Clinical Impact of the Ankle-Brachial Index in Patients Undergoing Successful Percutaneous Coronary Intervention

Several studies have reported a relationship between clinical outcomes and the ankle-brachial index (ABI) in different populations. However, the relationship in Japanese patients or in patients undergoing percutaneous coronary intervention (PCI) has not been examined well.

The subjects were 1,857 patients who underwent PCI from July 2007 to May 2010 and in whom the carotid and renal arteries and abdominal aorta were examined simultaneously by ultrasonography and ABI. We investigated the relationship between ABI and major adverse cardiovascular events (MACE: all-cause death, myocardial infarction, and stroke). The median follow-up was 1,322 days (interquartile range: 1,092-1,566 days). Patients with low (<0.9), borderline (0.9-1.0) and high ABI (>1.4) had significantly higher incidence of MACE at 4 years (31%, 15%, 10%, and 29% for the low, borderline, normal, and high groups, respectively; log-rank P<0.0001) and all-cause mortality at 4 years (22%, 12%, 6.9%, and 29%, respectively; P<0.0001) compared with the normal ABI group (1.0≤ABI≤1.4). The adjusted hazard ratios for MACE were 2.35 (1.72-3.20), 1.27 (0.89-1.80) and 1.87 (0.81-3.79) for low, borderline and high ABI, respectively.

This study suggested that ABI provides additional information for cardiovascular disease risk stratification in Japanese patients undergoing PCI, even it is borderline ABI.