Coronary surgery for acute coronary syndrome: which determinants of outcome remain?

Abstract

Background: The mortality risk associated with coronary artery bypass grafting (CABG) after acute myocardial infarction remains controversial. The objective of the present study was therefore to analyze the outcome and predictors of in-hospital mortality in patients (pts) referred to CABG with acute coronary syndrome (ACS).

Patients and methods: Between January 2003 and May 2005, a total of 3,127 pts underwent primary isolated CABG at our institution, including 220 pts with ACS. Out of these, unstable angina pectoris was present in 88 pts (group I), 97 pts (group II) had non-ST-elevation infarction, whereas 35 pts (group III) had ST-elevation infarction. Clinical data, in-hospital morbidity and mortality were recorded and studied retrospectively.

Results: Overall in-hospital mortality was 6.4% (n = 14) in the complete cohort, being 2.2% in group I (n = 2), 9.2% in group II (n = 9) and 8.5% (n = 3) in group III (P < 0.05). Logistic regression and receiver operating characteristic analyses identified age, NYHA, ejection fraction < 45%, catecholamine support, cardiogenic shock, renal disease and the additive EuroSCORE > 10 (P < 0.0001) as significant predictors related to in-hospital mortality. The mean time from the onset of symptoms to revascularization differed significantly between survivors (5.1 +/- 2.7 h) and no survivors (11.4 +/- 3.2 h) (P < 0.0007) in the STEMI group. Preoperative cTnI did not provide any prognostic information.

Conclusion: CABG in pts with ACS can be performed with good clinical results. The clinical outcome is particular depending on the different groups of ACS. Therefore an individual risk stratification of each pts in ACS is necessary. The time interval of 6 h seems to be crucial as prognostic variable in the STEMI-group.