ORIGINAL ARTICLES Provocation of Coronary Artery Spasm by the Cold Pressor Test Hemodynamic, Arteriographic and Quantitative Angiographic Observations

In this study we attempted to determine if the cold pressor test, a known sympathetic reflexogenic stimulus, could precipitate coronary artery spasm. Thirty-five patients undergoing coronary arteriography for evaluation of chest pain syndromes were given the cold pressor test. During 1 minute of cold pressor stimulation, aortic systolic pressure increased 18.1 ± 9.7 mm Hg (mean ± SD) and heart rate did not change significantly. Focal coronary artery spasm was provoked in seven patients, each of whom had an atheromatous plaque at the site of spasm. Four of six patients with a precatheterization clinical diagnosis of variant angina (group 1) had coronary artery spasm, and two of the four had associated ischemic manifestations. Of 14 patients in whom classic angina (group 2) was diagnosed before cardiac catheterization, two manifested focal coronary spasm. One of 15 patients thought to have atypical chest pain (group 3) manifested spasm. There were no significant differences in baseline variables (aortic systolic or diastolic pressure, heart rate, double product and left ventricular end-diastolic pressure) or hemodynamic response (aortic systolic pressure, heart rate or double product) to cold pressor stimulation between patients in each group and between those who manifested spasm and those who did not. Ventricular ectopy and ventricular tachycardia developed in one patient but were readily reversed with intravenous nitroglycerin. Quantitative angiography showed that the luminal diameter of normal coronary segments significantly decreased in each group of patients in response to cold pressor stimulation, but this response was most pronounced in the variant angina group (-12.7 ± 11.5% from control in group 1, -5.1 ± 10.2% in group 2, and -7.9 ± 9.6% in group 3; p < 0.001 for each group). Patients who are prone to coronary spasm may represent one extreme of a spectrum of reactivity to a coronary vasoconstrictive stimulus. The cold pressor test can provoke focal coronary artery spasm in certain patients and may be a useful nonpharmacologic provocative screening test to aid in the diagnosis of this phenomenon.