Value and limitations of computer analysis of digital subtraction angiography in the assessment of coronary flow reserve.

摘要: Conventional coronary angiography has significant limitations in quantifying the severity and functional significance of stenoses. However, reactive hyperemia is an excellent physiologic indicator reserve. Digital subtraction offers potential to analyze blood flow dynamics quantitatively. Therefore we assessed accuracy digital angiographic methods detect quantify reductions reserve secondary stenoses varying magnitude experimental canine preparation. Studies were performed nine anesthetized open-chest dogs with electromagnetic (EMF) probe two pneumatic occluders positioned on left circumflex artery. One occluder served induce by temporary total occlusion, while other produce variable gradations stenosis. was after subselective injection contrast under basal conditions during hyperemia. Time-intensity curves obtained from angiograms for both a myocardial region interest. Measurements included area curve, time peak contrast, disappearance rate. An index computed as ratio hyperemic measurements each these methods. Coronary ranged 6.5 142 ml/min, EMF ratios 0.80 4.2:1. The derived decay rate showed poor correlation (r = .34). between r .68 (y 0.16 x + 0.97). time-intensity curve interest close 0.91 0.1, .86). Thus estimates computer analysis can yield information regarding consequences