Order of shared first authorship was determined by the temporal order of research contribution and agreed upon by co-first authors. Each co-first author has the right to list themselves first for purposes of their curriculum vitae and biosketch.

Letermovir is a novel agent for the prevention of cytomegalovirus (CMV) infection and disease that, unlike traditional CMV DNA polymerase inhibitors, does not carry the risk of myelosuppression. The purpose of this study was to evaluate the safety, efficacy, and clinical application of letermovir for CMV prophylaxis in heart transplant (HT) recipients. Between November 1, 2019, and October 1, 2021, at a single, tertiary care hospital, 17 HT recipients were initiated on letermovir due to leukopenia while on valganciclovir. Fifteen (88%) had high-risk mismatch (CMV D+/R-). Median time on letermovir was 5 months (interquartile range, 2-8 months.) At the end of the study period, nine of 17 patients (52.9%) were still on letermovir and four of the 17 (23.5%) had successfully completed the prophylaxis window on letermovir and been switched to the pre-emptive strategy. One patient developed clinically significant CMV viremia in the setting of being unable to obtain medication due to insurance barriers but was later successfully restarted on letermovir. One patient was unable to tolerate letermovir due to symptoms of headache and myalgias. Two patients developed lowlevel non-clinically significant CMV viremia and were switched back to valacyclovir. All patients had tacrolimus dosages reduced at time of letermovir initiation to minimize the risk of supratherapeutic tacrolimus concentration. One patient required hospitalization due to symptomatic tacrolimus toxicity. For HT recipients who cannot tolerate valganciclovir, letermovir presents an alternative for CMV prophylaxis. Close monitoring for breakthrough CMV and calcineurin inhibitor levels is necessary. Larger studies are required to further delineate its use and help provide further evidence of its safety and efficacy.

Background: An aging population and improved cancer survivorship have increased the number of individuals with treated malignancy who develop advanced heart failure. The benefits of heart transplantation (HT) in patients with a pretransplant malignancy (PTM) must be balanced against risks of posttransplant malignancy in the setting of immunosuppression. Methods: Adult patients in the United Network for Organ Sharing registry who received HT between January 1, 2010, and December 31, 2020 were included. Trends, patient characteristics, and posttransplant outcomes in HT recipients with PTM were evaluated. Results: From 2000 to 2020, the proportion of HT recipients with PTM increased from 3.2% to 8.2%. From 2010 to 2020, 2113 (7.7%) of 27 344 HT recipients had PTM. PTM was associated with higher rates of 1-year mortality after HT (11.9% versus 9.2%; adjusted hazard ratio, 1.25 [95% CI, 1.09–1.44], P =0.001), driven by increased mortality in patients with hematologic PTM (adjusted hazard ratio, 2.00 [95% CI, 1.61–2.48]; P <0.001). For recipients who survived the first year, 5-year survival was similar between patients with and without PTM. Rates of malignancy at 5-years posttransplant were higher in the PTM group (20.4% versus 13.1%; adjusted hazard ratio, 1.57 [95% CI, 1.38–1.79], P <0.001). Conclusions: Prevalence of PTM in HT recipients nearly tripled over the past 2 decades. Patients with hematologic PTM were at increased risk of early mortality after HT. Patients with PTM were also at higher risk for posttransplant malignancy. Guidelines that reflect contemporary oncological care are needed to inform care of this heterogenous and expanding group of individuals.

Background: During the height of the coronavirus disease 2019 (COVID-19) pandemic in New York City, COVID-19 hospitalization was associated with high mortality. It is unknown how palliative care was utilized in this context. Objectives: To describe the frequency of palliative care consultation and its association with end-of-life care for deceased patients with COVID-19. Methods: Adults who were admitted to our institution between February 23, 2020, and April 21, 2020, and died from COVID-19 were included. The primary outcome was the frequency of palliative care consultation. Secondary analyses included the association of palliative care consultation with code status at the time of death, life-sustaining treatments, mechanical ventilation, invasive procedures, intensive care unit (ICU) admissions, and length of hospital stay. Results: The 203 patients were 61% male with median age 76 (interquartile range [IQR] 67-84) years. Palliative care was consulted for 113 patients (56%). At baseline, they were less independent in instrumental activities of daily living (28 patients, 26.1%, vs. 47 patients, 49.0%, p < 0.01) and had more do-not-resuscitate orders (35 patients, 32.7%, vs. 11 patients, 11.5%, p < 0.01). Palliative care consultation was associated with fewer invasive procedures (0, IQR 0-2, vs. 2, IQR 0-3, p < 0.01), less mechanical ventilation (32 patients, 29.9% vs. 65 patients, 67.7%, p < 0.01), and fewer ICU admissions (33 patients, 30.8% vs. 69 patients, 71.9%, p < 0.01). Palliative care was associated with shorter ICU stays (0 days, IQR 0-4, vs. 4 days, IQR 0-12, p < 0.01), whereas hospital stays did not differ significantly (8 days, IQR 5-12.5, vs. 10 days, IQR 5-16.3, p = 0.15). Conclusion: Palliative care was consulted for roughly half of deceased patients with COVID-19 and those patients were less likely to undergo invasive procedures or life-sustaining treatments and spent less time in the ICU at the end of life.

Background: Leukopenia in the early period following heart transplantation (HT) is not well-studied. The aim of this study was to evaluate risk factors for the development of post-transplant leukopenia and its consequences for HT recipients.Methods: Adult patients at a large-volume transplant center who received HT between January 1, 2010 and December 31, 2020 were included. The incidence of leukopenia (WBC ≤3 × 10 3 /µL) in the first 90-days following HT, individual risk factors, and its effect on 1-year outcomes were evaluated.Results: Of 506 HT recipients, 184 (36%) developed leukopenia within 90-days.Median duration of the first leukopenia episode was 15.5 days (IQR 8-42.5 days). Individuals who developed leukopenia had lower pre-transplant WBC counts compared to those who did not (6.1 × 10 3 /µL vs. 6.9 × 10 3 /µL, p = .02). Initial immunosuppressive and infectious chemoprophylactic regimens were not significantly different between groups. Early leukopenia was associated with a higher mortality at 1-year (6.6% vs. 2.1%, p = .008; adjusted HR 3.0) and an increased risk of recurrent episodes. Rates of infection and rejection were not significantly different between the two groups.Conclusions: Leukopenia in the early period following HT is common and associated with an increased risk of mortality. Further study is needed to identify individuals at highest risk for leukopenia prior to transplant and optimize immunosuppressive and infectious chemoprophylactic regimens for this subgroup.