Mutation profile of FLNC gene and its prognostic relevance in patients with hypertrophic cardiomyopathy

Abstract

Background: Filamin C (FLNC) mutation was reported as a cause of HCM, with a high probability of sudden cardiac death. However, the mutation profile of FLNC, and its relationship with phenotypic expression in HCM, remains to be elucidated. Methods: In this study, FLNC gene was sequenced in 540 HCM patients and 307 healthy controls. Results: We found that 39 (7.2%) patients carried FLNC mutations, with a similar frequency to that of controls (4.2%, p = 0.101). Pedigree analysis showed that mutations were not well segregated with HCM. The baseline characteristics between HCM patients, with and without mutations, were comparable. FLNC mutations did not increase the risk for either all-cause mortality (HR 0.746, 95% CI 0.222–2.295, p = 0.575) or cardiac mortality (HR 0.615, 95% CI 0.153–1.947, p = 0.354) in HCM patients during a follow-up of 4.7 ± 3.2 years. Moreover, there was no significant difference in survival free from sudden cardiac arrest (HR 0.721, 95% CI 0.128–3.667, p = 0.660) and heart failure (HR 0.757, 95% CI 0.318–1.642, p = 0.447). Conclusions: FLNC mutations were common in both HCM patients and healthy population. The pathogenicity of FLNC mutations detected in HCM patients and its association with the clinical outcomes should be cautiously interpreted.