Long-term outcome and mortality predictors in patients with extremely enlarged left ventricle end-diastolic diameter undergoing cardiac resynchronization therapy

Abstract

Abstract Background Data on efficacy of cardiac resynchronization therapy (CRT) and prognosis of CRT recipients with extremely enlarged left ventricular prior to device implantation are scarce. Aim To determine outcome and mortality predictors in patients with heart failure (HF) and extremely increased left ventricle end-diastolic diameter (LVEDD) treated with cardiac resynchronization therapy. Methods Study population consisted of 1059 consecutive patients with CRT implanted between 2002 and 2019 in a tertiary care university hospital, in a densely inhabited, urban region of Poland (949 subjects [89.6%] with CRT-D; 110 patients with CRT-P [10.4%]). Results The median LVEDD before CRT implantation was 68 mm (56–80). We divided all CRT patients into quartiles as per LVEDD: I <61 mm, II 61–67 mm, III 68–73 mm and IV ≥74 mm. During the median follow-up of 1661 days (10th and 90th percentile: 323–3995) mortality rates for quartiles I–IV were 41.2, 49.6, 55.9 and 68.1%, respectively (P<0.001). The LVEDD ≥74 mm (quartile IV) appeared to be an independent risk factor for death (HR 1.29, 95% CI 1.05–1.6, P=0.02). On multivariable analysis, severe mitral regurgitation (MR; HR 1.54, 95% CI 1.1–2.16, P=0.01) and advanced age (HR 1.02, 95% CI 1.01–1.03, P=0.02) were independent risk factors for death in quartile IV. During observation, mortality rate for quartile IV patients aged >65 years and with severe MR was 90%. Exclusion of subjects with severe MR and aged >65 from quartile IV resulted in similar mortality rate (53.1%) as for patients in lower quartiles. Conclusions Mortality rates in CRT recipients with extremely enlarged LVEDD is significantly higher compared to those with LVEDD <74 mm. CRT offer to HF patients with LVEDD ≥74 mm (and in particular those with accompanying severe MR and aged >65 years) should be very carefully assessed and other HF therapies (i.e. left ventricular assist devices) should be considered, as more than 90% of those die within 4 years since CRT implantation. Funding Acknowledgement Type of funding sources: None.