https://doi.org/10.1007/s00392-025-02625-4
1Universitätsklinikum Heidelberg Klinik für Innere Med. III, Kardiologie, Angiologie u. Pneumologie Heidelberg, Deutschland
Introduction
Patients with chronic coronary syndrome (CCS) are at risk of adverse cardiovascular events, making risk stratification crucial. The complex interplay between the left atrium and left ventricle plays an important role in cardiac function. Recently, left atrio-ventricular coupling index (LACI) has emerged as a new cardiac magnetic resonance (CMR-) based imaging parameter. It is defined as the ratio between the LA and LV end-diastolic volume. LACI has been demonstrated to provide incremental prognostic value compared to conventional imaging parameters such as left ventricular ejection fraction (LVEF) in asymptomatic patients without know cardiac disease.
The study aimed to assess the prognostic value of LACI, measured by CMR, with respect to the occurrence of cardiovascular events in patients with CCS.
Methods
We retrospectively analysed patients with CCS who underwent CMR stress testing between 2009 and 2018. To ensure a comprehensive representation of the CCS population, we included patients with varying stages of coronary artery disease: Patients with at least 50 % stenoses that were deemed hemodynamically non-significant on stress CMR as well as patients with a history of CABG were included. LACI as well as global longitudinal strain (GLS) were measured for each patient.
Left atrioventricular coupling index was defined as the ratio of the CMR-derived LA end-diastolic volume to the LV end-diastolic volume measured in the same end-diastolic phase and was expressed as a percentage.
Primary endpoint was defined as the occurrence of MACE (cardiac death and non-fatal myocardial infarction (STEMI and non-STEMI)). Secondary endpoints were defined as hospitalisation for heart failure, percutaneous coronary intervention (PCI), CABG, and all-cause death. Univariate and multivariate hazard ratios (HR) for primary and secondary endpoints were calculated using Cox proportional regression models.
Results
In the cohort of 613 patients, 81 patients (13.2 %) experienced MACE after a median follow-up of 5.6 (IQR 4.2 - 6.8) years. LACI was not significantly associated with MACE (HR 1.01; 95 % CI 0.99 – 1.01, p = 0.07), but was significantly associated with hospitalisation for heart failure (HR 1.02, 95 % CI 1.01 – 1.03, p <0.0001) and all-cause death (HR 1.02, 95 % CI 1.01 – 1.03, p <0.0001). After adjusting for clinical parameters, such as age, as well as standard imaging parameters, such as LVEF and GLS, the association remained significant for heart failure hospitalisation and all-cause death for LACI (HR 1.03; 95 % CI 1.01 – 1.04, p < 0.0001 and HR 1.01; 95 % CI 1.00 – 1.02, p = 0.0199, respectively). The optimal LACI cutoff for identifying high-risk patients concerning heart failure hospitalisation was 31.2 %.
Conclusion
LACI provides incremental prognostic value beyond traditional cardiovascular risk factors and imaging parameters, defining it as a potentially valuable, time-efficient marker for predicting heart failure hospitalization and all-cause death in CCS patients.