Postsystolic shortening (PSS) by speckle-tracking echocardiography (STE) is a marker of myocardial ischemia and may improve diagnostic strategy. We sought to evaluate if PSS is associated with the coronary artery calcium score (CACS) and stenosis by computed tomography angiography (CTA) in patients with suspected stable angina pectoris (SAP). We retrospectively studied 437 SAP patients (age 58 ± 11 years, 41% male) who underwent STE, evaluation of CACS and assessment of significant stenosis (≥ 50%) by CTA. The postsystolic index (PSI) was defined as follows: 100x([peak negative strain cardiac cycle - peak negative strain systole])/peak negative strain cardiac cycle. A wall had PSS if any segment within the wall had a PSI ≥ 20%. We defined categories for walls with PSS: 0, 1, 2 and ≥ 3, and CACS: 0, 1-100, 101-400 and > 400. Each additional wall with PSS was associated with a 43% relative increase in CACS (95%CI +9% to +87%, P = 0.010), while each 1% absolute increase in the PSI was associated with a 9% relative increase in CACS (95%CI +1% to +18%, P = 0.031). Walls with PSS (OR 1.81 per 1 wall increase, 95%CI 1.27-2.59, P = 0.001) and the PSI (OR 1.12 per 1% increase, 95%CI 1.04-1.21, P = 0.004) were associated with the occurrence of CACS > 400. Additionally, walls with PSS (OR 1.53 per 1 wall increase, 95%CI 1.21-1.93, P < 0.001) was a predictor of significant stenosis by CTA. PSS is associated with CACS and significant stenosis by CTA in patients with SAP and may aid in the selection of patients referred for cardiac computed tomography.
Keywords: Coronary artery calcium; Echocardiography; Postsystolic shortening; Stable angina.