Quantitative evaluation of myocardial perfusion in coronary heart disease by myocardial contrast and dobutamine stress echocardiography.

Objective: We aimed to investigate how combining myocardial contrast echocardiography (MCE) with dobutamine stress echocardiography (DSE) could help evaluate myocardial perfusion in coronary heart disease patients and understand changes in microcirculation across different levels of coronary artery blockage.

Methods: We conducted MCE and DSE tests on 53 coronary heart disease patients, categorizing ischemic myocardium into four groups: A (<50%), B (50%-69%), C (70%-89%), and D (≥90%). Dynamic myocardial perfusion images were captured during rest and peak dobutamine stress from various angles, analyzing parameters like plateau value A, slope β, and the product A × β, reflecting different aspects of myocardial blood flow.

Results: Parametric values of myocardial perfusion (PVMPs) were significantly lower in group D at rest compared with other groups (p < 0.001). PVMPs increased notably at peak dobutamine stress in groups A, B, and C (p < 0.001). Groups A and B had higher PVMPs than groups C and D, with group D significantly lower (p < 0.001). β reserve values decreased gradually from group A to D, with significantly lower values of A and A × β in groups C and D compared with A and B (p < 0.001). Sensitivity and specificity for predicting >70% coronary artery blockage was 80%, 66%, and 74%, 80%, respectively, using specific thresholds.

Conclusion: Combining MCE with DSE is highly sensitive and accurate in diagnosing obstructive coronary artery blockages. It also helps assess myocardial microcirculation perfusion and left ventricular reserve function, which decline with increasing severity of coronary artery blockage.