[Relation between coronary obstructions, left ventricular wall motion and regional myocardial blood flow in single-vessel coronary artery disease (author's transl)].

UNLABELLED

Regional myocardial blood flow was studied at rest in 72 patients with a typical history of angina pectoris and/or myocardial infarction using the 133Xenon clearance technique. 62 patients had isolated greater than 50% obstructions of the left anterior descending or of the left circumflex branch, 10 patients had segmental asynergy yet no or only minimal (less than 35%) coronary obstructions. In each patient, flow of the poststenotic (asynergic) LV wall area was related to flow of the normal area (= 100%). Coronary obstructions were measured in multiple projections using a vernier, and segmental wall motion was quantitated by systolic halfaxial shortening.

RESULTS

A progressive decrease of poststenotic flow was found with increasing severity of coronary obstructions: in relation to the respective normal areas, poststenotic flow was reduced to 84% distal to 50-75% obstructions (p less than 0.01), to 75% distal to 76-90% obstructions (p less than 0.0005), and to 67% distal to less than 90% obstructions (p less than 0.0005). However, analysis of poststenotic LV wall motion suggested that flow was correlated more closely to poststenotic wall motion: in hypokinetic areas, flow was reduced to 75% (p less than 0.0005), and in akinetic areas to 55% (p less than 0.0005) whereas in poststenotic areas with normal wall motion resting flow was normal regardless of the severity of coronary obstructions. Furthermore, the reduction of flow in asynergic areas of patients without coronary obstructions was comparable to flow in asynergic areas supplied by severely stenosed vessels. Thus in chronic coronary heart disease, regional myocardial blood flow correlates not only to the severity of coronary obstructions but also to segmental left ventricular wall motion.