Left atrial–left ventricular coupling index as a novel diagnostic and prognostic marker in HFpEF: systematic review and meta-analysis

Introduction Diagnosing heart failure with preserved ejection fraction (HFpEF) remains challenging due to a broad spectrum of differential diagnoses. The left atrial coupling index (LACI) integrates the volume of the left atrium and the left ventricle at end-diastole and could be an echocardiographic marker to aid in a more accurate diagnosis of HFpEF. Purpose We conducted a systematic review and meta-analysis searching for studies that assessed the correlation between LACI values estimated by echocardiography ​​and the diagnosis and prognosis of HFpEF. Methods We searched Pubmed, Embase and Cochrane databases for studies that assessed the correlation between LACI values estimated by echocardiography ​​and the diagnosis and prognosis of HFpEF. Diagnostic accuracy outcomes, sensitivity, specificity, positive predicted value (PPV), and negative predicted value (NPV) were calculated and pooled using random-effects models to account for between-study heterogeneity. For prognostic outcomes, pairwise meta-analyses were conducted by pooling hazard ratios (HR) and their corresponding 95% confidence intervals (CI). Heterogeneity was assessed using the I² statistic. Results A total of seven observational studies, encompassing 5,689 patients (1,354 with HFpEF), met the inclusion criteria. LACI demonstrated high sensitivity for diagnosing HFpEF, with a pooled estimate of 0.89 (95% CI 0.57–0.95), as well pooled specificity of 0.84 (95% CI 0.67–0.93). NPV was consistently high, with a pooled estimate of 0.93 (95% CI 0.77–0.98; I²=98.6%) and PPV averaged 0.67 (95% CI 0.37–0.87; I²=98%). Elevated LACI was associated with a significantly higher risk of the composite outcome (HR 1.16; 95% CI 1.07–1.25; p=0.0003, I²=0%) (Figure 1). The Receiver Operating Characteristic curve analysis identified 28.4% as the optimal diagnostic threshold for the volumetric diastolic LACI (Figure 2). Conclusions LACI measure provides high diagnostic sensitivity with excellent rule-out capability and shows consistent association with adverse cardiovascular outcomes in HFpEF. While further validation is required, LACI holds promise as a practical imaging marker with potential to support earlier recognition, individualized risk stratification, and improved management of patients with HFpEF.