Hypertrophic cardiomyopathy in youth: phenotype, genotype, and treatment approaches
Abstract
Hypertrophic cardiomyopathy (HCM) is an inherited disease characterized by pronounced anatomic, clinical, and genetic heterogeneity. Prognosis varies from normal life expectancy without serious complication to severe form requiring early surgical treatment.
Aim of this study is to analyze factors underlying such heterogeneity.
Material and methods. Instrumental evaluation included ECG, Echo CG, MSCT, and MRI with gadolinium. Mutational screening of the 10 genes encoding sarcomeric proteins, and F5 p.R506Q (Leiden) mutation testing.
Results. Surgical treatment with correction of intracardiac abnormalities was performed for 120 HCM patients. We propose structural and anatomical classification of hypertrophic cardiomyopathy based on these data. Early manifestation and indications for surgical treatment before 30 y.o. were found in 21 (17.5%) patients. 17 of 21 patients (81%) had diffuse generalized phenotype with submitral obstruction: whole interventricular septum enlargement, hypertrophic and numerous papillary muscles displaced to the left ventricular apex. Two-level gradient was found in 25% patients. Genetic cause of cardiac hypertrophy was found in 10 patients, and 3 of them had >1 genetic risk factor. All patients were operated successfully, and 6 of them were operated by simultaneous transaortic and transmitral access. 7 patients had a high risk of SCD, and cardioverter-defibrillator was implanted.
Conclusion. Classification of the HCM phenotypes based on anatomic and hemodynamic features was proposed. Diffuse generalize phenotype was the most common finding in patients with early HCM manifestation (before 30 y.o.). This phenotype was associated with rapid progression and severe prognosis.
Keywords:hypertrophic cardiomyopathy, extended myectomy, sudden cardiac death, MYH7, MyBPC3, DNA diagnostics
For citation: Dzemeshkevich S.L., Motreva A.P., Kalmykova O.V., Martyanova Yu.B., Sinitsyn V.E., Mershina E.A., Nikolaeva E.V., Radzhabova G.M., Polyak M.E., Nikityuk T.G., Dombrovskaya A.V., Frolova Yu.V., Solovyeva S.E., Nechepurenko A.A., Zaklyazminskaya E.V. Hypertrophic cardiomyopathy in youth: phenotype, genotype, and treatment approaches. Clin Experiment Surg. Petrovsky J. 2019; 7 (3): 54–62. doi: 10.24411/2308-1198-2019-13006 (in Russian)
Received 19.06.2019. Accepted 25.07.2019.
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