Survival analysis in hypertrophic cardiomyopathy caused by the three most common pathogenic TPM1 variants
Abstract Purpose To evaluate survival free of cardiovascular events in carriers of the three most frequent TPM1 pathogenic hypertrophic cardiomyopathy (HCM) variants. Methods Clinical and genetic data on families carrying TPM1 variants in the literature and identified in our center were systematically revised and collected in a database. Classification of variant's pathogenicity was in accordance with ACMG criteria. We evaluated available follow-up data and constructed Kaplan-Meier survival curves to cardiovascular death (sudden death, appropriate cardiodefibrillator shock, heart failure death, and stroke-related death) or heart transplant. Long-rank test was used to compare event-free survival time. Results 562 carriers (343 HCM-probands and 219 relatives; 51.3% male carriers) were identified carrying 73 missense variants considered disease causing. TPM1 p.Asp175Asn (87 probands, 109 relatives, 6 unaffected), p.Arg21Leu (52 probands, 25 relatives, 16 unaffected), and p.Met281Val (37 probands, 8 relatives, 9 unaffected) were the most prevalent HCM-variants. Among these three variants, survival data was reported for 508 individuals. Eight-nine carriers had suffered events: 74 sudden deaths (55% males), nine heart failure deaths (44% males), two transplants (50% males), and five stroke-related death (25% males). Incidence of cardiovascular death or transplant was similar between TPM1 p.Arg21Leu and p.Met281Val (p=0.75) and different than p.Asp175Asn (p=0.03 and p=0.06, respectively) and all TPM1 variants (p=0.004 and p=0.04). Analysis by sex showed TPM1 p.Arg21Leu female carriers had better prognosis than p.Asp175Asn male carriers (p=0.048) and all TPM1 male and female carriers (p=0.02 and p=0.04) (curves not showed in the graph). Conclusion TPM1 p.Arg21Leu and p.Met281Val could have a better prognosis than p.Asn175Asn and all other TPM1 missense variants in HCM. No marked difference was observed between male and female carriers. More than 80% of the events were arrhythmic deaths. FUNDunding Acknowledgement Type of funding sources: Private company. Main funding source(s): HEALTH IN CODE SL