The course of left ventricular function was evaluated using M-mode and Doppler echocardiography in 34 patients with Fukuyama-type congenital muscular dystrophy (FCMD), in a study at the Tokyo Women’s Medical University, Tokyo, Japan. Ages ranged from 6 months to 30 years (median, 6 years). Diagnosis of FCMD was based on haplotype analysis, neurologic examination and muscle biopsy. The haplotype was ancestral homozygous in 21 and heterozygous in 10 patients. The interval between echocardiographic examinations ranged from 12 months to 11 years (median, 4 years). ECG abnormalities were present in 20 (59%) patients: a tall R wave in 20, and a deep but narrow Q wave over lead V6 in 2 patients. The PG interval was normal. Decreased left ventricular systolic function (expressed as left ventricular fractional shortening [LVFS]) was present in 16 (47%) patients. The finding of LVFS was significantly correlated with age; LVFS was normal in patients <10 years and reduced in patients >15 years of age. LVFS in 16 patients with ancestral heterozygotes was not significantly different from that in 9 patients with homozygotes. LVFS was not significantly different in 3 groups with mild, moderate, and severe skeletal muscle involvement. All 5 patients who died during follow-up had decreased LVFS. They had not received heart-failure therapy. Three patients died of respiratory failure at 2, 27, and 31 years of age. Two patients died of heart failure at 16 and 17 years of age. Autopsy findings showed multifocal fibrosis throughout the LV wall, especially severe in those with heart failure. LVFS was increased significantly in 5 patients who received ACE inhibitors. [1]

COMMENT. Fukuyama-type congenital muscular dystrophy is frequently complicated by cardiac involvement after 10 years of age. Treatment with ACE inhibitors and, if needed, beta-blockers, when patients develop early signs of left ventricular dysfunction, may delay the onset of heart failure. Routine cardiac evaluation, including echocardiograms and follow-up, is recommended, especially in older children.

Treatment of the heart in Duchenne muscular dystrophy (DMD) is discussed in an editorial [2]. Multicenter trials are recommended, since reports of treatment with ACE inhibitors and steroids are variable. Cardiomyopathy develops in most patients with DMD by age 18 years, and is the leading cause of death in 10-40%. Initiating therapy at the pre-symptomatic stage of LV dysfunction may delay the onset of cardiac failure and improve prognosis. [3]