The prediction of left main and/or triple-vessel coronary artery disease by tissue doppler-based longitudinal strain and strain-rate imaging

Background: In the absence of evident regional wall motion abnormality (RWMA) at rest, detection of severe coronary artery disease (CAD) usually requires a stress test. Ventricular strain is a more sensitive parameter of myocardial systolic function and may be abnormal in patients with severe CAD. Thus, this study aimed to evaluate the longitudinal strain and strain-rate imaging for prediction of left main (LM) and triple-vessel disease CAD with normal left ventricular ejection fraction (LVEF) and no RMWA.Materials and Methods: Patients included were of stable CAD, unstable angina, or non-ST segment elevation myocardial infarction with LVEF >50% and without RWMA. A thorough echocardiographic evaluation to assess peak systolic longitudinal strain (PSLS) and PSLS rate (PSLSR) in 16 segments of the left ventricle was done. The visual evaluation of percent diameter stenosis of the angiographic lesions was done according to the American Heart Association classification. Patients were grouped into high-risk group (LM or triple-vessel CAD), low-risk group (CAD other than high risk), and normal group (absence of CAD).Results: A total of 86 patients were studied. Of which, 60 were male and 26 were female. The global PSLS and PSLSR were lower in the high-risk group as compared to the other two groups (P < 0.001). The combined basal plus mid-PSLS and PSLSR were lower in the high-risk group (P < 0.001). Receiver operating characteristic curve analysis showed an optimal cutoff value of −17.3% (sensitivity 82% and specificity 80%) for global PSLS and −15.0% (sensitivity 75% and specificity 73%) for basal plus mid-PSLS for detection of high-risk CAD. Similarly, a cutoff value of −0.74 s−1 (sensitivity 82% and specificity 73.6%) for global PSLSR and −0.66 s−1 (sensitivity 85.7% and specificity 86.7%) for basal plus mid-PSLSR were calculated for the prediction of high-risk CAD.Conclusion: The PSLS and PSLSR were lower in patients having high-risk CAD that included LM and triple-vessel disease, even when resting wall motion and LVEF were normal. The study concluded that PSLS and PSLSR are sensitive and specific noninvasive modalities for predicting the possibility of high-risk CAD in the presence of normal LV systolic function and absence of resting RWMA.