Morbidity, cost, and six-month outcome of minimally invasive direct coronary artery bypass grafting

Background. Minimally invasive direct coronary artery bypass grafting (MIDCABG) promises to reduce the morbidity of coronary bypass, but this has not been proved. Methods. This retrospective study compares the morbidity, mortality, cost, and 6-month outcome of patients less than 80 years old undergoing elective left internal mammary artery to left anterior descending artery bypass grafting via MIDCABG (n = 60) or sternotomy (n = 55) between January 1995 and December 1996. There were no differences between the groups in mean age, sex distribution, or preoperative risk level. The left internal mammary artery was mobilized from the fifth costal cartilage to the subclavian artery in all patients. The anastomoses were done with a beating heart in the MIDCABG group and with cardioplegic arrest in the sternotomy group. Results. There were no operative deaths in either group. The MIDCABG patients had a lower transfusion incidence (10/60 [17%] versus 22/55 [40%]; p ≤ 0.02) and a shorter postoperative intubation time (2.1 ± 4.2 versus 12.6 ± 9 hours; p ≤ 0.0001). One patient in each group was reexplored for bleeding. Three sternotomy patients (3/55, 5%) required ventilatory support for greater than 48 hours, but no MIDCABG patient was ventilated for more than 24 hours. Median postoperative length of stay was 4 days for MIDCABG and 7 days for sternotomy. Estimated hospital costs were $11,200 ± 3100 for MIDCABG and $15,600 ± 4200 for CABG (p< 0.001). The reduced morbidity and cost of MIDCABG was found mostly in high-risk patients. At 6-month follow-up, 5 MIDCABG patients (5/60, 8%) had evidence of recurrent ischemia involving the left anterior descending artery, primarily the result of anastomotic stricture. Conclusions. This analysis shows that MIDCABG reduces the initial morbidity and cost of coronary bypass, but some patients require subsequent reintervention. Long-term follow-up is needed before MIDCABG can be judged better than traditional bypass, but the initial results are promising, especially in high-risk patients.