Abstract 9571: Major Adverse Cardiac Events in Hypertrophic Cardiomyopathy Among Index Patients and Their Affected Relatives

• Published in: Circulation (New York, N.Y.) N.Y.), 2021-11, Vol.144 (Suppl_1), p.A9571-A9571
• Main Authors: Nielsen, Soren K, Hansen, Frederikke G, Fischer, Thomas A, Madsen, Trine, Klausen, Ib C, Møller, Dothe S, Jensen, Morten, Lassen, Jens F, Rasmussen, Torsten Bloch B, Mogensen, Jens
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.144.suppl_1.9571

IntroductionThe incidence of major adverse cardiac events (MACE) is well established among index patients with hypertrophic cardiomyopathy (HCM) carrying pathogenic sequence variants in recognized HCM genes. However, MACE among their affected relatives is unknown. It was the aim to compare the incidence of MACE among index patients with HCM and their affected relatives. MethodsClinical and genetic investigations were performed in consecutive index patients with HCM. Genetic investigations by next-generation sequencing were made in 116 recognized and likely HCM genes, and variants were classified by American College of Medical Genetics and Genomics criteria. Relatives at risk of having HCM were invited for clinical investigations (echocardiography, ECG-recording, and genetic testing when relevant). MACE was defined as a composite endpoint of sudden cardiac death, death due to end-stage heart failure or stroke, and heart transplant. ResultsA total of 453 HCM families underwent clinical and genetic investigations, of whom 40% (183/453) carried pathogenic variants. Among relatives, 383 carried the same variant as the index-patient, and the penetrance of HCM in those was 42% (160/383). The median age of diagnosis was 47 years (p=0.13) in relatives and index patients. MACE occurred in 18% (33/183) of index patients, 18% (28/160) of relatives with HCM, and 0% (0/223) of healthy variant carriers. The median age of MACE was 43 years for index patients and relatives (p=0.48). During eight years of follow-up, incidence rates of MACE were not significantly different between index patients and relatives (1.2%/year vs. 1.5%/year p=0.2). ConclusionsAffected Relatives in HCM families who carried pathogenic sequence variants in recognized HCM genes had the same risk of MACE as index patients. This finding emphasized the importance of family screening, follow-up, and continuous risk stratification to possibly avoid adverse disease complications and sudden death.