Transesophageal versus intracoronary Doppler measurements for calculation of coronary flow reserve1.

Objective: The present study was performed to compare coronary flow reserve by transesophageal Doppler echocardiography and intracoronary Doppler flow wire measurements in patients with LAD disease. Methods: 17 patients with various degree of LAD stenosis were studied. Intracoronary LAD Doppler measurements were performed at baseline and after intracoronary injection of 18 μg adenosine. Transesophageal coronary sinus and LAD Doppler measurements were performed at baseline and after intravenous dipyridamole (0.6 mg/kg/5 min). Coronary flow reserve was calculated as the ratio of hyperemic to baseline average peak velocities. Results: Coronary flow reserve was 2.44±0.62 and 2.19±0.76 for proximal and distal intracoronary measurements and was 2.25±0.64 and 1.74±0.63 for transesophageal LAD- and coronary sinus measurements. Proximal intracoronary flow reserve significantly correlated with transesophageal coronary sinus (r = 0.73, p≤0.001) and LAD (r = 0.70, p≤0.005) measurements, whereas distal intracoronary flow reserve only correlated with transesophageal coronary sinus flow reserve (r = 0.56, p≤0.02). Receiver operating characteristic curve analysis demonstrated similar diagnostic accuracy of all applied techniques for detection of a significant LAD stenosis. Conclusions: Coronary flow reserve by both transesophageal techniques correlated with intracoronary Doppler flow wire measurements, however considerable discrepancies may occur in the individual patient. [ABSTRACT FROM PUBLISHER]