ABSTRACT
Introduction: The risk of Severe Acute Respiratory Syndrome - Coronavirus-2 (SARS-CoV-2) infection and mortality is higher in heart transplant (HT) recipients compared to immunocompetent individuals. The impact of years since transplant on clinical course risk is unknown. We evaluated the differences in clinical phenotypes and outcomes according to years since transplant in HT recipients with active SARS-CoV-2 infection. Method(s): Consecutive HT recipients from our National Transplant Centre with confirmed SARS-CoV-2 between April 2020 and March 2022 were enrolled in this retrospective observational study. Patients were stratified into 2 groups: <5 years after HT (Group A) and >/= 5 years after HT (Group B). Result(s): A total of 63 HT recipients were enrolled [median age 56 (41,66) years, 32% female] with 33% of patients (n=21) assigned to Group A, and 67% (n=42) to Group B. In Group B patients, the prevalence of diabetes mellitus and cardiac allograft vasculopathy was significantly higher compared to those in Group A. Meanwhile, Group A patients were more likely to have a history of neutropenia prior to SARS-CoV-2 infection and were more frequently taking maintenance steroids and antimetabolite immunosuppressants (Table 1). Those recipients less than 5 years since HT were also significantly more likely than those >5 years out to develop the infection despite a 3rd dose of COVID vaccine (60% vs 31%, p 0.03).During the active infection, Group A recipients more frequently developed neutropenia (73% vs 27%, p 0.01), and trended towards higher rates of hospitalizations (57% vs 32%, p 0.06). Notably, none of the patients in Group A required mechanical ventilation compared to just under 10 % (n=4) of those in Group B. Further, no Group A patients died during the active infection hospitalization compared to 14% (n=6) of those in Group B. Conclusion(s): In HT recipients, years since transplant is a simple, clinically useful parameter stratifying outcomes after SARS-CoV-2 infection. While patients with less than 5 years since transplant are more likely to develop infection despite booster vaccination and require hospitalization, greater number of years since transplant was associated with more severe consequences during hospitalization.Copyright © 2022
ABSTRACT
28 Figure 1a) Frequency of a detectable antibody response after each vaccination for 80 heart transplant recipients, b) Interval change in anti-spike antibody titres between the 2nd ChAdOx1 nCoV-19 vaccine and the 3rd dose mRNA (BNT162b2) booster vaccine.[Figure omitted. See PDF]Conclusions/ImplicationsHeart transplant recipients who received 2 doses of the ChAdOx1 nCoV-19 viral vector vaccine and a mRNA booster vaccine failed to develop a detectable antibody response in 44% of cases. These findings highlight the importance of maintaining protective measures for transplant recipients, particularly those on more intensive immunosuppressive regimens, both at a personal and public health level, as well as investigating additional strategies to protect this vulnerable patient cohort.