COVID-19 Vaccination Safe, Lowers Risk of Infection in Heart Transplant Recipients

New findings suggest patients with orthotopic heart transplant (OHT) who are infected with SARS-CoV-2 are at greater risk of severe infection and death in comparison to immunocompetent individuals, making COVID-19 vaccination an important priority.

In fact, COVID-19 vaccination had associations with fewer symptomatic COVID-19 infections, hospitalizations, and deaths and no heart transplant-specific adverse events.

“In light of more infectious COVID-19 variants and ongoing high rates of transmission, COVID-19 vaccination for all OHT recipients is of paramount importance,” wrote study author Laura L. Peters, DNP, FNP, School of Medicine, University of Colorado.

Previous data report SARS-CoV-2 infection in heart transplant recipients is associated with a high case fatality rate ranging from 10% to 35% and hospitalization rate ranging from 50% to 60%. Moreover, among solid organ transplant recipients who received the mRNA vaccines, an antibody response was only found in 14% - 17% following the first dose and 48% - 51% after the second dose.

Although the study reported the vaccine appeared to be safe, the current study sought to assess the safety and effectiveness of COVID-19 vaccination in a large cohort of OHT recipients. A single-center retrospective case-control study of 482 adult recipients of OHT was conducted from March 2020 - through January 2022, according to study investigators.

They excluded a total of 46 OHT recipients who were infected with COVID-19 from March 2020 - January 2021, as they were infected before the availability and time frame for completion of the vaccine series. Then, beginning in January 2021, the remaining 436 OHT recipients were divided into a vaccinated or unvaccinated group.

The primary outcomes were identified as the number of COVID-19 infections and COVID-19-related hospitalizations, intensive care unit (ICU) admissions, and deaths between vaccinated and unvaccinated adult recipients of OHT.

Of the 436 patients included in the study, 106 patients were infected with COVID-19 at a median time after transplant of 11.4 years. Data show the mean age was 54 years, consisting of 303 (69.5%) men and 133 (30.5%) women.

From the 366 patients in the vaccinated cohort, there were 72 COVID-19 infections (19.7%) with 15 hospitalizations (4.1%), 4 ICU admissions (1.1%), and 3 deaths (0.8%). Then, from the 70 patients in the unvaccinated cohort, there were 34 COVID-19 infections (48.6%), 10 hospitalizations (14.3%), 3 ICU admissions (4.3%), and 3 deaths (4.3%).

The vaccinated cohort of patients with OHT had a lower risk of COVID-19 infection (risk ratio [RR], -.41; 95% CI, 0.30 - 0.56), hospitalization (RR, 0.29; 95% CI, 0.14 - 0.61), and death (RR, 0.19; 95% CI, 0.05 - 0.82).

Peters and colleagues noted there was no echocardiographic evidence of graft dysfunction, clinically significant rejection, or allosensitization at 6 months after receipt of the COVID-19 vaccine.

“Despite data suggesting that patients receiving solid organ transplant have a less robust antibody response to COVID-19 vaccines and the need for booster doses, this large observational study shows that COVID-19 vaccination is associated with fewer symptomatic SARS-CoV-2 infections, hospitalizations, and deaths,” Peters concluded.

The study, “Association of COVID-19 Vaccination With Risk of COVID-19 Infection, Hospitalization, and Death in Heart Transplant Recipients,” was published in JAMA Cardiology.