LVAD Survival May Be Predicted by Preoperative Lymphopenia

Purpose In patients with an established diagnosis of heart failure, lymphopenia can predict survival up to 1 year after measurement. Lymphocytes can be depleted through enteric losses secondary to splanchnic congestion or through exaggerated physiologic stress response. However, the prognostic role of lymphopenia in the outcome of LVAD patients has not been explored. We sought to examine the impact of lymphopenia on all-cause mortality in this population over a 24-month period post implantation. Methods At a single center, 170 patients received LVAD therapy between June 2011 and July 2018. 99 of these patients met criteria for lymphopenia on admission as defined as an absolute lymphocyte count (ALC) 4800/μL and nine with incomplete data. A Kaplan-Meir plot and log-rank statistics were used to compare survival across patient groups with and without lymphopenia. The association between lymphopenia and 24-month all-cause mortality was examined via unadjusted and adjusted cox models. Results In the lymphopenic group, mean ALC was 909.6± 331.9 and median (Interquartile range) of 910 (684.0 - 1164.8) versus 2073.6±501.1 and 1941.0(1679.5 - 2340.0) in the non-lymphopenic group. 24-month mortality was significantly higher in the lymphopenic group (Log-Rank p=0.009). On Cox-modelling, the lymphopenic patients had worse unadjusted survival [HR= 2.14 (1.19 - 3.82) (p=0.01)] and adjusted survival [2.01 (1.12 - 3.60) (p=0.02)] when age, race, gender, eGFR, INTERMACS category, serum sodium and LVEF were adjusted for. Conclusion Worse survival was seen in LVAD patients with lymphopenia at up to 24-months post procedure. Lymphocyte levels may be an important prognostic indicator and therapeutic target with future immune modulator therapy.