Abstract 9364: MADIT-CRT: Resynchronization Patients Experience More Complications Than ICD-Only Patients but Outcomes are Not Significantly Impacted

Abstract

BACKGROUND and METHODS: MADIT-CRT randomized 1820 patients with mild or asymptomatic heart failure symptoms, ejection fraction below 0.30 and QRS wider than 0.13 s in a 3:2 ratio to cardiac resynchronization therapy (CRT) with an ICD versus ICD alone and demonstrated a 41% reduction in heart failure (HF) events. CRT therapy requires additional lead(s) over a standard ICD. The additional LV (and RA) leads may contribute to an excess of complications with CRT. Lead or procedure-related complications could in turn lead to increased morbidity (such as heart failure (HF) events) and mortality in patients experiencing them. In this MADIT-CRT sub-study we sought to determine if complications were greater in the CRT arm and if patients experiencing a complication had unfavorable outcomes. Complications were classified by timing (0-30 days, > 30 days) and severity (non-severe and severe). HF and mortality events were adjudicated by a blinded events committee. RESULTS: Within the first 30 days, severe complications occurred significantly more frequent in the CRT arm than in the ICD-only arm, 5% vs 3% respectively (p=0.033). Between 30 days and end of follow-up, severe complications were similar in frequency in the two arms (p=0.223). Non-severe complications also were more frequent in the CRT arm than the ICD arm both within the first 30 days, 23% vs 9% respectively (p<0.01), and between day 30 and end of follow-up, 24% vs 15% (p,0.01). Patients experiencing either non-severe or severe complications had a similar HF or death event rate compared with patients free from complications (Figure). CONCLUSIONS: Severe complications occurred more frequently during the first 30 days in the CRT arm of MADIT-CRT and non-severe complications were more frequent throughout follow-up in the CRT arm. Fortunately, patients experiencing these complications as a group did not suffer more HF or death event rates.