November 18th, 2014
Losartan No Better Than Atenolol in Marfan’s Syndrome
Beta-blockers have been the standard treatment for people with Marfan’s syndrome, a rare inherited connective tissue disorder that affects about 1 in 5000 people. The goal of treatment is to prevent or slow down the dilation of the aorta and avoid aortic dissection, the main cause of death. In recent years, studies have raised the hope that losartan, an angiotensin receptor blocker, might be more effective than beta-blockers in slowing aortic enlargement.
The Pediatric Heart Network Investigators randomized 608 children and young adults with Marfan’s syndrome to the beta-blocker atenolol or losartan. After 3 years of follow-up, they reported no significant difference between the two groups in a measurement of aortic-root growth. There were also no differences between the groups in the rates of aortic surgery, aortic dissection, or death. Results of the trial were presented at the American Heart Association meeting in Chicago and published simultaneously in the New England Journal of Medicine.
One finding of potential importance was that the rate of aortic growth decreased more in younger patients in both treatment groups. “This finding suggests that there is merit in starting therapy at a younger age and at an earlier stage of the disease,” said Ronald Lacro, the principal investigator of the study.
John Elefteriades was the discussant of the trial at the AHA meeting. He said it was unlikely that the trial result was a false-negative, since it enrolled enough patients, gave a sufficient dose of the study drugs, and followed patients for a long enough time. He said that the “therapeutic quiver is not completely empty,” though, as early studies raise the hope that statins may be useful in this condition.
In the accompanying editorial in NEJM, Juan Bowen and Heidi Connolly advise that clinicians “should continue to consider beta-blockers to be the primary medical therapy for aortic protection in Marfan’s syndrome. Losartan appears to be a reasonable treatment option, especially in patients who cannot take beta-blockers.”