Assessment of regional wall motion abnormalities using parametric imaging of real time 3D echocardiography compared to 2D echocardiography: validation by coronary angiography

ABSTRACT

Identification and quantification of left ventricular regional wall motion abnormalities [RWMA] on echocardiograms is of paramount clinical importance but is still performed by a subjective visual method. we tried a new tool for assessment of RWMA using parametric [PI] of real time 3D Echocardiography [RT3DE] compared to traditional visual assessment of 2D echo [2DE] and validated by coronary angiography. We studied 100 patients scheduled for coronary angiography based on previous history of myocardial infarction [MI] [STMI or NSTMI]. RWMA was assessed by both conventional 2DE and PI of RT3DE according to the 17 segment left ventricular model of the American Society of Echocardiography [ASE].Coronary angiography was performed for all patients. Coronary artery stenosis was considered significant when luminal narrowing of 70% or more was present. The angiographic data of all patients was used as the gold standard to compare the diagnostic ability of both methods for detection of RWMA. There was a good agreement between PI of RT3DE and 2DE in assessment of RWMA of most [5 of 7] segments supplied by LAD, and all 5 segments supplied by LCX and 3 of 5 segments supplied by RCA. PI of RT3DE showed higher sensitivity than 2DE [60.71% VS 47.32%, p 0.001] for detection of RWMA in significant LAD lesion, while there was no significant difference regarding sensitivity of both methods in detection of RWMA in significant LCX or RCA lesions. [66.33%vs 54.00% p=0.074] and [62.77%vs 53.88%, p=0.140] respectively. There was no significant difference between PI of RT3DE and 2DE specificity for LAD, LCX and RCA lesions. [89.68% vs 90.07% p=0.0865], [87.42% vs 89.14%p=0.063] and [79.06% vs 80.62%, p=0.568] respectively. RT3DE showed higher sensitivity, specificity, positive predictive value and negative predictive than 2DE for detection of RWMA in patients with NSTMI in prescense of significant angiographic lesions. [77.8% vs 44.4, p=0.031], [95% vs 83.% p=0.04],[95% vs 88.8%],[60% vs 33.3%] Respectively. We have shown that PI of RT3DE can be used for assessment of RWMA with good agreement to visual assessment by conventional 2DE with better sensitivity to detect RWMA in segments supplied with LAD .PI also has better sensitivity, specificity, positive predictive value [PPV] and negative predictive value[NPV] than 2DE in patients with NSTMI