Long-term outcome of conservative and invasive treatment in patients with hypertrophic obstructive cardiomyopathy.

Treatment for patients with hypertrophic obstructive cardiomyopathy (HOCM) can be either conservative or invasive (alcohol septal ablation (ASA) and myectomy). As there is no clear consensus on the long-term effects of these different strategies, the aim was to compare the long-term outcome in a large tertiary referral university hospital. We retrospectively included 106 HOCM patients. Twenty-nine (27.4%) patients were treated conservatively, 25 (23.6%) underwent ASA and 52 (49.0%) myectomy. Endpoints were all-cause mortality and sudden cardiac death (SCD)-related events (including SCD, aborted SCD and appropriate ICD shocks). Kaplan-Meier survival analysis and Cox proportional hazard regression models were used. The mean follow-up period was 7.7 ± 4.9 years. Overall, there was no significant difference in survival between the three treatment strategies ( = 0.7). Annual rates of SCD-related events at 5 years and the complete follow-up period were significantly higher ( = 0.034) after conservative treatment (4.9%/year and 2.7%/year, respectively) compared to ASA (0.9%/year, 0.5%/year) and myectomy (1.0%/year, 0.6%/year). Independent predictors of SCD-related events were: conservative treatment (HR 10.66; 1.88-60.55), a known mutation (HR 9.36; 1.43-61.20), left ventricular wall thickness (LVWT) > 30 mm (HR 6.48; 1.05-39.92) and non-sustained VT (HR 16.82; 2.29-123.29). Invasive treatment resulted in a significant higher proportion of patients requiring pacing ( = 0.033). Long-term mortality rates for patients with HOCM are similarly low between treatment groups. However, conservative treatment was associated with SCD-related events, as were known mutations, increased LVWT and non-sustained VT. Invasive treatment was associated with a higher need for implantation of a pacemaker.