Coronary flow reserve(CFR) is useful physiologic parameter in the assessment of the coronary artery disease. Transesophageal echocardiography is a less invasive method of assessing coronary flow velocity in the proximal portion of left anterior descending artery than by coronary angiography. We compared with coronary angiography and TEE for the measurement of CFR in coronary artery disease patients.

We investigated 20 patients(12 male and 8 female, mean age : 54±11 years) with chest pain for measurement of CFR. CFR and averge peak velocity(APV) were measured at the proximal protion of left anterior descending artery with Doppler guide wire before and during intracoronary arterial injection of 12 µg of adenosine. CFR and diastolic peak velocity (DPV) were measured at the same artery by pulsed sample volume with TEE before and during intravenous infusion of 0.14mg/kg/min of adenosine for 6 min. Significant occlusive disease was defined as > 50% diameter obstruction of a LAD by caliper estimation on angiography.

1) APV of basal and hyperemic state in nonstenotic group with Dopplerwire study were 22.3±, 69.1±20.3cm/sec in nonstenotic group and 24.7±7.4, 48.4±15.7cm/sec in stenotic group, respectively. APV of hyperemic state was lower than nonstenotic group(p<0.05). 2) DPV of basal and hyperemic state in nonstenotic group with TEE were 30.7±8.5, 90.3±41.7cm/sec in nonstenotic group and 31.7±12.5, 62.3±28.34cm/sec in stenotic group,respectively. DPV of hyperemic state was lower than nonstenotic group(p<0.05). 3) CFR with Dopplerwire study and with TEE in nonstenotic group were 2.94±1.21, 3.10±1.23, in stenotic group were 1.97±0.92, 1.96±0.94, respectively. Correlation of CFR by Dopplerwire and by TEE is ralatively good(r=0.88, p<0.05). 4) Mean blood pressure during intracoronary injection and intravenous infusion with adenosine were decreased 14, 11mmHg respectively(p<0.05), but heart rate was not changed significantly in the intracoronary injection group(p>0.05).

The measurement of CFR by TEE may be useful and safe method for the evaluation of coronary artery disease.