[Coronary perfusion: a classification based on the type and relative extension of coronary irrigation (II). An angiographic algorithm].

INTRODUCTION AND OBJECTIVES

An angiographic algorithm of clinical utility, applicable to conventional coronariography, is proposed to establish different patterns of coronary distribution depending on the characteristics of the myocardial perfusion, considering the starting point as the segmentary classification of the arterial irrigation of the left ventricle.

METHODS

To validate this system of classification, 30 hearts coming from necropsy were studied, through anatomical and angiographical analysis. The average age of the population studied was of 69.8 +/- 14.6 years. The range was between 26 and 91 years. To study them, the hearts were unrolled and after a coronariography and a dissection of the coronary arterial tree, the identification of the perfusion mode--exclusive or shared--of every left ventricle segment was done. Then an algorithm based on the type of division of the left main branch, and on the type of perfusion of the left ventricle inferobasal segment was applied to the angiographic frames. There was statistical analysis of the data obtained in the anatomic and angiographic studies. To verify the applicability of the algorithm, it was employed to successive series of 100 coronariographies in vivo, and these were then compared to the results obtained with the necropsy series.

RESULTS

The statistical comparison between the percentages of the classification obtained from both analyses of the necropsy series showed no significant differences. The statistical comparison of the percentages of the classification obtained between the in vivo and post-mortem analyses did not show any significant difference either.

CONCLUSIONS

The angiographical algorithm developed allows to classify the myocardial perfusion of the left ventricle, by the conventional coronary arteriography, in three groups of clinical interest. The classification is based on the predominance of the left ventricular segments exclusively irrigated by: the anterior interventricular artery (type I), the circumflex artery (type II), or a balance between both arteries (type III). The angiographic projections in left anterior oblique with caudal angulation and right anterior oblique are important for its application. The classification of the ventricular perfusion established with the developed algorithm can be validated as being equivalent to the one obtained through the anatomical series.