Incidence and hospital mortality of vascular surgery patients with perioperative myocardial infarction (PMI) or myocardial injury after non-cardiac surgery (MINS)

Abstract

Background: Perioperative myocardial infarction (PMI) and prognostically relevant myocardial injury following non-cardiac surgery (MINS) increases perioperative mortality. Studies in vascular patients show an increased incidence and mortality from PMI. However, there remains limited data on the relative prognostic importance of PMI and MINS in South African vascular surgical patients. The primary objective was to evaluate the incidence and prognosis of PMI and MINS in vascular surgical patients admitted to intensive care. The secondary objective was to identify predictors of PMI and hospital mortality.
Methods: A retrospective electronic patient record review of all patients aged at least 45 years admitted to Inkosi Albert Luthuli Central Hospital (IALCH) intensive care unit (ICU) following vascular surgery between 1 January 2011 and 31 December 2013 was carried out.
Results: A total of 140 vascular patients were reviewed; 24.3% of the patients had a PMI and a further 25% had MINS. PMI was associated with significantly increased hospital mortality of 58.8% (p < 0.01) and MINS was not (20%, p = 1.00). Increasing age, the highest postoperative B-type natriuretic peptide (BNP) and a blood transfusion within the first three days postoperatively were independent predictors of PMI. PMI and a history of congestive cardiac failure were independent predictors of hospital mortality.
Conclusion: PMI and MINS are present in nearly 50% of vascular patients admitted to intensive care postoperatively. PMI but not MINS in these patients was significantly associated with hospital mortality. MINS requires strict diagnostic criteria in the intensive care where other non-ischaemic pathologies may be associated with myocardial injury.