Coronary Artery Bypass Surgery with or without Cardioplegic Arrest in Patients with Acute Myocardial Infarction

Objectives: Coronary artery bypass grafting (CABG) surgery for the treatment of acute myocardial infarction (AMI) is associated with increased risk compared with elective CABG. CABG can be performed with or without cardiopulmonary bypass and with or without cardioplegic arrest (CA). In the setting of AMI, it is unclear whether the use of CA provides additional myocardial protection to the infarcted myocardium or additional cardiac injury compared with approaches without CA. To date, the effects of the use of CA in the setting of AMI on perioperative and long-term outcomes are not sufficiently characterized.

Methods: Patients who underwent isolated CABG ≤5 days after AMI between 2008 and 2013 in two centers (n = 1,155) were included in the analysis. We compared outcomes up to 1 year postoperatively between patients who underwent CABG with CA or without CA (on-pump CABG with beating heart or off-pump CABG). Propensity score matching was applied to correct for relevant differences of baseline characteristics between the groups. After propensity score matching, 896 patients (CA group: n = 448; no CA group: n = 448) were included in the final analysis.

Results: Baseline characteristics were well balanced between the matched groups. EuroSCORE II in the CA group (10%) and no CA group (10%) was comparable (p = 0.81); 68% of patients in the no CA group underwent off-pump CABG and 32% received on-pump CABG with beating heart. Operation times were shorter in the no CA group (200 minutes; CA group: 217 minutes; p < 0.001). On the contrary, the mean number of coronary anastomoses was higher in the CA group (3.4) than in the no CA group (3.0; p < 0.001). Perioperative troponin- and CK-MB courses were equal in both groups. Thirty-day mortality (no CA group: 6.9%; CA group: 7.8%; p = 0.52) and perioperative stroke rates (no CA group: 2.4%; CA group: 1.8%; p = 0.64) were comparable. However, patients in the no CA group needed extracorporeal life support more frequently than patients in the CA group (2.7 vs. 1.4%; p = 0.039). One-year follow-up revealed similar survival rates (CA group 86% vs. no CA group 85%; p = 0.62) and similar stroke rates (CA group 5.6% vs. no CA group 5.1%; p = 1.00).

Conclusion: In patients undergoing CABG for AMI, the use of CA does not deteriorate clinical results or aggravate myocardial injury. These results suggest that CABG with and without CA is similarly safe and effective.