Management of Cardiac Complications

Early treatment with ACE inhibitors is probably war­ranted in DMD when the measured ejection fraction falls below 55% (36,37). The benefits of earlier protec­tive treatment with either ACE inhibitors or ARBs is under investigation.

The management of the cardiomyopathy, seen in Becker muscular dystrophy, is similar to that seen in DMD; however, in cases of severe end-stage cardiomy­opathy, cardiac transplantation should be considered.

Cardiac conduction abnormalities observed in myotonic muscular dystrophy may ultimately require implantation of cardiac pacemakers. In rare instances with cardiomyopathy, treatment may consist of ACE inhibitors, digitalis, and diuretics, based on proven efficacy in cardiomyopathies of other etiologies.

Emery-Dreifuss muscular dystrophy patients with symptomatic bradycardia or heart block should undergo implantation of a permanent cardiac pace­maker. Atrial standstill, atrial fibrillation, and atrial flutter are all disorders in which blood can pool in the atria, leading to thrombus formation and possible embolic events, including stroke. Anticoagulation with warfarin to an international normalized ratio (INR) of 2-3 has demonstrated a reduction in the incidence of stroke in patients with atrial fibrillation. Prompt referral to a cardiologist should be made for children with cardiac signs or symptoms nr screening ECG, echocardiography, or for those with Holter recording abnormalities suggestive of cardiac disease. Late-stage DMD, BMD, and Emery-Dreifuss muscular dystrophy patients should be followed by a cardiologist on a reg­ular basis. Appropriate management of cardiac com­plications in childhood neuromuscular disease will hopefully increase life expectancy.