Objectives: Cardiac genetic counselling and testing for inherited cardiomyopathies have become essential aspects of cardiovascular care. A genetic diagnosis in a family can offer an invaluable tool for cascade genetic testing of at-risk relatives. A careful clinical and individualized approach to genetic cardiomyopathies is now needed to guarantee the best care possible. We report the results of our first-year genetic cardiomyopathies single-centre experience.
Methods: From September 2021, 69 genetic tests have been carried out at Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico of Milan by the staff of a new specific clinical service dedicated to genetic cardiomyopathies.
Results: The present study collects the data of 69 patients who underwent genetic testing and clinical follow up at our centre in suspicion of underlying genetic etiology of disease. Next generation sequencing was adopted to conduct genetic testing either by a customized panel of 54 specific genes for cardiomyopathies or by a clinical exome (180 genes). Time required for reporting and patient communication were 8 and 12 weeks, respectively. Female sex was 36%, mean age was of 53.2 ± 21.3 years. The main indications for genetic testing were dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). Figure 1. 41% of DCM and 50% of HCM patients tested positive for a pathogenic or likely pathogenetic mutation.
Cascade genetic tests conducted on at-risk relatives were 21 (30%). Among these subjects, 38% resulted positive at genetic screening and 57% were in turn positive at phenotypic screening. The genes hit by pathogenic or likely pathogenetic mutations are illustrated in Figure 2.
Conclusion: The first year of a specific clinical service dedicated to genetic cardiomyopathies made it possible to identify a substantial number of patients and at-risk relatives affected by pathogenic or likely pathogenetic genetic mutations.