There is no consensus on when to initiate cardioprotective treatment in patients with Becker muscular dystrophy (BMD), and practice varies widely. A new study published in the Journal of Neuromuscular Diseases concludes that starting treatment with an ACE inhibitor once heart function falls below the lower limit of normal reduces the risk of patients developing severe cardiomyopathy and develop heart failure, which are common episodes in BMD. are .
Prevention of end-stage heart failure, one of the leading causes of death in patients with BMD, is the focus of their treatment. BMD is a form of muscular dystrophy that is related to Duchenne muscular dystrophy (DMD) as both result from a mutation in the dystrophin gene, but with a milder course in the case of BMD. The latest American College of Cardiology / American Heart Association practice guidelines recommend prescribing an angiotensin converting enzyme inhibitor (ACE-i) for patients with non-ischemic cardiomyopathy when the left ventricular ejection fraction (LVEF) falls below 40%. However, there is no consensus on when to start treatment in patients with BMD.
“While there is ample literature showing beneficial effects of cardioprotective treatments such as ACE inhibitors in DMD, there has been limited evidence to date of a similar effect in BMD,” said lead researcher Karim Wahbi, MD, PhD, AP-HP , Myology Institute; Cochin Hospital; University of Paris; and Inserm, UMRS, Paris, France. “As a result, there is no consensus among experts in the field of neuromuscular cardiomyopathies. And there remains a great variability in the use of ACE inhibitors in BMD from one country to another and from one center to another initiated when the heart function is normal, as in DMD? Or if there is overt heart failure (left ventricular ejection less than 40%), as recommended in the general population? Or somewhere in between? We wanted to close this gap. “
The researchers wanted to determine whether starting treatment with an ACE inhibitor earlier than recommended by clinical practice guidelines would improve long-term cardiac outcomes in patients with BMD. They retrospectively analyzed data from 183 patients who were registered in a French multicenter BMD registry between January 1990 and April 2019, using a complex statistical analysis, the so-called propensity score analysis. They found that long-term cardiac outcomes in patients with BMD were significantly better when treatment with an ACE inhibitor was introduced earlier than recommended in current practice guidelines.
Of patients with early treatment (LVEF less than 50%) versus conventional treatment (LVEF less than 40%), less than 4% were hospitalized for heart failure treatment, compared with 11.8% who those treated conventionally, and 17.6% versus 29.4% had a decrease in LVEF of less than 35%.
The benefits of ACE inhibitors in this study in patients with BMD are similar to those seen in a previous randomized study in patients with DMD, demonstrating their high effectiveness in preventing myocardial dysfunction, especially when used early in the course of the disease .
“This is the first study to show that treatment with an ACE inhibitor in patients with BMD can be beneficial for long-term heart health and reduce the risk of severe cardiomyopathy and heart failure The limit of the normal range is falling, “says Dr. Wahbi. We hope that these results will lead to greater and earlier use of ACE inhibitors in patients with BMD worldwide.”
Stalens, C., et al. (2021) Improved cardiac outcomes through early treatment with angiotensin-converting enzyme inhibitors in Becker muscular dystrophy. Journal of Neuromuscular Diseases. doi.org/10.3233/JND-200620.