[The value of area strain imaging diastolic index for predicting left anterior descending severe stenosis]

To evaluate the value of locating and defining severe stenosis of left anterior descending (LAD) with area strain imaging diastolic indexes (ASI-DI) derived from three dimensional speckle tracking imaging (3D-STI).

A total of 92 suspected coronary heart disease patients with left ventricular ejection fraction (LVEF) ≥ 50% and without regional wall motion abnormality, who underwent echocardiography before coronary angiography in our department from July 2012 to April 2014, were included in this retrospective study. Patients were divided into three groups by the level of LAD stenosis: severe stenosis group (≥ 75%, n = 36), mild to moderate stenosis group (1%-74%, n = 22) and control group (without coronary artery stenosis, n = 34). Global peak systolic area strain (GPSAS), global ASI-DI (GASI-DI), and ASI-DI of the regional myocardial segments with blood supplied by LAD were measured. Receiver operating curves (ROC) were obtained between ASI-DI and stenosis level of LAD to locate and to find out the optimal segment and cutoff values.

There was no significant difference of GPSAS among serious stenosis group, mild and moderate stenosis group and control group ((-25.2 ± 6.2) % vs. (-20.3 ± 6.6) % vs. (-21.3 ± 8.6) %, P = 0.159). GASI-DI was significantly lower in severe stenosis group than in mild to moderate stenosis group and control group ((-34.3 ± 14.7) vs. (-48.1 ± 13.3) % vs. (-59.4 ± 12.2) %, both P < 0.01). GASI-DI was similar between mild to moderate stenosis group and control group (P = 0.217). The optimal cutoff values of ASI-DI were 40.3% and area under the curve (AUC) were 0.829 in the base anterior segment for detecting proximal severe stenosis of LAD (sensitivity 0.967, specificity 0.651), 38.3% and 0.843 in the middle anteroseptum for detecting mid-distal sever stenosis of LAD (sensitivity 0.967, specificity 0.651).

Patients with severe LAD stenosis can be screened by ASI-DI among patients with LVEF ≥ 50% and without regional wall motion abnormality. The ASI-DI of base anterior segment and middle anteroseptum can be used to locate the proximal and mid-distal sever stenosis of LAD.