Angiographic demonstration of spontaneous diffuse three vessel coronary artery spasm

AbstractThe spontaneous occurrence of diffuse three vessel coronary artery spasm was documented during routine coronary angiography in three patients with a history of variant angina. Quantitative angiographic analysis of 18 arterial segments demonstrated that the mean luminal diameter of 1.47 mm during spasm increased to 2.47 mm after the administration of nitroglycerin (p < 0.0001). The underlying coronary arteries were normal or near normal.Although multivessel spasm has previously been considered to be uncommon and its spontaneous occurrence during angiography only rarely documented, these cases suggest that it may be more common than previously recognized. In addition to important diagnostic considerations, this phenomenon may have important implications regarding the pathophysiologic role of endothelium in coronary artery spasm

Assessment of myocardial perfusion by videodensitometry in the canine model

Assessment of the functional severity of coronary stenoses has become increasingly important as the intrinsic limitations of coronary angiography have been documented. Videodensitometric coronary flow reserve has been proposed as a means to assess the physiologic significance of a coronary stenosis in humans. This study compared videodensitometric assessment of coronary flow with microsphere quantitation in the closed chest canine model.In five dogs, flow rates were assessed at baseline, after vasodilation with adenosine, after vasoconstriction with vasopressin and during rapid cardiac pacing. The videodensitometric peak density, time to one-half peak density and washout time (time from peak to one-half peak density) were compared at each flow state with flow assessed by microsphere injection. Reproducibility of videodensitometric measurements from two different coronary injections during the same flow state was best with peak density (r = 0.94).Videodensitometric flow ratios (flow state under study to flow at rest) using peak density demonstrated a fair correlation with flow ratios by microsphere (r = 0.81). There was poor correlation between flow ratios when time to one-half peak or washout time was used.Videodensitometric flow measurements used in vivo to assess a wide range of drug-induced coronary flows may not accurately reflect coronary flow measured by microsphere

SMOKING IS A STRONG INDEPENDENT PREDICTOR FOR FUNCTIONAL SIGNIFICANCE OF INTERMEDIATE CORONARY LESIONS

Refiere un ejercicio para mejorar el estilo del periodista. Evoca la necesidad de escribir al menos con claridad corrección y naturalida