Role of transthoracic echocardiography in the estimation of coronary sinus blood flow in coronary artery disease.

BACKGROUND

Coronary sinus blood flow (CSBF) is reduced in coronary artery disease (CAD).

OBJECTIVE

To evaluate the usefulness of transthoracic echocardiography (TTE) in assessing CSBF in patients with CAD.

METHODS AND RESULTS

232 patients with CAD, including 28 patients with acute myocardial infarction (AMI) (thrombolysed), 80 patients with unstable angina and delayed presentation MI, 80 patients admitted for coronary angiography (CAG) and 44 patients awaiting percutaneous transluminal coronary angioplasty (PTCA) were evaluated with TTE to obtain CSBF values; results were compared with those of controls. In the CAG group, the correlation between CSBF and lesion severity was assessed while in the thrombolysis and PTCA groups, CSBF levels before and after treatment were evaluated. The control group had a coronary sinus diameter of 8.73±2.08 mm and mean CSBF of 441±172 mL/min. Both the diameter and mean CSBF levels were reduced in patients with CAD. In the AMI group, patients with anterior wall myocardial infarction (AWMI) showed a greater percentage increase in CSBF after thrombolysis than patients with inferior wall myocardial infarction (IWMI). In the CAG group, patients with lower CSBF values (<300 mL/min) had more multivessel involvement, especially in patients with AWMI than in those with IWMI. In the PTCA group, patients with AWMI with initial CSBF levels <300 mL/min had a greater percentage increase in CSBF levels after stenting than patients with AWMI with CSBF values >300 mL/min.

CONCLUSIONS

Non-invasive assessment of CSBF by TTE is a simple, cost-effective, imaging modality in patients with CAD, especially for risk stratification and assessing therapeutic success.