Blog | Friday, August 16, 2013

QD: News Every Day--Ankle-brachial index may augment CHA2DS2-VASc scores

One-fifth of nonvalvular atrial fibrillation (afib) patients had an ankle-brachial index (ABI) ≤ 0.90, making it a potentially simple and cheap way to detect vascular disease, an Italian study found.

Consecutive adult patients with nonvalvular afib referred to internal medicine wards were enrolled from October 2010 and continued until October 2012. Exclusion criteria included acquired or congenital valvular afib, active cancer, disease with life expectancy less than 3 years, hyperthyroidism and pregnancy.

Results appeared online at the Journal of the American College of Cardiology.

A data and safety monitoring board interrupted enrolment after just more than 2,000 patients enrolled because of a higher than expected prevalence of low ABIs.

Among afib patients, 428 (21%) had ABI ≤ 0.90 compared to 1,381 (69%) patients, who had an ABI between 0.91 and 1.39. There were 204 (10%) patients who had an ABI ≥ 1.40. (Some patients were excluded for having ABI recorded only in one leg.)

Nonvalvular afib patients with ABI ≤ 0.90 had a higher percentage of CHA2DS2-VASc score ≥ 2 compared to those with ABI > 0.90 (93% vs. 82%;P<0.0001). And, researchers noted, vascular disease assessed by the history elements of CHA2DS2VASc score was present in 17.3% of patients. Including ABI ≤ 0.90 in the definition of vascular disease yielded a total prevalence of 33%.

“Inclusion of ABI ≤ 0.90 in the CHA2DS2-VASc score allowed us better defining of the risk profile of nonvalvular afib patients with an up-grading of the risk score in each CHA2DS2-VASc score category,” the researchers wrote. “This may have important therapeutic implications if the new score could be tested prospectively, as a higher number of [nonvalvular afib] patients would be potentially candidates for an anticoagulant treatment by measuring ABI.”