Left atrial–left ventricular coupling index as a novel diagnostic and prognostic marker in HFpEF: systematic review and meta-analysis
C Fischer Bacca, J Peres de Oliveira, R Huntermann, P G Batista, M E Molinari, M V Montenegro, L A Lucena, G C Gaelzer, M Malik, J GiorgiAbstract
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.Figure 1