Duchenne Muscular Dystrophy: Cardiomyopathy

Cardiac abnormalities are a significant cause of death and morbidity in patients with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), especially as boys with DMD are now living through their twenties. The clinical course of cardiomyopathy – progressive decline in left ventricular function resulting in cardiac failure – is usually prolonged, though sudden death from arrhythmia may occur. Many patients do not show symptoms of cardiomyopathy due to their lack of physical activity, but early changes in cardiac function are usually apparent on cardiac imaging studies, e.g., echocardiogram or cardiac magnetic resonance imaging (MRI).
Because changes in cardiac function are uncommon before the second decade of life, the Treat-NMD standards, [Birnkrant: 2018], recommend a cardiology evaluation with an echocardiogram and electrocardiogram (ECG) at the time of diagnosis every 2 years until age 10 and then annually unless progressive problems suggest the need for more frequent exams. [Feingold: 2017] cardiology referral is also recommended before any major surgery. When present, clinical symptoms may include those associated with congestive heart failure (edema, shortness of breath, orthopnea), reduced cardiac output (especially fatigue), and/or arrhythmias. However, symptoms might be absent, due to decreased skeletal muscle strength and decreased physical activity, until very late in the course of the disease. With severe cardiomyopathy, thromboembolic events have been observed.
Some cardiologists may order a cardiac MRI, instead of or in addition to ECG/echocardiogram, for better anatomical visualization. Cardiac MRI may show evidence of heart muscle scarring that cannot be seen via echocardiogram. Decreased left ventricular ejection fraction on echocardiogram is the most common early finding of dilated cardiomyopathy.
Early diagnosis and treatment of dilated cardiomyopathy, based on echocardiographic findings and not clinical deterioration, are advised. Initial medication options include angiotensin converting enzyme (ACE) inhibitors, such as enalapril or lisinopril, and angiotensin receptor blockers (ARBs), such as losartan. Some clinicians will start these medications at age 10, even before detection of reduced ejection fraction. The 2017 American Heart Association guidelines for the treatment of cardiac problems in children with neuromuscular disease include this approach as “may be considered.” [Feingold: 2017]
These medications are also commonly used to treat high blood pressure, which may be related to prolonged steroid exposure in boys with DMD. Other agents, such as beta-blockers, may be added in the setting of advanced dilated cardiomyopathy depending on cardiology preference and disease manifestations. Other medications, such as diuretics, may be added when a patient has signs or symptoms of congestive heart failure. Anti-arrhythmic therapy is sometimes needed as well. Left ventricular assist devices (LVADs) may be increasingly offered to boys in heart failure. In some cases, cardiac transplantation may be a possibility, although this varies with the site where the child is receiving care. There is also recent evidence suggesting that prolonged steroid therapy may help delay the onset of cardiomyopathy. [Schram: 2013]
Of note, the mothers of boys with DMD/BMD may also be at risk for cardiac problems. They should be evaluated by genetic testing to confirm carrier status and if positive, evaluation, and monitoring by a cardiologist.

Resources

Practice Guidelines

TREAT-NMD, a neuromuscular network, has published a list of expert guidelines, including cardiology recommendations:

Birnkrant DJ, Bushby K, Bann CM, Alman BA, Apkon SD, Blackwell A, Case LE, Cripe L, Hadjiyannakis S, Olson AK, Sheehan DW, Bolen J, Weber DR, Ward LM.
Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management.
Lancet Neurol. 2018;17(4):347-361. PubMed abstract / Full Text

Birnkrant DJ, Bushby K, Bann CM, Apkon SD, Blackwell A, Brumbaugh D, Case LE, Clemens PR, Hadjiyannakis S, Pandya S, Street N, Tomezsko J, Wagner KR, Ward LM, Weber DR.
Diagnosis and management of Duchenne muscular dystrophy, part 1: diagnosis, and neuromuscular, rehabilitation, endocrine, and gastrointestinal and nutritional management.
Lancet Neurol. 2018;17(3):251-267. PubMed abstract / Full Text

