Development of a risk score for predicting 30-day mortality in Brazilian heart valve surgery patients

Abstract Introduction There has been an increasing global prevalence of heart valve disease, which is associated with significant morbidity and mortality, often requiring valvular intervention to improve survival. However, existing surgical risk scores were developed based on populations with distinct clinical and epidemiological profiles compared to Brazil, where rheumatic heart disease remains highly prevalent. Objectives To conduct a comprehensive analysis of patients who underwent heart valve surgery and identify new specific predictors of mortality. Methods unicentric retroespective study including 796 patients who underwent heart valve surgery in Brazil. Clinical and epidemiological data, as well as 30-day surgical outcomes, were analyzed. Results The mean age was 58 ± 15 years, with 458 patients (57.7%) being male. The most common comorbidities were hypertension (60.5%), atrial fibrillation (29.6%), diabetes (18.5%), and previous stroke (8.9%). A total of 235 patients (29.6%) had undergone prior cardiac surgery. Most patients (83.2%) presented with dyspnea as the main symptom, with 66.2% classified as NYHA functional class III or IV. The mean left ventricular ejection fraction (LVEF) was 56.9 ± 11.8%, and the mean pulmonary systolic arterial pressure was 48.3 ± 19.1 mmHg. The most prevalent severe valve diseases were mitral regurgitation (29.9%), mitral stenosis (13.9%), aortic regurgitation (11.6%), aortic stenosis (24.6%), and tricuspid regurgitation (10.6%). Regarding outcomes, the overall 30-day mortality rate was 14.2%. Stroke occurred in 1.9% of patients, while 14.1% experienced bleeding requiring transfusion, 7.4% developed surgical site infections, 4.4% had infective endocarditis, and 7.3% required reoperation. Additionally, atrial fibrillation or atrial flutter occurred in 17.0% of patients, and a permanent pacemaker was implanted in 3.0% of cases. In the binary logistic regression analysis, age, atrial fibrillation, LVEF, hemoglobin, creatinine clearance, and cardiopulmonary bypass time were identified as predictors of 30-day mortality (Figure 1). A new risk score was developed using the following formula: 1.118 + (age × 0.027) + (LVEF × -0.033) + (hemoglobin × -0.257) + (creatinine clearance × -0.021) + (bypass time × 0.011) + (diabetes × 0.513) + (atrial fibrillation × 0.805). The newly developed risk score was a predictor of 30-day mortality (OR 2.725, 95% CI 2.210–3.361, p0.001) and demonstrated good discriminative ability (AUC 0.813, Figure 2). Conclusion In a contemporary cohort of Brazilian patients who underwent heart valve surgery, a newly developed risk score based on age, LVEF, hemoglobin level, creatinine clearance, cardiopulmonary bypass time, and history of atrial fibrillation was found to be a strong predictor of 30-day overall mortality.Figure 1 Figure 2