Usefulness of Postsystolic Shortening to Diagnose Coronary Artery Disease and Predict Future Cardiovascular Events in Stable Angina Pectoris

BACKGROUND: Postsystolic shortening (PSS) may occur during myocardial ischemia. We aimed to assess the diagnostic and prognostic potential of PSS in patients with suspected stable angina pectoris (SAP).

METHODS: This is a prospective study of patients with suspected SAP (N = 293), no prior cardiac history, and normal ejection fraction, who were examined by speckle-tracking echocardiography, coronary angiography, and exercise electrocardiogram. We excluded patients with known heart disease (ischemia, heart failure, valve disease), bundle branch block, pathological Q-waves, and arrhythmias. PSS was assessed using the postsystolic index (PSI), and categorical presence of PSS was defined as PSI ≥ 20% in one myocardial wall. The primary end point was major adverse cardiovascular events (MACEs), a composite of incident heart failure, myocardial infarction, and stroke. The secondary end point was MACE and revascularization (percutaneous coronary intervention/coronary artery bypass graft).

RESULTS: A stenosis ≥70% in one or more coronary arteries defined significant coronary artery disease (CAD; n = 107). Patients with significant CAD had a higher prevalence of PSS (55% vs 39%; P < .002), and presence of PSS was an independent predictor of significant CAD in multivariable models adjusted for clinical data, exercise test, and echocardiographic measures (odds ratio, 2.45; 95% CI, 1.08-5.60; P = .033). The PSI confirmed this association (odds ratio, 1.71; 95% CI, 1.04-2.82; P = .034 per 1% increase). During median follow-up of 3.5 years (interquartile range, 2.7, 4.1) a total of 25 patients (8.5%) experienced MACE and 46 (15.7%) had the secondary end point. Presence of PSS was a predictor of MACE (hazard ratio, 2.57; 95% CI, 1.12-5.95; P = .028), and the association remained significant in adjusted models. Both presence of PSS and PSI were independent predictors of the secondary end point.

CONCLUSIONS: In patients with suspected SAP, presence of PSS provides independent diagnostic information on significant CAD and offers novel prognostic information regarding risk of future cardiovascular events.