Effect of cold stimulation on coronary haemodynamics during exercise in patients with coronary artery disease

To assess if cold-induced vasoconstriction may persist during exercise and contribute to the development of myocardial ischaemia, we studied 11 patients with exertional angina and angiographically proven coronary artery disease, in all cases involving the proximal portion of the left anterior descending artery. Great cardiac vein flow (GCVF) was measured by the thermodilution technique and the coronary resistance of the abnormally perfused anterior region (ARCR) was calculated as the quotient of mean arterial pressure and GCVF. All patients performed a supine bicycle exercise test (ET1) until angina occurred. After recovery, they underwent a cold pressor test (CPT) and then performed a second exercise test (ET2) while cold stimulation was continued. During ET1, ARCR decreased (from 1.53±0.43 to 1.04±0.35 mmHg ml^-1 min^-1, P