Early and Late Outcomes after Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) versus Full Sternotomy Off-Pump Coronary Artery Bypass Grafting: A Propensity Score Adjusted Analysis

Background: Minimally-invasive direct coronary artery bypass (MIDCAB) has been introduced as a less-invasive alternative to full sternotomy off pump coronary artery bypass (FS-OPCAB) revascularization of the left anterior descending artery (LAD). Data comparing MIDCAB to FS-OPCAB especially in regard to long-term follow-up is scarce. We compared short- and long-term results of MIDCAB versus FS-OPCAB revascularization over a maximum follow-up period of 10 years.

Methods: From December 2009 to June 2020, a total of 388 elective patients were included in our retrospective study. 229 underwent MIDCAB, and 159 underwent off-pump LIMA-to-LAD myocardial revascularization via median sternotomy. Inverse propensity score weighting (IPTW) was used to adjust for selection bias and to estimate treatment effects on short- and long-term outcomes. IPTW-adjusted Kaplan–Meier estimates by study group were calculated for all-cause mortality, stroke and the risk of repeat revascularization up to a maximum follow-up of 10 years.

Results: MIDCAB patients had less rethoracotomies (n = 13/3.6% vs. n = 30/8.0%, p = 0.012), fewer transfusions (0.93 units ± 1.83 vs. 1.61 units ± 2.52, p < 0.001), shorter mechanical ventilation time (7.6 ± 4.7 vs. 12.1 ± 26.4 hours, p = 0.005), and needed less hemofiltration (n = 0/0% vs. n = 8/2.4%, p = 0.004) when compared to FS-OPCAB group. 30-day mortality did not differ significantly between the two groups (n = 0/0% vs. n = 3/0.8%, p = 0.25). Long-term outcomes did not differ significantly between study groups. In the FS-OPCAB group, probability of survival at 1, 5, and 10 years was 98.4%, 87.8%, and 71.7%, respectively. In the MIDCAB group, the corresponding values were 98.4%, 87.7%, and 68.7%, respectively (RR 1.24, CI 0.87–1.86, p = 0.7). In the FS group, freedom from stroke at 1, 5, and 10 years was 97.0%, 93.0%, and 93.0%, respectively. In the MIDCAB group, the corresponding values were 98.5%, 96.9%, and 94.3%, respectively (RR 0.52, CI 0.25–1.09, p = 0.06). Freedom from repeat revascularization at 1, 5, and 10 years in the FS-OPCAB group was 92.2%, 84.7%, and 79.5%, respectively. In the MIDCAB group, the corresponding values were 94.8%, 90.2%, and 81.7%, respectively (RR 0.73, CI 0.47–1.16, p = 0.22).

Conclusion: MIDCAB is a safe and efficacious technique for patients requiring isolated LAD grafting and offers comparable long-term results in terms of mortality, stroke and repeat revascularization when compared to FS-OPCAB.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
13 February 2024