Diagnostic value of post systolic shortening in myocardial ischemia
I Ellouz, S Antit, M A Mahfoudhi, E Boussabah, L ZakhamaAbstract
Introduction
Reduced coronary blood causes metabolic changes, followed by diastolic then systolic dysfunction, electrical abnormalities and finally chest pain, "the ischemic cascade". Echocardiography allows early detection of functional alterations: wall motion abnormalities, strain alteration, and post systolic shortening (PSS). PSS is myocardial shortening after end-systole, seen in regions with contractile dysfunction.
Purpose
This study aimed to investigate the association between post-systolic shortening (PSS) and coronary artery disease (CAD).
Methods
We conducted a prospective monocentric study at our Cardiology Department. Eligible patients had stable angina, unstable angina, or non-ST-elevation myocardial infarction (NSTEMI) and were scheduled for coronary angiography as part of their clinical management. A comprehensive echocardiogram was performed before coronary angiography. Patients were divided into two groups: 37 with CAD (G1), 24 without CAD (G2).
Results
We included 61 patients with a mean age of 57 ± 10 years, with 68% male. Acute coronary syndrome was the main indication for angiography. Significant stenosis affected the left anterior descending artery in 52%, 23% the circumflex artery in 23%, the right artery in 21%. Among CAD patients, 18 presented PSS. PSS showed 95% sensitivity and 54% specificity (p<0.001). The median post-systolic index (PSI) was 2.47 (1.04- 4.05) and was significantly associated with CAD (AUC=0.765, p=0.001). The number of walls exhibiting pathological PSS was also a significant predictor, yielding an AUC of 0.754 (p = 0.001). Optimal threshold were >2.17 for mean PSI, providing a sensitivity of 81.8% and specificity of 70.8% (p < 0.0001), and ≥0.5 for the number of walls with pathological PSS, yielding a sensitivity of 54.1% and specificity of 95.8% (p = 0.001, Youden index = 0.541). Left Ventricle Ejection Fraction and Global Longitudinal Strain demonstrated a poor discriminative capacity (respectively: AUC 0.532, p = 0.674; AUC 0,394, p=0,163). PSS has not showed localizing value in ischemic myocardial segments. In multivariate analysis, the number of walls with pathological PSS was the only independent predictor (OR = 12.87, 95% CI: 1.89–91.59, p = 0.011).
Conclusion
PSS showed high sensitivity but limited specificity, quantitative assessment, particularly the number of left ventricular walls with pathological PSS, proved to be the strongest and only independent predictor of CAD.PSI = 0For image description, please refer to the figure legend and surrounding text.ROC CURVEFor image description, please refer to the figure legend and surrounding text.