Outcome Analysis and Risk Factors for Perioperative Myocardial Ischemia After Elective Aortic Surgery

Abstract

Perioperative myocardial ischemia (PMI) after non-cardiac surgery remains a serious postoperative complication. This study analyzed the risk factors and outcomes of patients who suffered from PMI after elective aortic surgery. Data from 863 patients who underwent elective aortic surgery for aneurysms or Leriche syndrome were retrospectively analysed with regard to PMI. The diagnosis of PMI was based on a positive serum troponin diagnostic test. According to the clinical signs and symptoms, the patients with PMI were divided into two groups: symptomatic and asymptomatic patients. Comorbidities, preoperative medication, intraoperative parameters, postoperative complications, mortality, length of intensive care stay and hospitalisation, as well as the long-term follow-up, were compared in a matched-pair analysis (1:3) with patients without PMI. Logistic regression analyses were performed to identify independent risk factors for PMI. Thirty-two patients with PMI were identified. Cardiac comorbidities (previous myocardial ischemia, P=0.0099; left ventricular systolic dysfunction, P=0.0429), ASA score ≥III (P=0.0114) and preoperative elevated creatinine (P=0.0194) were more common in patients who suffered PMI. The regression analysis confirmed that peripheral artery disease and prolonged operative duration >180 min are significant predictors of PMI. Surgical complications (wound healing deficit, P=0.0027; rate of secondary interventions during primary admission, P=0.0057) and medical complications (pneumonia, P=0.0002; renal dysfunction, P=0.0041) were more common in patients with PMI compared to the control group. Patients who suffered PMI remained in intensive care for a significantly longer period (P=0.0001) and were also hospitalized for longer (P=0.0001) than the control group. The long-term survival of patients who suffered PMI after aortic surgery was significantly worse than the control group (P < 0.0001, median 53 vs. 84 months), independent of clinical ischemia-associated symptoms. PMI after aortic surgery not only affects long-term survival, but also correlates with worsening of surgical outcome. Thus, meticulous preoperative risk stratification is required for high-risk patients, together with routine postoperative monitoring of troponin levels after aortic surgery.