Thromboxane and prostacyclin in patients with stenocardia in induced and spontaneous ischemia of the myocardium

: The levels of TxB2 and 6-keto-PGI alpha in the coronary sinus and thoracic aorta blood were determined in 14 patients with angina pectoris and signs of coronary atherosclerosis. 12 patients were involved in a dynamic study: before, during and 10 minutes after ischaemia-inducing atrial pacing. In all the patients atrial pacing resulted in a typical episode of angina, in 7 of them ST-segment depression of not less than 2 mm was seen on the ECG. In one patient arachidonic acid metabolites were evaluated during the control period and during a spontaneous episode of angina accompanied by ST-segment elevations. In 8 of 9 patients TxB2 was produced by the myocardium during atrial pacing. During monitored evaluation of arachidonic acid metabolites one patient with spontaneous angina demonstrated a gradual lowering of the 6-keto-PGI alpha, it being minimal by the beginning of the episode; TxB2 level increased more rapidly.