Abstract 15249: Diagnostic Utility of Coronary Flow Velocity Reserve by Transthoracic Doppler Echocardiography in Comparison to 320-row Multidetector Computed Tomography Coronary Angiography in the Assessment of In-Stent Restenosis in the Left Anterior Descending Coronary Artery
We sought to determine the feasibility and diagnostic accuracy of coronary flow velocity reserve (CFVR) using transthoracic doppler echocardiography by comparing 320-row multidetector computed tomography coronary angiography (CTCA) for predicting binary in-stent restenosis. Eighty-nine patients (67 ± 9 years, 60 male) with 137 implanted coronary stents in the LAD were enrolled in this study. Labeled stent diameters were distributed as follows: 2.5mm (n=46), 2.75mm (n=1), 3.0mm (n=63), 3.5mm (n=25), and 4.0mm (n=2). Overlapping stents were considered to represent a single stent; accordingly a total of 119 stented segments in 89 LAD were assessed. An invasive coronary angiography was performed in all patients within 2 weeks after transthoracic doppler echocardiography and CTCA. Coronary flow velocities were recorded in the distal LAD by transthoracic doppler echocardiography at rest and during hyperemia induced by intravenous infusion of adenosine triphosphate (0.14 mg/kg/min). CFVR was calculated as the ratio of hyperemic to basal peak and mean diastolic velocity and CFVR<2 was considered >70% stenosis. Retrospectively electrocardiographically-gated CTCA was performed with the use of automatic bolus-tracking Methods. Stents were viewed and narrowing of the stented segment was graded 1 to 4 according to the proportion of the vessel lumen that was poorly enhanced: grade 4 was considered >70% stenosis. In-stent restenosis (>70% luminal narrowing) by quantitative coronary angiography was found in 10 (9.8%) of the stent segments. CFVR was successfully measured in 87 of 89 LAD (97.8%) whereas only 105 in 119 stents (88.2%) by CACT. CFVR<2 had a sensitivity of 88.9%, a specificity of 98.7%, a positive predictive value of 88.9%, and a negative predictive value of 98.7% for predicting in-stent restenosis. CTCA grade 4 had a sensitivity of 66.7%, a specificity of 98.5%, a positive predictive value of 85.7%, and a negative predictive value of 94.7% for predicting in-stent restenosis. In Conclusions, in-stent restenosis was diagnosed with high feasibility and high accuracy using transthoracic doppler echocardiography, which implies a significant role for CFVR in identifying in-stent restenosis in the LAD.
- © 2010 by American Heart Association, Inc.