Early angiographic control of perioperative ischemia after coronary artery bypass grafting

Objective: To assess the impact of immediate angiography in patients with defined clinical and laboratory criteria of perioperative myocardial infarction after coronary artery bypass operation. Patients and methods: Between January 1999 and December 1999 2052 patients underwent coronary artery bypass grafting in our institution. Out of this cohort 131 (6.4%) patients met the criteria of perioperative myocardial ischemia, which was defined as: (a) increase in the isoenzyme ratio of creatinine phosphokinase (CK/CK-MB) above 10%; (b) ischemic electrocardiographic episodes (defined as a new onset of elevated ST-segment change lasting at least 1 min and involving a shift from baseline of greater than or equal to 0.1 mV of ST-depression and a new association of a postoperative Q; (c) recurrent episodes of, or sustained ventricular tachyarrhythmia as well as ventricular fibrillation; (d) hemodynamic deterioration despite adequate inotropic support. Results: Angiography was performed in 108 patients: (5.3%, group A) whereas 23 patients (1.1%, group B) were immediately re-operated due to severely compromised hemodynamics. Angiographic results in group A showed regular grafts in 45 patients (2.2%); 63 patients (3.1%) had either an occlusion (n = 41), incorrect anastomosis (n = 29), graft stenosis (n = 14), graft spasm (n = 6), displaced graft (n = 6), poor distal run-off (n = 5) or incomplete revascularization (n = 2). In group A 43 patients underwent a re-operation (34 patients) or an early angioplasty (nine patients). Due to poor coronary artery status no intervention was performed in the remaining 20 patients with angiographic findings. Operative findings in group B showed graft occlusion in ten patients (43.5%), incorrect anastomosis in five patients (21.7%), bleeding, stretched graft, venous graft spasm and displaced graft in one patient (4.3%) each, and no patho-morphological finding in 4 patients (17.4%). Thirty-day mortality rate was ten patients in group A (9.3%), all of them with angiographic findings, as opposed to nine patients (39.1%) in group B. Conclusion: ST-change and elevated CK/CK-MB enzyme ratio is highly indicative for possible graft failure and should be followed early angiographic control to assess the need for reintervention. (C) 2001 Elsevier Science B.V. All rights reserved.