Left atrial functional assessment and mortality in patients with severe aortic stenosis with sinus rhythm

Abstract

Background Aortic valve stenosis (AS) is the most common primary valvular heart disease leading to surgical or percutaneous aortic valve replacement (AVR) in Europe and its prevalence keeps growing. While other risk factors in severe AS are well documented, little is known about the prognostic value of left atrial (LA) function in AS. Our aim is to clarify the relationship between LA function measured at severe AS diagnosis (evaluated by means of volumetric assessment) and all-cause mortality during follow-up. Methods We retrospectively evaluated patients diagnosed with severe AS for the first time at our echocardiography laboratory. We evaluated LA reservoir, conduit and pump function by measuring LA volumes at different timings of cardiac cycle. Treatment strategy was decided according to heart team consensus and patient decision. We divided patients into groups according to terciles of LA reservoir, conduit and pump function. Primary outcome was defined by the occurrence of all-cause mortality during follow-up. Results A total of 408 patients were included in the analysis, with a median follow-up time of 45 months (interquartile range 54 months). 57.9% of patients underwent AVR and 44.9% of patients registered the primary outcome during follow-up. Left atrial emptying fraction (LAEF) was the best LA functional parameter and the best overall parameter in discriminating primary outcome (AUC 0.845, 95%CI 0.81–0.88, P < 0.001). After adjustment for clinical, demographic and echocardiographic variables, cumulative survival of patients with LAEF < 37% and LAEF 37 to 53% relative to patients with LAEF ≥54% remained significantly lower (HR 13.91, 95%CI 6.20–31.19, P < 0.001 and HR 3.40, 95%CI 1.57–7.37, P = 0.002, respectively). After adjustment for AVR, excess risk of LAEF < 37% and LAEF 37 to 53% relative to LAEF ≥54% remained significant (HR 11.71, 95%CI 5.20–26.40, P < 0.001 and HR 3.59, 95%CI 1.65–7.78, P = 0.001, respectively). Conclusions In patients with a first diagnosis of severe AS, LA function, evaluated by means of volumetric assessment, is an independent predictor of all-cause mortality and a more potent predictor of death compared to classical severity parameters. These data can be useful to identify high-risk patients who might benefit of AVR.

Cardiac Imaging for the Assessment of Left Atrial Mechanics Across Heart Failure Stages

“…Moreover, LA longitudinal strain parameters were inversely correlated with the worsening of NYHA class. These findings are consistent with the greater ability of LA mechanics in predicting prognosis when compared with LV mechanics analysis ( 34 , 152 , 153 ). Galli et al ( 35 ) demonstrated that LA reservoir function (<21%) is predictive of major adverse cardiac events and HF in 128 symptomatic and asymptomatic patients with severe AS, while LV function parameters (ejection fraction and global longitudinal strain) are not.…”

Quantification of left atrial function and geometry by cardiac magnetic resonance imaging in patients with severe aortic stenosis

“…Both of them were also notably associated with AS severity [34]. Additionally, Ferreira et al have shown that defective LA emptying fraction was a strong predictor for all-cause mortality [35].As for LA strain, studies have shown that LA strain was related to LV dysfunction and AS severity, being also an independent predictor for HF hospitalization, all-cause mortality, and new-onset atrial brillation, regardless of LA dilation [36,37]. Recently, Kim et al have conducted a CMR study in which they have suggested that LA peak longitudinal strain might predict cardiovascular events in AS [38], but several studies have shown that traditional CMR methods might have questionable reliability, requiring further adjustments [39].…”

The influence of transcatheter aortic valve replacement on left atrial mechanics: a systematic review and meta-analysis

“…LA geometry and function are well-described prognostic discriminators for multiple left heart conditions. For patients with aortic stenosis, both LA size and function have demonstrated independent incremental prognostic information 32 , 33 ; however, current studies quantifying LA function using strain imaging are limited in both number and sample size. Moreover, the independent prognostic value of LA functional recovery following TAVR and whether intervention at an earlier stage may afford biologically plausible protection from the known consequence of adverse LA remodelling, such as new onset AF, are yet to be demonstrated in large prospective cohorts.…”