ARB offers no benefit over beta-blockers for Marfan’s patients

For patients with Marfan’s syndrome, losartan may not be any better at reducing rates of aortic-root enlargement than beta-blockers. The results challenge prior studies that suggested losartan may have an advantage over beta-blocker therapy.

Researchers in the Pediatric Heart Network enrolled 608 Marfan’s syndrome patients between the ages of six months and 25 years old for this study. Patients were randomly assigned the ARB losartan (Cozaar, Merck) or atenolol (Tenormin, AstraZeneca). Over a three-year period, Ronald V. Lacro, MD, of Boston Children’s Hospital, and colleagues followed outcomes and vital statistics in these patients at intervals of six, 12, 24, and 36 months from baseline. At each follow-up, aortic-root diameter was measured by echocardiogram.

Patients were fairly good about taking their medications: 73 percent and 69 percent of patients took at least 80 percent of their dispensed dose for atenolol and losartan, respectively.

However, they noted few differences between the two groups in outcomes, with insufficient evidence as to a differential treatment effect. Patients given atenolol had a “small but significant difference” in their favor in the absolute diameter and aortic annulus z score, they noted.

They also found that treatment of both types resulted in a greater reduction in aortic-root z scores between younger vs. older participants, suggesting an improved trajectory with earlier treatment.

Lacro et al noted that the beta-blocker dose used was higher than in other studies, which may have had some effect on the outcomes.

An editorial commentary from Juan M. Bowen, MD, and Heidi M. Connolly, MD, from the Mayo Clinic in Rochester, Minn., wrote that these findings would stimulate conversations among physicians treating Marfan’s. While they wrote that the findings were positive for continuing beta-blocker treatment for aortic protection in these patients, “Losartan appears to be a reasonable treatment option, especially in patients who cannot take beta-blockers.”

The findings were published online Nov. 18 in the New England Journal of Medicine and presented simultaneously at the American Heart Association scientific session in Chicago.