205 Ventricular arrhythmias in cardiac pacing patients multicentric study

Abstract

Patients implanted with dual chamber (DC) pacemakers (PM) have frequent episodes of arrhythmia. The interest of memory functions (MF) featuring EGM recordings to recognize and characterize these arrhythmias, particularly at the ventricular level, is still not well evaluated. The goal of this study is to establish the pertinence of MF at the ventricular level by repeated analysis at follow-up of the data recorded in the PM memories. A prospective series of 405 patients (76 +/− 10 yrs), M 59%, F 41% implanted with DC Kappa PMs (Medtronic, MN, USA) for atrio-ventricular block (37%) and sinus dysfunction (50%) were seen at two post implant semestrial follow-ups, at 6 months (F/u1) and at 12 months (F/u2). 83 pts (20%) at F/u1 and/or F/u2 showed ventricular tachycardias (VT) defined as at least 5 consecutive complexes at a frequency > 175 bpm for a total of 102 follow-ups (17%). 55 pts (14%) showed VT at F/u1, 47 (12%) at F/u2 and only 19 (5%) at both F/u1 and F/u2. VT occurrence was statistically independent from mode switch episodes from the atrial level. Analysis showed that age, pacing indication, pacing mode and cumulated percentage of pacing are not factors in the presence of VT. In the VT group, 65% of patients present cardiopathy, with an ejection fraction of 54 +/− 17%. We observe that cardiopathy, is a statistical difference with the rest of the population of this study (52%, p < 0.05). In our series, VT is frequent observed in 20% of PM patients implanted for standard indications at 6 and 12 months follow-ups. 2/3 of these patients show arrhythmia from the first 6 months f/u and 1/4 of these patients at both 6 and 12 months f/u. 1 year of follow up seems to demonstrate best sensitivity for VT detection. MF featuring EGM recordings are a tool for reliable diagnostic and monitoring of these events. Further studies are required to evaluate the prognostic significance of these arrhythmias.