Marked right ventricular outflow obstruction in two children with hypertrophic cardiomyopathy

• Published in: Journal of cardiography Vol. 15; no. 3; p. 931
• Main Authors: Matsunaga, S, Rikitake, N, Yoshioka, F, Kato, H
• Format: Journal Article
• Language: Japanese
• Published: Japan 01.09.1985
• Subjects: Cardiac Output; Cardiomyopathy, Hypertrophic - physiopathology; Child; Female; Heart - physiopathology; Humans; Infant
• ISSN: 0386-2887

Two children, aged one year and nine months, and six years, both with hypertrophic cardiomyopathy, presented as severe right ventricular outflow obstruction were presented. Initially, both of them were suspected of having heart disease because of precordial systolic murmurs. Their tentative diagnosis was pulmonary stenosis. Their apex cardiograms and carotid pulse waves were not diagnostic. Asymmetrical septal hypertrophy with systolic anterior motion of the mitral valve was identified by echocardiography in both cases. Cardiac catheterization revealed left ventricular outflow tract pressure gradients of 5 mmHg and 30 mmHg, respectively. The right ventricular peak systolic gradient was 100 mmHg and 82 mmHg and left ventricular end-diastolic pressure was 26 mmHg and 18 mmHg, respectively. Selective right and left ventricular angiocardiograms demonstrated severe right ventricular outflow obstruction, and hypertrophy of the interventricular septum. One of them underwent resection of the right ventricular outflow tract muscle, which showed histological findings characteristic of hypertrophic cardiomyopathy. This patient died suddenly at the age of 10 years. Infants or young children with hypertrophic cardiomyopathy often have associated predominant right ventricular outflow tract obstruction, progressive congestive heart failure, and death. Therefore, correct diagnosis and careful treatment are mandatory for proper management.