PAD Plaque Rupture Studied

February 20, 2010—A study of the incidence and predictors of plaque rupture in the peripheral arteries was published by Hiroyuki Okura, MD, et al in Circulation: Cardiovascular Interventions (2010;3:63–70). The investigators hypothesized that plaque rupture may be present in the peripheral arteries of the patients at high risk for cardiovascular events and is possibly associated with vascular vulnerability.

The investigators studied 101 iliofemoral arteries from 101 patients undergoing angioplasty. Intravascular ultrasound imaging was performed before intervention. Plaque rupture was defined as presence of a cavity that communicated with the lumen with an overlying residual fibrous cap fragment. Incidence, numbers, and location of the plaque rupture were investigated. Plaque rupture was found in 42 of 101 arteries (42%). Patients with plaque rupture had a significantly higher prevalence of acute coronary syndromes than did patients without plaque rupture (42% vs 16%; P = .01). By multivariable logistic regression analysis, acute coronary syndromes (P = .004) and male sex (P = .01) were independent clinical correlates of plaque rupture. During follow-up (median, 14.7 months), the incidence of major adverse cardiac or cerebrovascular events (death, myocardial infarction, and ischemic stroke) was similar between the two groups.

As reported by the investigators, the incidence of major adverse cardiac or cerebrovascular events plus peripheral vascular events (unplanned vascular intervention and amputation) was significantly higher in patients with plaque rupture than in patients without plaque rupture (46% vs 21%; P = .008). By multivariable Cox regression analysis, plaque rupture (hazard ratio, 2.8; 95% confidence interval, 1.23–6.37; P = .01) and Fontaine stage IV (hazard ratio, 3.5; 95% confidence interval, 1.58–7.71; P = .002) were independent predictors of major adverse cardiac or cerebrovascular events plus peripheral vascular events.

The study demonstrated that ruptured plaque of the iliofemoral arteries is a common finding. Patients with plaque rupture had a higher prevalence of history of acute coronary syndromes and lower major adverse cardiac or cerebrovascular events plus peripheral vascular event-free survival, concluded the investigators.