Comparison of the Efficacy of Conventional Echocardiographic Parameters in the Diagnosis of Significant Coronary Artery Stenosis

BACKGROUND: For diagnosis of significant coronary artery stenosis, the most accurate parameter among the conventional echocardiographic parameters remains unknown. OBJECTIVES: To assess the diagnostic efficacy of conventional echocardiographic parameters in the diagnosis of significant coronary artery stenosis and their correlation with the percentage of stenosis considering conventional coronary angiography as gold standard. PATIENTS AND METHODS: Seventy eight individuals were included in the study. The three echocardiographic parameters including the coronary sinus flow [flow (mL/minute)], the global left ventricular perfusion by dividing the coronary sinus flow by left ventricular mass [flow/LVM (mL/minute)] and the difference between the left ventricular mass at end diastole and peak systole using area-length calculation methods [LV (d-s) mass A-L] were assessed using receiver operating characteristic (ROC) analysis for their accuracy to distinguish between normal subjects and patients with significant (> 50%) coronary artery disease (CAD). RESULTS: Flow (mL/minute), flow/LVM (mL/minuteg) and LV (d-s) mass A-L all correlated significantly with the percentage of stenosis (r = -0.64, P < 0.001; r = -0.47, P < 0.001; r = -0.56, P < 0.001, respectively). With the use of the percentage of stenosis > 50% as the criteria to distinguish patients with or without CAD, the areas under the ROC curve for flow (mL/minute) were 0.75, while they were 0.57 for flow/LVM (mL/minuteg) and 0.59 for LV (d-s) mass A-L. The percentage of stenosis > 70% was best detected by coronary sinus flow < 198 mL/minute (sensitivity, 81.35%; specificity, 70.37%; positive predictive value, 63.63%; negative predictive value, 86.36% and accuracy, 75%; P < 0.001). CONCLUSIONS: The coronary sinus flow per minute is the most accurate parameter among the three echocardiographic parameters mentioned above for the assessment of significant stenosis of the coronary artery.