Left Atrial Reverse Remodeling in Patients Supported With Durable Left Ventricular Assist Devices and Clinical Implications.

Background: The left atrium (LA) maintains a dynamic interaction with the left ventricle (LV). LA forward and reverse remodeling affect prognosis in patients with chronic heart failure. We examined LA reverse remodeling in patients supported with LV assist devices (LVADs) and investigated a potential impact on clinical outcomes.

Methods: Consecutive patients with advanced heart failure receiving durable, continuous-flow LVADs were prospectively evaluated (n=263). After excluding patients with unavailable echocardiographic data, 241 patients were studied. Echocardiographic assessment was performed pre- and serially post-LVAD implantation. We assessed LA and LV structure and function and their association, and the impact of LA reverse remodeling on all-cause mortality, LVAD-related adverse events, and atrial fibrillation (AF).

Results: Most patients were male, White, with a mean age of 56±15 years. Forty-four percent had underlying ischemic cardiomyopathy, and 65% were profile 1 to 3 as per the Interagency Registry for Mechanically Assisted Circulatory Support, with a mean LV ejection fraction of 19±7%, and end-diastolic diameter of 6.7±1.1 cm pre-LVAD. LA structure and function improved by 1 month on LVAD support and remained improved by 12 months, as evidenced by LA volumes, emptying volumes, emptying fractions, and strain parameters. LA changes were shown to be associated with LV structural and functional changes. The magnitude of LA reverse remodeling was associated with all-cause mortality, but not cerebrovascular accident/transient ischemic attack, LVAD thrombosis, or late right heart failure rates by 12 months on LVAD support. Of 46 patients with AF pre-LVAD, 28 (61%) converted to sinus rhythm, and 18 (39%) remained in AF during serial echocardiographic assessment.

Conclusions: LA structure and function improved early post-LVAD support, showed stability of improvement during follow-up, and were associated with simultaneous LV changes. Implications on all-cause mortality and AF might inform the care of heart failure patients being considered for advanced therapies, as well as the broader population of patients with heart failure and concomitant AF undergoing pharmacological unloading.