CLINICAL CHARACTERISTICS OF INFANTILE HYPERTROPHIC CARDIOMYOPATHY

Yao Weiqing, Chen Shubao, Wang Rongfa, Sun Kuan, Huang Meirong

Xinhua Children's Hospital, Shanghai Second Medical University,

Shanghai 200092, China        

 

Purposes: To investigate clinical characteristics of infantile hypertrophic cardiomyopathy (IHCM), so as to improve the diagnosis and treatment.

Methods: Retrospectively analysis the characteristics of clinical presentation, EKG, chest X-ray (CXR), 2-dimensional echocardiography (2DE), cardiac pathology, and outcome of 7 cases of IHCM (all meets WHO/ISFC diagnosis criteria) hospitalized between 1984 and 1996.

Results: With 6 boys and 1 girl in total. Presented with cough and dyspnea in 6/7 cases, cyanosis in 3/7. One case with edema.4/7 cases had systolic murmur in 3-4 LCSs, in which 2 with thrill. 5/7 patients were considered as congenital heart defects (CHD) at initial diagnosis. EKG revealed right ventricular hypertrophy (LVH) in 1/6, right ventricular hypertrophy (RVH) in 4/6. Abnormal Q wave in only 1 case.2DE found that all cases (7/7) had LVH, with symmetrical hypertrophy in 6/7 cases and asymmetrical hypertrophy in only one case. 2/7 cases had whole heart enlargement and low contractility. Only one case with left ventricular turbulent flow in Doppler examination. 5/7 treated with dopamine or dobutamine, digitalis and diuretics. Only one case improved after added with propranolol. 2/7 cases died 2 and 18 days respectively after admission, while others withdrew therapy.

Conclusions: The clinical characteristics of HCM of infants are much different from that of children and adults. Apart from heart murmur there may be marked symptoms of heart failure, even cyanosis. RVH is common while abnormal Q wave is rare in EKG, usually with heart enlargement in CXR. In time 2DE is helpful in early diagnosis. It suggests poor outcome if symptoms and heart failure appear in the first year of life.  β-blocker should be given if there is septal ventricular hypertrophy and outflow obstruction, while digitalis and diuretics as well as angiotensin converting enzyme inhibitors used if with ventricular enlargement and poor contractility. The actual incidence of IHCM may be higher than suggested before, since more asymptom cases are being reported as a result of widely and frequently using of 2DE examination.

 
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