Off-Pump Coronary Artery Bypass Grafting is Associated With Reduced Operative Mortality and In-Hospital Adverse Events in Patients With Left Main Coronary Artery Disease

Role of Left Main Coronary Artery Stenosis on Intraoperative Conversion and Mortality in Off-Pump Coronary Artery Bypass

BACKGROUND

Intraoperative conversion is a major threat in off-pump coronary artery bypass (OPCAB). The conversion rate depends on patient selection and surgeon experience. Previous studies have demonstrated the feasibility of OPCAB for patients with left main coronary artery stenosis (LMCAS) ≥ 50%. However, no studies have focused on the role of LMCAS ≥ 90%. We sought to assess the impact of LMCAS ≥ 90% on the conversion rate and mortality in OPCAB.

METHODS

We conducted a retrospective review of 1055 consecutive unselected patients undergoing OPCAB between 2000 and 2012. The patients in our study were divided into 3 groups by the severity of LMCAS.

RESULTS

LMCAS was < 50% in 704, 50-90% in 266, and ≥ 90% in 85 patients. LMCAS was not associated with major postoperative complications and hospital mortality, although preoperative cardiogenic shock was present in 6.3%. Overall, the conversion rate was 10.1%:11.4% in LMCAS < 50%, 5.6% in LMCAS 50-90%, and 14.1% in LMCAS ≥ 90%. Operation status, cardiogenic shock, left ventricular ejection fraction < 30% and operation before 2007 were noted as independent predictors of conversion. The overall hospital mortality rate was 5.1%: 4.8% in LMCAS < 50%, 4.5% in LMCAS 50-90%, and 9.4% in LMCAS ≥ 90%. Operation status, cardiogenic shock, left ventricular ejection fraction < 30% and intraoperative conversion were observed to be independent predictors of mortality. However, LMCAS did not predict either conversion or hospital mortality.

CONCLUSIONS

LMCAS ≥ 90% was not an independent predictor of intraoperative conversion or hospital mortality in OPCAB.

KEY WORDS

Conversion; Left main coronary artery stenosis; Off-pump coronary artery bypass.