Abstract 18236: Enhancing Predictive Accuracy of H2FPEF Score in Suspected HFpEF by Incorporating Left Atrial Reservoir Strain

Abstract

Introduction: Diagnosing HFpEF can be challenging, but the H 2 FPEF score is a valuable tool for clinical decision-making. Atrial fibrillation (AF) plays a significant role in this score, creating challenges for diagnosis in patients without AF or with paroxysmal AF. Left atrial reservoir strain (LArS) has emerged as a promising indicator for both AF and HFpEF. This study explores how incorporating LArS can enhance the predictive ability of the H 2 FPEF score for exercise capacity in outpatients with suspected HFpEF. Methods: This cross-sectional study has a sample size of 283 patients with suspected HFpEF. We collected clinical and echocardiographic data and compared LArS values across different H 2 FPEF score categories. Additionally, we analyzed a subgroup of 129 patients who underwent a Cardiopulmonary Exercise Test (CPET) to evaluate the effectiveness of the H 2 FPEF score and LArS in predicting Peak VO 2 . To further comprehend the contribution of each feature in the performance of the H 2 FPEF score, we used Shapley Additive Explanations (SHAP) analysis. Results: Most patients were female (63%), age of 60 (±12) years and LVEF of 60 (±5.2)%. Patients with low scores had a LArS of 32.6 (± 6.8)%, while those with moderate and high scores had probabilities of 26(± 8.2)% and 16 (±8.2)%, respectively (p<0.001). The H 2 FPEF score demonstrated an AUC of 0.74 (95% CI: 0.64-0.84) in predicting peak VO 2 , whereas LArS exhibited an AUC of 0.71 (95% CI: 0.62-0.80). Incorporating LArS into the score improved its performance, resulting in an AUC of 0.82 (95% CI: 0.75-0.89). The SHAP analysis revealed that LArS had a significant impact as the most important feature (Figure 1), while the importance of the atrial fibrillation criterion decreased significantly. Conclusions: Our findings show that integrating LArS improves the diagnostic performance of the H 2 FPEF score and offers a valuable alternative to the AF criterion within the H 2 FPEF algorithm.