Left Atrial Mechanical Function Predicts Postoperative AF in Patients with Rheumatic Mitral Valve Disease Who Underwent Mitral Valve Surgery

Objective: Postoperative atrial fibrillation (PoAF) is a common complication after surgical mitral valve replacement. Late PoAF is independently associated with long-term mortality. This study aimed to test the utility of preoperative left atrial mechanical function as a predictor of early and late PoAF in clinical practice. Methods: Patients (N = 150) with a rheumatic mitral valve who underwent mitral valve replacement with or without tricuspid valvuloplasty and who were in stable sinus rhythm were included. Baseline characteristics and transthoracic echocardiographic assessment information on the day before surgery were collected. Em, Em´, and Ei´ indicate early diastolic peak velocity of the mitral valve, early diastolic velocity at the lateral wall of the mitral annulus, and early diastolic velocity at the interventricular septal annulus, respectively. Results: Early PoAF was present in 59 of 150 patients (39.3%), and 32 of 150 patients (21.3%) developed late PoAF within 1 year after surgery. Among all of the variables examined, age, diabetes, early mitral filling velocity (Mitral E), left atrial mechanical function (Mitral A), Em/Em´, Em/Ei´, and mitral transvalvular gradient showed a significant correlation with PoAF. Only age, Mitral A, and mitral transvalvular gradient showed strong, significant correlations with the occurrence of late PoAF. In a multivariate analysis, predictors of late PoAF recurrence included early PoAF and Mitral A. Conclusion: Routine evaluation of Mitral A is feasible and useful to predict early and late PoAF in patients with a rheumatic mitral valve undergoing surgical mitral valve replacement.

LEFT ATRIAL MECHANICAL FUNCTION AND ITS DISORDERS AFTER PULMONARY VEIN ANTRUM ISOLATION

The article presents new insights into the left atrial mechanical function, its main components and remodeling mechanisms after pulmonary vein antrum isolation. Left atrium is a cardiac chamber that transports blood. Being a complex «organ» both in anatomical and functional terms, it responds to hemodynamic derangements, the impact of humoral and vegetative factors. Structural, mechanical and electrical remodeling of the left atrium play a key role in the arrhythmogenesis of atrial fibrillation, as well as in the mechanism of arrhythmia maintenance. Left atrial mechanical dysfunction following catheter ablation of atrial fibrillation significantly affects intracardiac hemodynamics, worsens patients' well-being, and increases the risk of thromboembolic complications both in the immediate and long-term postoperative period.