Sudden cardiac death prevention in a patient with diffuse generalized hypertrophic cardiomyopathy, associated
with two mutations in MYH7 and MyBPC3 genes
Abstract
Hypertrophic cardiomyopathy (HCM) is a common inherited disease characterized by pronounced clinical and genetic heterogeneity. The causes for the considerable variability in clinical manifestations of the HCM among family members remain unclear. The development of surgical approaches for HCM treatment allowed reducing annual mortality in HCM patients from 2% to 0.5%, mainly due to sudden cardiac death (SCD) prevention. However, SCD risk assessment, the selec- tion of patients for implantable cardioverter-defibrillator (ICD), and the timing of interventions are still debatable.
The most threatening HCM phenotype with a high risk of SCD and early progression of heart failure characterized by hypertrophy of the entire septum (and not just its basal parts) with generalization of the process to the apex, anterior lateral wall, and exceed and hypertrophic papillary muscles. Here we discuss a clinical history of 15 year-old patient with a familial form of HCM, unusually se- vere diffuse generalized phenotype, and a combination of two heterozygous mutations, p.G263R in the MyBPC3 gene and p.G741R in the MYH7 gene. The patient underwent an expanded myectomy with immobilization of the papillary muscles, and ICD implantation. We believe that combination of complex genotype with diffuse generalized cardiac phenotype might be considered as an absolute indication for septal myectomy with cardiopulmonary bypass and ICD implantation. Such a com- bined surgical intervention should prevent sudden cardiac death and the heart failure progression.
Keywords:hypertrophic cardiomyopathy, risk assessment of sudden cardiac death, MYH7, MyBPC3, mutations de novo, double heterozygote, expanded myoectomy, implantable cardioverter-defibrillator
Clin Experiment Surg. Petrovsky J. 2018; 6 (3): 78–84.
doi: 10.24411/2308-1198-2018-13008. Received: 16.03.2018. Accepted: 10.08.2018.
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