Minimally invasive cardiac surgery - coronary artery bypass grafting in patients with low left ventricular ejection fraction

Patients with coronary artery disease (CAD) with low left ventricular ejection fraction (LLVEF) (LVEF ≤ 35%) are not considered suitable for minimally invasive cardiac surgery - off-pump coronary artery bypass grafting (MICS OPCABG) due to poor cardiac function reserve. We retrospectively analyzed 38 consecutive CAD patients with LLVEF who underwent MICS OPCABG from January 2022 to December 2024. We collected perioperative and follow-up data to evaluate the feasibility of this procedure as well as mid-term prognosis. The mean age of the study patients was 65.5 ± 8.8 years, and the preoperative LVEF was 29.2 ± 4.0%. 15 patients (39.5%) had diabetes mellitus, 6 patients (15.8%) had chronic kidney disease (CKD). Mitral regurgitation (MR) was combined in 36 cases (94.7%). The in-hospital mortality rate was 7.89% (3/38). LVEF gradually improved: it increased to 42.3 ± 6.8% at postoperative 3 months (P < 0.001vs baseline), 48.1 ± 7.2% at postoperative 12 months (P < 0.001vs baseline), and stabilized at 49.5 ± 6.5% at postoperative 24 months. Mitral regurgitant area (MRA) was significantly reduced: it decreased to 5.1 ± 2.3 cm² at postoperative 3 months (P < 0.001vs baseline), and stabilized at 4.9 ± 2.3 cm² at postoperative 12 months (P < 0.001vs baseline), and 4.8 ± 2.1 cm² at postoperative 24 months. The 3-year all-cause cumulative mortality rate was 15.29%. Multivariable Cox regression showed that preoperative LVEF ≤ 25% (HR = 3.29, 95%CI 1.98–9.83, P = 0.022), combined preoperative CKD (HR = 2.77, 95%CI 1.08–6.65, P = 0.026) and LIMA-LAD blood flow ≤ 15 ml/min (HR = 1.97, 95%CI 1.31–3.93, P = 0.041) were independent predictors of 3-year mortality. In addition, the 3-year all-cause cumulative graft patency rate was 87.23%. MICS OPCABG provides a combined improvement in LVEF and MR and a favorable graft patency rate for CAD patients with LLVEF and ischemic MR.