Incidence of appropriate anti-tachycardia therapies after elective generator replacement in patient with heart failure initially implanted with a defibrillator for primary prevention: Results of a meta-analysis.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) is an effective therapy to reduce mortality in heart failure. When the ICD generator approaches the end of life, most of the patients undergo an elective generator replacement (GR) even if they no longer meet implantation criteria. Whether arrhythmic risk should be re-assessed at the time of GR is still an open question. The aim of our study was to assess, via a meta-analysis, the occurrence of appropriate ICD therapies after GR in patients stratified based on the presence/absence of ICD indication at the time of GR.

METHODS: Via a systematic literature search for primary prevention studies (January 2000-Sectember 2018), 2976 studies were analyzed. 6 studies were lastly included. Patients were categorized into two groups: "with ICD indication" in case of LVEF≤35% at the time of GR and/or appropriate therapies during the first ICD life; "without ICD indication" in case of a LVEF>35% and no previous ICD therapies. Incidences of appropriate ICD therapies were computed as number of events per 100 person-year.

RESULT: We included 478 pts. (65%) with and 255 patients (35%) without persistent ICD indication. The incidence of appropriate therapies was 12.3/100-person-year in patients with vs. 3.4 in patients without persistent ICD indication (2.98 fold higher risk of ICD therapies).

CONCLUSION: Patients who no longer meet ICD implantation criteria at the time of GR present a significantly lower risk of appropriate ICD therapies after GR. The results of this study underline the importance of an arrhythmic risk re-stratification at the time of GR.