Coronary artery vasoregulation and left ventricular function in patients with angina pectoris‐like pain and normal coronary angiograms

Twenty patients with angina pectoris-like pain, normal coronary angiography and abnormal exercise 201Tl scans were investigated by means of haemodynamic, coronary sinus blood flow and lactate determinations before and after cold provocation, pacing and dipyridamole infusion. Radionuclide angiography, a new exercise 201Tl scan and noninvasive hyperventilation and ergonovine tests were performed. Intracoronary infusions of acetylcholine were given in increasing doses and a second coronary angiogram in combination with a 201Tl scintigram was performed. Despite a previously pathological 201Tl scintigram, with reversible perfusion defects, only ten of the patients had reversible perfusion defects at the second investigation. Hyperventilation and ergonovine tests did not result in ECG signs indicative of coronary spasm. Intracoronary infusion of acetylcholine resulted in a diffuse coronary constriction in 3 of 14 patients, and in one patient a perfusion defect was observed on thallium scintigram. In conclusion, although most of the common methods for inducing coronary vasospasm were used, no consistent pattern of reaction was found to explain the chest pains experienced in this group of patients.