[Coronary venous oxygen saturation dynamics during intracoronary infusion of ergonovine or acetylcholine in vasospastic angina].

We investigated changes in coronary venous oxygen saturation (CSO2-Sat) dynamics during intracoronary infusion of ergonovine (ERG) or acetylcholine (ACh) in patients with vasospastic angina. In 16 patients with suspected vasospasm in the left coronary artery, intracoronary ERG injection provoked vasospasm in 4 out of 6 patients, and intracoronary ACh in 6 out of 11 patients. A gradual decrease in CSO2-Sat, anteceding angina and ischemic ECG evidence, was characteristic in ERG-induced vasospastic patients, while no significant change of CSO2-Sat was observed in non ERG-induced patients. Intracoronary infusion of ACh was followed in all 11 patients by a transient increase in CSO2-Sat, suggesting decreased myocardial oxygen extraction due to increased coronary blood flow with ACh. However, earlier and sudden decreases in CSO2-Sat below the control levels were characteristic in 6 patients with ACh-induced vasospastic angina. These findings suggest that effects of ERG and ACh on coronary flow dynamics are essentially different although both drugs can provoke vasospasm.