Resting multilayer 2D speckle-tracking TTE for detection of ischemic segments confirmed by invasive FFR part-2, using post-systolic-strain-index and time from aortic-valve-closure to regional peak longitudinal-strain

- To identify LV segments ± FFR ≤ 0.80, the area under ROC curve was 0.58 for PSI.
- The area under ROC curve was 0.57 for the time interval between AVC and regional PLS.
- PSI enabled the identification of LV segments with FFR ≤ 0.80 with thresholds of 12%.
- Time interval between AVC and PLS identified LV segments with FFR ≤ 0.80 with 88 ms.
- But both areas under ROC curves were not statistically significant.

PurposeThis study evaluated the post-systolic strain index (PSI), and the time interval between aortic valve closure (AVC) and regional peak longitudinal strain (PLS), measured by transthoracic echocardiography (TTE), for detection of left ventricular (LV) myocardial ischemic segments confirmed by invasive fractional flow reserve (FFR).Materials and methods39 stable patients (32 males; 65.8 ± 11.9 years) with 46 coronary arteries at ≥ 50% stenosis on invasive coronary angiography underwent 2D speckle tracking TTE (Vivid E9, GE Healthcare) and invasive FFR measurements. PSI, AVC and regional PLS in each LV segment were calculated.ResultsFFR ≤ 0.80 was detected in 27 LV segments. There were no significant differences between segments supplied by FFR ≤ 0.80 and FFR > 0.80 vessels in either PSI or the time interval between AVC and regional PLS. To identify LV segments ± FFR ≤ 0.80, the receiver operator characteristic (ROC) curves for PSI, and the time interval between AVC and regional PLS had areas under the curve (AUC) values of 0.58 and 0.57, respectively, with best cut-off points of 12% (sensitivity 70.4%, specificity 57.9%) and 88 ms (sensitivity 70.4%, specificity 52.6%), respectively, but the AUCs were not statistically significant.ConclusionIn stable coronary artery disease patients with ≥ 50% coronary artery stenosis, measurement of PSI, and the time interval between AVC and regional PLS, on resting TTE, enabled the identification of LV segments with FFR ≤ 0.80 using each appropriate threshold for PSI, and the time interval between AVC and regional PLS, with reasonable diagnostic accuracy. However, the AUC values were not statistically significant.