Do the benefits of beta-blocker therapy for Marfan syndrome outweigh the harms, as compared to placebo or no treatment?
Marfan syndrome is a hereditary disorder affecting multiple systems in the body. Enlargement of the aorta (the largest blood vessel that carries blood out of the heart) is one of the most common and important features of this disease. It can lead to life-threatening problems, such as aortic dissection, which is a tear in the inner walls of the aorta causing blood to escape into the layers of the aortic wall, accumulate and potentially rupture.
Beta-blockers, a group of drugs used to decrease blood pressure, have been recommended by guidelines as the first line medical treatment of Marfan syndrome. The exact mechanism of action of beta-blockers in Marfan syndrome is not known.
The evidence is current to June 2017.
We included one study of 70 participants aged 12 to 50 years old with Marfan syndrome, who were assigned to either a beta-blocker called propranolol or no treatment for an average duration of 9.3 years in the control (no treatment) group and 10.7 years in the treatment group.
Study funding source
This study was supported by grants from the National Institute of Health, the US Food and Drug Administration, and the National Marfan Foundation.
Key results and conclusions
Propranolol compared to no treatment did not reduce mortality or morbidity, including aortic dissection, aortic regurgitation (leaking of the aortic valve causing reverse blood flow into the heart), heart failure (inability to pump enough blood around the body), and heart surgery. However, it reduced the rate of enlargement of the aortic diameter. Harms have not been fully reported in this study. We judged this trial to have high risk of bias and low-quality evidence. This study provides inadequate evidence to inform people with Marfan syndrome, their families and care-providers.