Active periodic electrograms in remote monitoring of pacemaker recipients: the PREMS study.

AIMS: Remote monitoring (RM) is considered as a standard of care for pacemaker recipients. Remote monitoring systems provide calendar-based intracardiac electrogram recordings (IEGM) only with the current pacemaker settings (passive IEGM). PREMS (Pacemaker Remote Electrogram Monitoring Study), an observational, multicentre trial, prospectively evaluated the clinical value of an active IEGM (aIEGM), including three 10-s sections (passive IEGM, encouraged sensing, and encouraged pacing), compared to other RM data and to its passive IEGM section. Secondary objectives included the added value of the aIEGM to fully assess the sensing and pacing functions of each lead. METHODS AND RESULTS: Patients were enrolled within 3 months after pacemaker implantation and followed until the first transmitted aIEGM, which was analysed together with all other RM data. In total, 567 patients were enrolled (79 ± 9 years, 62% men, 19% single-chamber, and 81% dual-chamber pacemakers). Of 547 aIEGMs transmitted in 547 patients, 161 [29.4%; 95% confidence interval (95% CI) 25.6-33.3%] indicated at least one anomaly non-detectable with certainty-or at all-on other RM data, including atrial arrhythmia, extrasystoles, undersensing, oversensing, and loss of capture. In 21.7% of cases the detected events deserved a corrective action. The sensing and pacing function of each lead could be fully assessed in 77.3% of aIEGM (95% CI 72.6-82.0%) vs. 15.5% (95% CI 11.4-19.6%) when considering only the passive IEGM section (P < 0.001). CONCLUSION: An active IEGM improves the clinical value of remote pacemaker follow-up. Furthermore, compared to a passive IEGM, the aIEGM increases the capability to fully assess remotely the sensing and pacing functions.

Defibrillation testing in everyday medical practice during implantable cardioverter defibrillator implantation in France: analysis from the LEADER registry.

BACKGROUND: Defibrillation testing (DT) is usually performed during implantable cardioverter defibrillator (ICD) implantation. AIMS: We conducted a multicentre prospective study to determine the DT procedures used in everyday practice, to compare the characteristics of patients with or without DT, and to compare severe adverse events in these two populations during implantation and follow-up. METHODS: The LEADER registry enrolled 904 patients included for primo-implantation of a single (n=261), dual (n=230) or triple (n=429) defibrillation system in 42 French centres. RESULTS: Baseline characteristics of patients (62.0 ± 13.5 years; 88% men; primary indication 62%) who underwent ventricular fibrillation (VF) induction (VF induction group, n=810) and those who did not (untested group, n=94, representing 10.4% of the entire study population) revealed that the untested group were older (P<0.01), had a lower left ventricular ejection fraction, a wider QRS complex and a higher New York Heart Association class and were more often implanted for primary prevention (P<0.001 for all). The main reason given for not performing ICD testing was poor haemodynamic condition (59/94). At 1 year, the cumulative survival rate was 95% in tested patients and 85% in untested patients (P<0.001), mainly because of heart failure deaths. There was one sudden cardiac death in the VF induction group and none in the untested group (P=1.000). CONCLUSIONS: In this study, more than 10% of ICD patients were implanted without VF induction. Untested patients appeared to be sicker than tested patients, with a more severe long-term outcome, but without any difference in mortality due to arrhythmic events.

Electrophysiological study with prophylactic pacing and survival in adults with myotonic dystrophy and conduction system disease.

CONTEXT: Up to one-third of patients with myotonic dystrophy type 1 die suddenly. Thus far, no intervention has effectively prevented sudden death. OBJECTIVE: To determine whether an invasive strategy based on systematic electrophysiological studies and prophylactic permanent pacing is associated with longer survival in patients presenting with myotonic dystrophy type 1 and major infranodal conduction delays than a noninvasive strategy. DESIGN, SETTING, AND PATIENTS: A retrospective study, the DM1 Heart Registry included 914 consecutive patients older than 18 years with genetically confirmed myotonic dystrophy type 1 who were admitted to the Neurological Unit of the Myology Institute of Pitié-Salpêtrière Hospital, a teaching medical center in Paris, France, between January 2000 and December 2009. INTERVENTIONS: Among 486 patients whose electrocardiogram showed a PR interval greater than 200 milliseconds, a QRS duration greater than 100 milliseconds, or both, the outcome of 341 (70.2%) who underwent an invasive strategy was compared with 145 (29.8%) who underwent a noninvasive strategy. A propensity score risk adjustment and propensity-based matching analysis was used to account for selection biases. MAIN OUTCOME MEASURES: Rates of overall survival (main outcome measure) and sudden death, respiratory death, and other deaths (secondary outcome measures). RESULTS: Over a median follow-up of 7.4 years (range, 0-9.9 years), 50 patients died in the invasive strategy group and 30 died in the noninvasive strategy group (hazard ratio [HR], 0.74 [95 CI, 0.47-1.16]; P = .19), corresponding to an overall 9-year survival of 74.4% (95% CI, 69.2%-79.9%). Regardless of the technique used to adjust for between-group differences in baseline characteristics, the invasive strategy was associated with a longer survival, with adjusted HRs ranging from 0.47 (95% CI, 0.26-0.84; P = .01) for a covariate-adjusted analysis of propensity-matched data to 0.61 (95% CI, 0.38-0.99; P = .047) for an analysis adjusted for propensity score quintiles. The survival difference was largely attributable to a lower incidence of sudden death, which occurred in 10 patients in the invasive strategy group and in 16 patients in the noninvasive strategy group, with HRs ranging from 0.24 (95% CI, 0.10-0.56; P = .001) for an analysis adjusted for propensity score quintiles and covariates to 0.28 (95% CI, 0.13-0.61; P = .001) for an unadjusted analysis of propensity-matched data. CONCLUSION: Among patients with myotonic dystrophy type 1, an invasive strategy was associated with a higher rate of 9-year survival than a noninvasive strategy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01136330.