Left atrial booster-pump function as a predictive parameter for new-onset postoperative atrial fibrillation in patients with severe aortic stenosis

Abstract

Postoperative atrial fibrillation (POAF) is associated with increased risk of embolic events and heart failure, but its associated factors remains unknown. Left atrial (LA) subclinical mechanical dysfunction caused by the acute stress of surgery may be clinically manifested as POAF. The purpose of our study was therefore to test the hypothesis that preoperative LA subclinical myocardial dysfunction is a potential predictor of development of POAF in patients with aortic stenosis (AS). We studied 27 patients with severe AS undergoing aortic valve replacement (AVR) with left ventricular (LV) ejection fraction of 63 ± 11 %. All patients were in sinus rhythm and had no history of atrial fibrillation (AF). LA reservoir (SR-LAs), conduit (SR-LAe), and booster-pump (SR-LAa) functions were determined as the averaged global LA speckle-tracking longitudinal strain rates from apical four- and two-chamber views. POAF, defined as any episode of AF within 30-day after AVR, was observed in 15 patients (56 %). There were no differences in clinical characteristics, LA and LV volumes, and global LV function between patients with and without POAF. Multivariate logistic regression analysis identified SR-LAa as the only independent predictor of POAF. Furthermore, SR-LAa >0.79 s(-1) predicted POAF with 60 % sensitivity, 92 % specificity, and area under the curve of 0.828 (p < 0.0001). Of the 15 patients with POAF, one developed paroxysmal AF during long-term follow-up. In conclusions, SR-LAa helped to detect subtle LA booster-pump dysfunction and was associated with new-onset POAF in patients with severe AS. These findings may be useful for risk stratification and management of such patients.

Usefulness of atrial function for risk stratification in asymptomatic severe aortic stenosis

“…Additionally, increased LA volume has been introduced as an independent predictor of prognosis in these patients [18]. However, the role of atrial function as a contributor to the patients' outcomes has been poorly investigated to date [32]. With the present study, we sought to attain a deeper insight into the risk stratification of asymptomatic AS patients by investigating whether atrial function impairment could actually have any role.…”

“…It is demonstrated that after transcatheter aortic valve implantation or surgical aortic valve replacement, a significant anatomical and functional reverse remodeling of both LV and LA has been detected in terms of reduced LV mass and improved LV and LA longitudinal performance [39][40][41][42]. Moreover, a reduced LA strain has already been associated with the severity of AS and has been identified as a predictor of atrial fibrillation recurrence after aortic valve replacement [32].…”

Prognostic Relevance of Left Atrial Dysfunction in Heart Failure With Preserved Ejection Fraction

“…The prognostic importance of LA pump function in HFpEF is not well known. LA pump function is associated with risk of AF in patients with aortic stenosis 40 and in the general population, 41 but has also been associated with adverse cardiovascular events in hypertensive populations. 42,43 Impaired LA contractile reserve secondary to progressive elevation of LV filling pressure may contribute to HFpEF symptoms, particularly during exercise.…”

Left atrial function: evaluation by strain analysis

“…In a study by Galli et al involving 128 patients with severe AS, reduced LA systolic strain was associated with an increase in all-cause mortality, worsening HF and cardiac hospitalization (89). LA systolic strain was also a predictor of postoperative AF in patients with severe AS undergoing surgery (90).…”