Updated Performance of the Micra Transcatheter Pacemaker in the Real-World Setting : a Comparison to the Investigational Study and a Transvenous Historical Control

BACKGROUND: Early results of the Micra Investigational Device Exemption (IDE) study and Micra Post-Approval Registry (PAR) demonstrated excellent safety and efficacy performance; however, intermediate-term results across a large patient population in the real-world setting have not been evaluated. OBJECTIVES: We report updated performance of the Micra transcatheter pacemaker from a worldwide PAR and compare it with the IDE study as well as a transvenous historical control. METHODS: The safety objective of the analysis was system- or procedure-related major complications through 12 months postimplantation. We compared the major complication rate with that of the 726 patients from the IDE and with a reference data set of 2667 patients with transvenous pacemakers by using a Fine-Gray competing risk model. RESULTS: The Micra device was successfully implanted in 1801 of 1817 patients (99.1%). The mean follow-up period was 6.8 \ub1 6.9 months. Through 12 months, the major complication rate was 2.7% (95% confidence interval [CI] 2.0%-3.7%). The risk of major complications for Micra PAR patients was 63% lower than that for patients with transvenous pacemakers through 12 months postimplantation (hazard ratio 0.37; 95% CI 0.27-0.52; P < .001). The major complication rate trended lower in the PAR than in the IDE study (hazard ratio 0.71; 95% CI 0.44-1.1; P = .160), driven by the lower pericardial effusion rate in the PAR. There were 3 cases of infection associated with the procedure, but none required device removal and there were no battery or telemetry issues. Pacing thresholds were low and stable through 12 months postimplantation. CONCLUSION: Performance of the Micra transcatheter pacemaker in international clinical practice remains consistent with previously reported data. Major complications were infrequent and occurred 63% less often compared to transvenous systems

[Which antithrombotic treatment in case of atrial fibrillation and coronary heart disease?].

International audienc

Long-term follow-up on high-rate cut-off programming for implantable cardioverter defibrillators in primary prevention patients with left ventricular systolic dysfunction

International audienc

Safety of deferring the reimplantation of pacing systems after their removal for infectious complications in selected patients: A 1-year follow-up study

Introduction: Recent expert consensus guidelines mention that one of the principles for infected device replacement following removal is to "reevaluate carefully if there is a continued need for a new cardiac device replacement." This is a Class I recommendation, which nevertheless suffers from a very low level of evidence (level of evidence C), since no study has revisited the systematic practice of reimplanting the same device based on a meticulous clinical reassessment. In the present paper, we examined the safety of withholding the implantation of pacing systems in selected patients. Methods and Results: Between January 2005 and December 2007, 188 consecutive patients underwent extractions of infected pacing systems at 2 medical centers. "Low-risk" patients were identified by (1) a spontaneous heart rate >45 bpm, (2) no symptomatic asystole during monitoring, (3) QRS duration <120 ms when history of AV block was noted, (4) no high-degree AV block during continuous monitoring. They remained device-free, unless an adverse clinical event occurred mandating the reimplantation. The primary study endpoint was rate of sudden death and syncope after a 12-month follow-up. Among the 74 (39.4%) "low-risk" patients, a single patient suffered a bradycardia-related syncopal event corresponding to a 1.3% (95% CI, 0.0-3.9) rate of primary endpoint. Pacing systems were also reimplanted in 24 patients (32.4%) for syncope (n = 1), nonsevere bradycardia-reated symptoms (n = 17), cardiac resynchronization (n = 2), and for reassurance in 4 asymptomatic patients. Conclusion: After removal of infected pacing systems, these preliminary data demonstrated that a strategy of nonsystematic device reimplantation associated with close surveillance was safe in "low-risk" patients, allowing the administration of antimicrobials in a device-free state. © 2009 Wiley Periodicals, Inc

Impact of Pacing Site on QRS Duration and Its Relationship to Hemodynamic Response in Cardiac Resynchronization Therapy for Congestive Heart Failure

Cardiolog