Is reoperative coronary artery bypass grafting in patients with poor left ventricular ejection fractions < or = 25% worthwhile?

AIM

This study aimed to investigate whether patients with very low left ventricular ejection fractions (LVEF) should be accepted for reoperative coronary artery bypass grafting (CABG).

STUDY POPULATION

Between January 1990 and December 1993, 1681 patients underwent primary CABG and 308 (15.5%) reoperative CABG. One hundred and eight patients (5.4%) had an LVEF < or = 25%, 91 patients for primary CAGB (group I) and 17 for CABG (group II). The mean age of the patients was 62 years. Sex distribution and preoperative risk factors did not differ. Urgent operations were more frequently necessary in group II (P < 0.01). Mitral regurgitation was present in 49% of the group I patients and 18% of the group II patients (P < 0.05). Pulmonary artery hypertension was observed in 24% of group I patients, but in only 6% in group II patients. The mean LVEF was 21% and left ventricular end-diastolic pressure 18 mmHg, without between-group differences. All patients had significant two- or three-vessel disease (stenosis > or = 70%). An average of 4.5 grafts per patient were performed. Mitral valve surgery was not performed in any of the patients.

RESULTS

The postoperative mortality was significantly higher in reoperative CABG patients (group II; 23.5%) than in group I patients (12.1%; P < 0.05), whereas the incidence of non-fatal myocardial infarction did not differ. The incidence of postoperative complications did not differ between the groups, except for transient renal failure, more frequently encountered in group II (P < 0.05). After an average follow-up of 18 months, the New York Heart Association (NYHA) class and the LVEF were significantly improved in both groups (NYHA class from 3.5 to 1.8 and LVEF from 21% to 45%; P < 0.001). The mitral regurgitation had improved or completely disappeared at the end of follow-up in all patients in both groups.

CONCLUSIONS

Our results suggest that patients with left ventricular ejection fraction < or = 25%, angina and significant two- or three-vessel coronary artery disease should not categorically be refused for reoperative CABG. Careful patient selection is necessary because of an increased operative risk.