Prevention of coronary spasm during and shortly after coronary revascularization in patients with variant angina

: From June 1990 to March 1993, 9 patients undergoing coronary artery bypass grafting (CABG), 4.4% of all CABG cases at our hospital during this period, had significant perioperative coronary spasm. For 4 patients who underwent CABG before May 1992 (Group 1), preventive and suppressive procedures for the coronary spasm were the addition of diltiazem in the cardioplegic solution and the continuous intravenous infusion of nitroglycerin. Perioperative myocardial infarction (PMI) occurred in all 4 patients in Group 1, with the mean peak MB-CPK of 356 +/- 197 IU/l. One patient had delayed sternal closure because of his unstable hemodynamic status. Thereafter, we changed our protocol as follows: 1) Ergometrine loading (intracoronary infusion) test was performed in all candidates for CABG, aiming at finding out patients with a high risk. And for the high-risk patients, in addition to the measures done in Group 1, 2) intraaortic balloon pumping was performed through the perioperative period, and 3) a pig-tail catheter was dwelled in the Valsalva sinus, through which bolus doses of isosorbide dinitrate were injected frequently in this period. 4) Additionally nifedipine was periodically administered through the nasogastric tube. With these intensive preventive/suppressive measures, the perioperative spasm in 5 patients (Group 2) with variant angina were successfully managed, with no resultant PMI nor operative death (The occurrence of PMI was significantly less frequent in Group 2 than in Group 1, with the p value < 0.05). For patients with variant angina undergoing CABG, combined intensive preventive/suppressive measures for perioperative coronary spasm as listed above proved effective.