INTRACORONARY DOPPLER GUIDE-WIRE VERSUS STRESS SINGLE-PHOTON EMISSIONCOMPUTED TOMOGRAPHIC TL-201 IMAGING IN ASSESSMENT OF INTERMEDIATE CORONARY STENOSES

Objectives, The purpose of this study was to compare measures of coron ary how reserve by an intracoronary Doppler guide wire with results of stress single-photon emission computed tomographic (SPECT) thallium-2 01 imaging in patients with intermediate coronary artery disease (40% to 70% stenosis). Background. Visual assessment of the coronary arteri ogram as a means of predicting the physiologic significance of interme diate coronary stenoses is inaccurate. Coronary how reserve is a relia ble marker of the functional importance of a coronary lesion. The rece nt development of an intracoronary Doppler guide wire permits routine assessment of coronary how reserve distal to coronary artery stenoses. Methods. We prospectively evaluated coronary flow reserve in 30 subje cts with intermediate stenoses using an intracoronary Doppler guide wi re during elective coronary angiography. Patients subsequently underwe nt stress SPECT thallium-201 testing, and the blinded interpretations were correlated. Coronary flow reserve in a control group with normal coronary arteries classified our sample into group 1 (abnormal flow re serve, <2.0) and group 2 (normal flow reserve, greater than or equal t o 2.0). Results. As defined, the coronary flow reserve of 16 vessels i n group 1 was diminished in comparison to that of 19 vessels in group 2 (p = 0.0001). Qualitative and quantitative analysis of stress SPECT thallium-201 images confirmed perfusion defects in 15 of 16 vascular t erritories in group 1 in contrast to 1 of 19 regions in group 2, The s ensitivity, specificity and overall predictive accuracy of Doppler-det ermined coronary flow reserve for stress SPECT thallium 201 results we re 94%, 95% and 94%, respectively. Conclusions. In appropriately selec ted patients with intermediate coronary artery stenoses, Doppler guide wire determination of lesion significance provides equivalent data to those acquired by stress SPECT thallium-201 imaging.