Morphologic and physiologic validation of quantitative coronary arteriography utilizing digital methods

To assess the in-vivo performance of a coronary quantitation program, 16 dogs were instrumented with precision-drilled, plastic cylinders to create intraluminal stenoses ranging from 0.83 mm to 1.83 mm. Biplane, on-line digital coronary angiograms and cineangiograms were obtained. The on-line digital images were analyzed in nonsubtracted and subtracted modes. Cineangiograms were digitized and quantitated by the same computer program. There was an excellent correlation between known and measured minimal diameter stenoses (r = 0.87−0.98, s.e.e. = 0.09−0.24 mm). Inter- and intraobserver variability analysis showed high reproducibility (r = 0.90−0.97, s.e.e. = 0.12−0.23 mm). The best results in both analyses were achieved by nonsubtracted digital imaging and the worst by cineradiography. Measures of percent diameter stenosis, percent area stenosis (geometric and videometric) and absolute minimal cross-sectional area (geometric and videometric) were all highly correlated with independent measures of actual coronary flow reserve. This study provides a direct, in-vivo, anatomical and physiological validation of a new and rapid coronary quantitation method suitable for analysis of both digital angiograms and cineangiograms.