Localization of a Coronary Stenosis, Left Ventricular Function, and Pain Perception During Myocardial Ischemia in Patients with One-Vessel Disease

Silent Myocardial Ischemia and Endogenous Pain Modulation. A total of 97 patients withasymptomatic and 69 patients with symptomatic myocardial ischemia and one-vessel diseasewere compared with respect to the location of coronary stenosis and left ventricular wall motionahnormalities. All symptomatic and asymptomatic patients exhibited reproducible objectivesigns of myocardial ischemia in exercise tests, ischemia being always silent in the asymptomaticgroup. Right coronary artery stenosis (and left circumflex artery stenosis) was more frequentlyobserved in asymptomatic patients, left artery descending stenosis more often in symptomaticpatients. Left ventricular wall movement abnormalities with posterobasal or diaphragmaticlocalization were significantly more often associated with the absence of angina pectoris pain.The present results could contribute to the understanding of the mechanisms underlying theabsence of pain in silent myocardial ischemia. A possible explanation for these results would bethat stimulation of inhibitory vagal afferents, which are preferentially distributed in the inferiorventricle wall, may play a role of the suppression of pain perception in myocardial ischemia, (JCardiovasc Electrophysiol, Vol. 2, Supplement, pp. S68-S75, April 1991)silent myocardial ischemia, endogenous pain modulation, vagal inhibitionIntroduction