Eplerenone Improves Cardiac Function in Duchenne Muscular Dystrophy Patients

A recent study was published in The Lancet Neurology journal showing that a specific cardiac drug is able to induce cardiac function improvement in boys with muscular dystrophy and cardiomyopathy. The study is entitled “Eplerenone for early cardiomyopathy in Duchenne muscular dystrophy: a randomized, double-blind, placebo-controlled trial.”

Cardiomyopathy refers to a disease in the heart muscle (myocardium) in which the heart becomes weaker due to muscle enlargement, rigidness or thickness. Myocardial damage is usually followed by a decrease in left ventricular systolic function that can lead to arrhythmias and heart failure. Cardiomyopathy is known to be a main cause of mortality in patients with Duchenne muscular dystrophy, an inherited disorder due to a defective gene (dystrophin) that results in the degeneration of muscle tissues and impaired locomotion. Duchenne muscular dystrophy has a rapid progression and affects mainly boys.

“With increasing recognition of the effect of cardiomyopathy on morbidity and mortality in Duchenne muscular dystrophy, improved strategies are needed to change the natural history of declining left ventricular systolic function and to attenuate its sequelae,” wrote the research team.

Eplerenone is a cardiac medication, used alone or in combination with other drugs to treat high blood pressure. In this study, the authors evaluated the efficacy of eplerenone in patients suffering from Duchenne muscular dystrophy and early myocardial disease.

A randomized, double-blind, placebo-controlled trial was conducted with 42 boys who were 7 years old or older with Duchenne muscular dystrophy, myocardial damage identified by late gadolinium-enhanced cardiac magnetic resonance imaging (MRI), and preserved ejection fraction (a measurement of the pumping activity from the heart). The patients received orally either 25 mg eplerenone (20 individuals) or placebo (22 individuals), besides their usual therapy with angiotensin receptor blockers (ARB) or angiotensin-converting enzyme (ACE) inhibitors. The drug/placebo was administered in a single setting every other day for one month, followed by an increase to once daily if the patient maintained normal levels of potassium. Follow-up appointments were performed at 6 and 12 months, including a cardiac MRI exam.

Researchers found that after 12 months, the combination of eplerenone with the ARB or ACE inhibitors therapy resulted in a smaller decrease in left ventricular systolic function (contractile function) in comparison with patients who received the placebo. Interestingly, in patients taking eplerenone, a significant decrease in the decline in cardiac function was only observed after at least 6 months of therapy.

“Our findings suggest that early treatment with eplerenone attenuates decline in cardiac function, which is a leading cause of death in Duchenne muscular dystrophy,” wrote the research team. “Although the fundamental goal of this study was to test the use of early intervention with available drugs in a disorder in which patients are likely to have progressive cardiomyopathy, the need for long-term clinical follow-up is apparent when recognizing that hard events, such as cardiac failure and death, are unlikely to occur for many more years.”

It is possible to access more information about this trial in the website ClinicalTrials.gov, under the code number NCT01521546.