, with systolic dysfunction and a wide QRS, are candidates for cardiac resynchronization therapy (CRT), and might benefit from atrial overdrive pacing (AOP). METHODS: The Management of Atrial fibrillation Suppression in AF-HF COmorbidity Therapy (MASCOT) trial enrolled 409 CRT device recipients (79% men), who were randomly assigned to AOP ON (n = 197), versus AOP OFF (n = 197) and followed up for 1 year. Their mean age was 68 +/- 10 years, left ventricular ejection fraction 25 +/- 6%, QRS duration 163 +/- 29 milliseconds. New York Heart Association class III was present in 86% of patients and 19% had a history of paroxysmal AF. The primary study end point was incidence of permanent AF at 1 year. RESULTS: Atrial overdrive pacing increased the percentage of atrial pacing from 30% to 80% (P < .0001), was well tolerated, and did not interfere with (a) delivery of CRT (95% mean ventricular pacing in both groups), (b) response to CRT (70% responders in the control vs 67% in the treatment group), or (c) cardiac function (left ventricular ejection fraction increased from 24.5% +/- 6.2% to 32.7% +/- 10.9% in the control and from 25.8% +/- 6.8% to 33.1% +/- 12.6% in the treatment group). The incidence of permanent AF was 3.3% in both groups. By logistic regression analysis, a history of AF (P < .001) and absence of antiarrhythmic drugs (P = .002) were associated with permanent AF. CONCLUSIONS: In this first trial of a specific AF prevention algorithm in CRT recipients, AOP was safe and did not worsen HF. The prevention algorithm did not lower the 1-year incidence of AF.

Prognostic value of electrocardiograms, ventricular late potentials, ventricular arrhythmias, and left ventricular systolic dysfunction in patients with Duchenne muscular dystrophy.

Myocardial involvement is a common finding in patients with Duchenne-type muscular dystrophy (DMD). Nevertheless, the prognostic values of standard electrocardiogram (ECG), ventricular arrhythmias, ventricular late potentials (LPs), and left ventricular (LV) systolic dysfunction have not been extensively investigated. Eighty-four patients with DMD (aged 18.6 +/- 4.8 years) underwent standard and signal-averaged electrocardiography, 24-hour Holter monitoring, and echocardiography. The prevalence of electrocardiographic abnormalities, frequent ventricular premature complexes, LPs, and LV systolic dysfunction was 71%, 32%, 28%, and 35%, respectively. Median follow-up was 76 months (range 5 to 106). The mortality rate in the follow-up period was 27%. The typical DMD electrocardiographic alterations, ventricular arrhythmic pattern, and LPs were not predictors of mortality. In contrast, the presence of LV systolic dysfunction detected on echocardiography was a powerful predictor of mortality in the follow-up period (p = 0.013, hazard ratio 3.14, 95% confidence interval 1.27 to 7.79). Thus, echocardiographic assessment of LV systolic dysfunction provides prognostic information in patients with DMD. Electrocardiographic alterations, ventricular arrhythmias, and LPs have no prognostic value in predicting mortality in these patients.