Prognostic significance of cardiovascular magnetic resonance advanced atrial parameters in chronic significant aortic regurgitation

Asymptomatic significant aortic regurgitation (sAR) presents a clinical challenge regarding optimal timing for aortic valve replacement (AVR). Current guidelines rely on left ventricular (LV) dimensions and ejection fraction for decision-making. However, early markers of myocardial damage are needed to improve prognostic accuracy. This study aimed to assess the prognostic significance of left atrial (LA) strain parameters evaluated by cardiac magnetic resonance feature tracking (CMR-FT) in asymptomatic patients with chronic sAR not meeting established surgical criteria.

Between 2013 and 2023, asymptomatic patients with moderate to severe sAR were retrospectively included. Exclusion criteria encompassed patients meeting AVR criteria per 2021 ESC Guidelines. CMR was performed using a 1.5-Tesla scanner. LA strain analysis was conducted using CMR-FT. The primary composite endpoint included allcause mortality and hospital admission due to decompensated heart failure. Statistical analysis involved univariate and multivariate Cox proportional hazards regression models. The study included 111 sAR patients and 40 age-matched controls. During a median follow-up of 32 months, 30 patients (27 %) experienced the composite endpoint. LA reservoir strain was significantly lower in sAR patients compared to controls (15.6 % vs. 21 %, p < 0.001). Multivariate analysis revealed LA reservoir strain as an independent predictor of events (p = 0.015), even after adjusting for LV ejection fraction and regurgitant fraction.

LA reservoir strain assessed by CMR-FT is an independent predictor of major events in asymptomatic sAR patients, outperforming traditional prognostic factors. This parameter may aid in identifying higher-risk patients who could benefit from closer surveillance, more tailored follow-up strategies, and earlier consideration of intervention when integrated with other established clinical and imaging markers.