Single Center Experience with Successful Left Ventricular Assist Device Explantation Following Myocardial Recovery

Abstract

Purpose: Hyponatremia is common in patients with heart failure (HF) and is associated with a worse prognosis. The change in sodium and the prognostic value of sodium in HF patients receiving a ventricular assist device (VAD) has not been established. Methods: A single center retrospective study included 100 consecutive patients who received a continuous-flow VAD from 2007 to 2012. Hyponatremia was defined as a sodium level < 135 mEq/L. Sodium levels were examined preoperatively, early (2 weeks), and late (1 year) after VAD implantation. Outcomes of patients who experienced early persistent or new onset hyponatremia were compared to patients who had normal sodium after VAD surgery. Results: Mean age was 62±12 years. 83% of patients were male and 53% had an ischemic etiology. Prior to VAD implant, 55% of patients had hyponatremia. Mean sodium in patients who were hyponatremic prior to VAD was 130±3.5 mEq/L compared to 138±2.5 mEq/L in patients with normonatremia (p< 0.0001). The estimated improvements of sodium levels overtime after VAD implantation using a mixed-effect model with unstructured covariance were 8.37±0.69 mEq/L for the hyponatremic group and 0.66 ±0.62 mEq/L for the normonatremic group (p< 0.0001). 40% of patients had persistent or new hyponatremia 2 weeks after VAD implant while 55% of patients were normonatremic. During 1-year follow-up, there was no difference in Kaplan-Meier time to event for death, 30-day HF rehospitalization, or new onset right ventricular failure between the 2 groups (p= 0.75). Conclusion: In hyponatremic HF patients who received a VAD, the sodium level increased significantly. Persistent hyponatremia early after VAD implantation did not predict worse long-term outcomes.