Long-Term Prognostic Value of Simultaneous Assessment of Atherosclerosis and Ischemia in Patients with Suspected Angina: Implications for Routine Use of Carotid Ultrasound during Stress Echocardiography

Abstract

Background: While the impact of carotid plaque on cardiovascular events is well investigated in asymptomatic epidemiologic studies, the long-term clinical impact of carotid plaque and its burden (CPB) in patients with new-onset suspected stable angina with no history of coronary artery disease beyond stress echocardiography (SE) is not known. We sought to investigate this with a prospective study, where patients were followed up for adverse events.

Methods: Consecutive patients referred for SE underwent simultaneous carotid ultrasonography to assess CPB, defined as the total number of carotid plaques per patient. Stress echocardiography was reported off-line using a 17-segments model and four-point wall thickening scoring. Peak wall thickening scoring index was the sum of scores of each segment divided by 17.

Results: Of the 592 patients, 573 (age 59 ± 11, 45% male) had follow-up data. During a mean of 7.2 years, 85 patients had a first major adverse event (all-cause mortality and acute myocardial infarction: 68 had hard events and 17 had unplanned revascularization). On multivariate Cox regression analysis, pretest probability of coronary artery disease (P = .048), peak wall thickening scoring index (P < .0001), and CPB (P < .0001) predicted major adverse events; however, only CPB retained significance for both hard events and hard cardiac events (P = .001 and < .0001, respectively). Major adverse events and hard events were the least in patients with normal SE and absent carotid plaque (annualized event rate: 1.1% and 1.02%, respectively), with a significant increase in normal SE and carotid plaque disease (2.4% and 2.05%, P = .004 and P = .01, respectively). The presence of plaque did not have an impact on these outcomes in an abnormal SE cohort.

Conclusions: In patients with suspected stable angina with no history of cardiovascular disease, carotid atherosclerosis and myocardial ischemia detected by ultrasound provided synergistic information for the long-term prediction of events, but atherosclerosis predicted hard events beyond myocardial ischemia, particularly in patients with a normal SE.

Keywords: Carotid plaque; Coronary artery disease; Pretest probability of coronary artery disease; Stress echocardiography.