Worse prognosis with gene mutations of beta-myosin heavy chain than myosin-binding protein C in Chinese patients with hypertrophic cardiomyopathy

Abstract

Background: No data are available on survival analysis and longitudinal evolution of patients with gene mutations of beta-myosin heavy chain (MYH 7) and myosin binding protein C (MYBPC3) in Chinese. Hypothesis: To prospectively investigate whether different gene mutations confer distinct prognosis. Methods: We performed a prospective study in 70 HCM patients and 46 genetically affected family members without HCM-phenotype with direct DNA sequencing of MYH7 and MYBPC3, clinical assessments, and 5.8 ± 1.8 years follow-up. Results: After follow-up, more surgical intervention (8/52 versus 0/18, p<0.001), higher sudden death risk (7/52 versus 0/18, p<0.001) and shorter life span were found in patients with MYH7 mutations than in patients with MYBPC3 mutations (45.1 ± 14.0 versus 73.5 ± 7.5 years, p = 0.03). Seven of the 27 mutation carriers of MYH7 had clinical presentations of HCM, but no carriers of MYBPC3 mutations developed to HCM during follow-up. Maximal wall thickness was thicker in the patients carrying mutations in the global region of MYH7 than in those carrying mutations in the rod region of MYH7 (21.5 ± 6.6 versus 15 ± 6.1 mm, p<0.05) at baseline. More sudden death (7/41 versus 0/11) and left ventricular dysfunction (NYHA Class III ∼ IV, 17/32 versus 1/10) were identified in patients with mutations in the global region of MYH7 than in patients with other mutations. Conclusions: MYH7 mutations, especially in the global region, cause malignant clinical phenotypes © 2008 Wiley Periodicals, Inc.