SIBLINGS WITH RESTRICTIVE SYNDROME AND HYPERTROPHIC CARDIOMYOPATHY: A RARE CASE OF SUCCESSFUL HEART TRANSPLANTATION

Abstract

PURPOSE: To report the cases of siblings with restrictive syndrome who underwent heart transplantation and whose hearts had histological characteristics of hypertrophic cardiomyopathy (HCM). METHOD: Case1) A 7 year-old boy with recurrent pneumonias and cardiomegaly. Echocardiography showed features of restrictive cardiomyopathy. No pericardial commitment was found. Due to refractory congestive heart failure he was listed and successfully transplanted at the age 14. The analysis of the explanted heart revealed diffuse myocite disarray, with no septal asymmetry or subaortic obstruction. He is currently in clinical follow up for 5 years. Case 2) A 10 year-old female with exertion dyspnea, cyanosis and vomits. Due to the family history, she was referred for investigation. Restrictive cardiomyopathy was diagnosed. She was listed for heart transplant and successfully transplanted at the age of 13. The analysis of the explanted heart showed mild thickening of ventricular walls with no asymmetries or subaortic obstruction and several areas of myocyte disarray and fibrosis. She is currently in clinical follow up for 2 years. Blood samples of our patients were tested for mutations in genes MYH7, MYBPC and Troponin I (most frequently related to HCM in Brazil), but no alterations were found. CONCLUSION: HCM is a genetic condition related to mutations in genes that encode components of the sarcomere. It can rarely present with features of restrictive syndrome. Heart transplant is the therapeutic option for refractory congestive heart failure, before the evolution to pulmonary hypertension, with good clinical outcome.