Winter LVAD implantation is associated with adverse clinical outcomes

Background: The seasonal variation of incidence and severity of heart failure is well known. However, the impact of seasonal variation on clinical outcomes following left ventricular assist device (LVAD) implantation remains unknown. Methods: We retrospectively reviewed consecutive patients who received LVAD implantation between January 2014 and December 2016 along with their first year of post-implant outcomes. Clinical outcomes were compared between those with winter LVAD implantation (between October and March) and those with non-winter LVAD implantation. Results: 168 patients with a median age of 57 years and 130 males were included. There was no seasonal difference in the number of LVAD implantations. One-year survival free from major adverse events was significantly lower in the winter implant group (n= 88) compared to the non-winter group (n= 80) (44% vs 61%) with an adjusted hazard ratio of 1.81 (95% confidence interval 1.11-2.90,p= 0.014), largely due to a higher rate of heart failure readmission in the winter implant patients (incidence rate ratio 2.29, 95% confidence interval 0.89-5.84). Conclusion: Patients who underwent LVAD implantation during the winter season had a higher heart failure readmission rate. A detailed mechanism and therapeutic strategy given our findings warrant further investigation.