Factors determining early mortality in ischemic mitral regurgitation surgery

Abstract

Background: This study aims to identify the causes of early mortality in patients undergoing mitral valve surgery performed in combination with coronary artery bypass grafting for the treatment of ischemic mitral regurgitation.

Methods: Between January 2017 and January 2023, a total of 411 patients (272 males, 139 females; mean age: 63.1±9.1 years; range, 32 to 92 years) who underwent coronary artery bypass grafting and mitral valve surgery due to ischemic mitral regurgitation were retrospectively analyzed. The primary outcome measure of the study was in-hospital mortality. The patients were divided into two groups as those with and without in-hospital mortality. Variables affecting mortality were identified.

Results: In-hospital mortality was observed in 13.6% (n=56) of the patients. Elective surgery was performed in 308 patients (74.9%), while priority surgery was performed in 103 patients (25.1%). Mortality rate was 9.1% in elective cases and 27.1% in priority cases. Independent risk factors for mortality included age (p=0.001), female sex (p<0.001), priority surgery (p=0.005), low left ventricular ejection fraction (p=0.005), high creatinine levels (p=0.002), the presence of extracardiac arteriopathy (p=0.042), and prolonged cardiopulmonary bypass time (p<0.001). In priority cases, a waiting period of ≤9 days was associated with higher mortality (area under the curve: 0.781, sensitivity: 75%, specificity: 72%, p<0.001).

Conclusion: A comprehensive preoperative evaluation is crucial for optimizing outcomes in patients with ischemic mitral regurgitation. In high-risk cases, the use of less invasive approaches, such as percutaneous interventions, can be considered potential alternatives. In priority cases, if hemodynamic stability can be achieved, waiting nine days after the index event before performing surgical intervention may significantly reduce perioperative and in-hospital mortality rates.

Keywords: Coronary artery bypass grafting; mitral valve regurgitation; postoperative mortality; risk factors..

Figure 1. Evaluation of waiting time in priority cases using ROC curve. ROC: Receiver operating characteristic.

Figure 2. Evaluation of the use of variables in mortality prediction with ROC curve. HCT: Hematocrit; LVEF: Left ventricular ejection fraction, CCT: Cross clamp time; PAP: Pulmonary artery pressure; CRE: Creatine; ROC: Receiver operating characteristic.