Abstract 17353: End-Stage Hypertrophic Cardiomyopathy Treated with Cardiac Resynchronization Therapy (CRT)
Background: Treatment options remain limited for a subset of patients with hypertrophic cardiomyopathy (HCM) who develop severe late-stage systolic dysfunction. The impact of CRT in these patients remains uncertain.
Methods: HCM patients who received CRT for standard indications comprised the study cohort, and were initially compared to consecutive nonischemic and ischemic CRT patients. Next, a nested case-control analysis of HCM patients matched by age, gender, medication use, and comorbidity was performed. Echocardiographic outcomes were evaluated at 6 months. Time to all-cause death or first HF hospitalization was assessed at 3 years.
Results: In total, 436 patients were included: 7 patients with HCM, 180 nonischemic (NI), and 249 ischemic (I) patients. HCM patients were more comparable in age to ischemic (66.8 ± 13.8 yrs vs. 72.8 ± 9.5 yrs [I]) patients and older than other nonischemic patients (63.1 ± 13.4 yrs [NI]). Baseline LVEF was higher at baseline (30.7 ± 12% vs. 23.2 ± 7.1% [NI] and 23.9 ± 7.2% [I], p=0.043) in HCM patients, although QRS width was similar across patients (172 ± 30 ms vs. 161 ± 30 ms [NI] and 162 ± 29 ms [I], p=NS). After CRT, HCM patients demonstrated significant LVEF improvement (+9.0 ± 2.8%) commensurate with that found in nonischemic (+10.4 ± 10.4%) patients, and better than in nonischemic (+5.3 ± 10%) patients (p=0.0067). When compared to matched controls, HCM patients demonstrated no significant difference with respect to HF hospitalization (Figure, Panel A) or mortality (Figure, Panel B).
Conclusion: Patients with hypertrophic cardiomyopathy derive echocardiographic benefit after CRT, and demonstrate clinical outcome on par with other matched patients at three years. Further investigation in the treatment of advanced HCM with CRT appears warranted.
- © 2012 by American Heart Association, Inc.