Prognostic Impact of Right Ventricular Diastolic Dysfunction in Patients Undergoing Isolated Coronary Artery Bypass Grafting

Background: Right ventricular diastolic dysfunction (RVDD) increases the volume load on the right ventricle. We aimed to evaluate the association of RVDD with perioperative outcomes in patients undergoing isolated coronary artery bypass graft surgery (CABG). Methods: This single-center observational study included all consecutive isolated CABG patients with a left ventricular ejection fraction (LVEF)>40% from May 2022 to May 2023 who were evaluated for RV diastolic function by transthoracic echocardiography. We divided patients into two groups, with and without RVDD, and then compared the two groups in terms of the primary outcomes of the duration of hospitalization, intensive care unit (ICU) stay, and intubation time, and the secondary outcome composed of postoperative in-hospital complications. Results: Our study found that 49.1% of patients suffered from RVDD, and patients with RVDD had significantly lower systolic blood pressure and were more likely to take angiotensin-converting enzyme inhibitors than those without RVDD. There was no association between RVDD and primary outcomes of hospitalization time (beta=-0.01; 95% CI -0.05, 0.04; P value=0.717), ICU stay (beta=0.01; 95% CI -0.18, 0.17; P value=0.984) and intubation time ([beta=0.06; 95% CI -0.05, 0.17; P value=0.309). However, more postoperative complications occurred in patients with RVDD (90% vs. 85%). After adjustment for confounding factors, RVDD was not independently associated with primary and secondary outcomes. Conclusion: Preexisting RVDD in CABG patients with LVEF>40% increased postoperative complications but not significantly. More extensive studies are needed to evaluate RV diastolic function before cardiac surgery to identify high-risk patients and optimize their perioperative management.