Birnkrant DJ, Bushby K, Bann CM, Apkon SD, Blackwell A, Colvin MK, Cripe L, Herron AR, Kennedy A, Kinnett K, Naprawa J, Noritz G, Poysky J, Street N, Trout CJ, Weber DR, Ward LM.
Diagnosis and management of Duchenne muscular dystrophy, part 3: primary care, emergency management, psychosocial care, and transitions of care across the lifespan.
Lancet Neurol. 2018;17(5):445-455. PubMed abstract / Full Text

Helpful Articles

McNally EM, Kaltman JR, Benson DW, Canter CE, Cripe LH, Duan D, Finder JD, Groh WJ, Hoffman EP, Judge DP, Kertesz N, Kinnett K, Kirsch R, Metzger JM, Pearson GD, Rafael-Fortney JA, Raman SV, Spurney CF, Targum SL, Wagner KR, Markham LW.
Contemporary cardiac issues in Duchenne muscular dystrophy. Working Group of the National Heart, Lung, and Blood Institute in collaboration with Parent Project Muscular Dystrophy.
Circulation. 2015;131(18):1590-8. PubMed abstract / Full Text

Angelini C.
Prevention of cardiomyopathy in Duchenne muscular dystrophy.
Lancet Neurol. 2015;14(2):127-8. PubMed abstract

Raman SV, Hor KN, Mazur W, Halnon NJ, Kissel JT, He X, Tran T, Smart S, McCarthy B, Taylor MD, Jefferies JL, Rafael-Fortney JA, Lowe J, Roble SL, Cripe LH.
Eplerenone for early cardiomyopathy in Duchenne muscular dystrophy: a randomised, double-blind, placebo-controlled trial.
Lancet Neurol. 2015;14(2):153-61. PubMed abstract / Full Text

Leung DG, Herzka DA, Thompson WR, He B, Bibat G, Tennekoon G, Russell SD, Schuleri KH, Lardo AC, Kass DA, Thompson RE, Judge DP, Wagner KR.
Sildenafil does not improve cardiomyopathy in Duchenne/Becker muscular dystrophy.
Ann Neurol. 2014;76(4):541-9. PubMed abstract / Full Text

Iodice F, Testa G, Averardi M, Brancaccio G, Amodeo A, Cogo P.
Implantation of a left ventricular assist device as a destination therapy in Duchenne muscular dystrophy patients with end stage cardiac failure: management and lessons learned.
Neuromuscul Disord. 2015;25(1):19-23. PubMed abstract

Authors & Reviewers

Initial publication: September 2013; last update/revision: January 2020
Current Authors and Reviewers:
Authors: Richard Williams, MD
Lynne M. Kerr, MD, PhD
Authoring history
2017: update: Meghan Candee, MDA
2013: first version: Richard Williams, MDA; Lynne M. Kerr, MD, PhDA
AAuthor; CAContributing Author; SASenior Author; RReviewer

Page Bibliography

Birnkrant DJ, Bushby K, Bann CM, Alman BA, Apkon SD, Blackwell A, Case LE, Cripe L, Hadjiyannakis S, Olson AK, Sheehan DW, Bolen J, Weber DR, Ward LM.
Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management.
Lancet Neurol. 2018;17(4):347-361. PubMed abstract / Full Text

Feingold B, Mahle WT, Auerbach S, Clemens P, Domenighetti AA, Jefferies JL, Judge DP, Lal AK, Markham LW, Parks WJ, Tsuda T, Wang PJ, Yoo SJ.
Management of Cardiac Involvement Associated With Neuromuscular Diseases: A Scientific Statement From the American Heart Association.
Circulation. 2017;136(13):e200-e231. PubMed abstract

Schram G, Fournier A, Leduc H, Dahdah N, Therien J, Vanasse M, Khairy P.
All-cause mortality and cardiovascular outcomes with prophylactic steroid therapy in Duchenne muscular dystrophy.
J Am Coll Cardiol. 2013;61(9):948-54. PubMed abstract