Seroconversion after SARS-CoV-2 vaccination is protective against severe COVID-19 disease in heart transplant recipients.

BACKGROUND: Heart transplant (HTX) recipients are prone to develop complications after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Vaccination is often ineffective due to weaker immunogenicity. In this high-volume single-center study, we aimed to determine factors influencing seroconversion after vaccination and predictors of severe SARS-CoV-2 infection. METHODS: Two hundred twenty-nine HTX recipients were enrolled. Type of the first two vaccine doses included messenger RNA (mRNA), vector, and inactivated vaccines. We carried out analyses on seroconversion after the second and third doses of vaccination and on severity of infection. Antispike protein SARS-CoV-2 immunoglobulin G (IgG) was measured after the second and third vaccines and serostatus was defined. Effect of the first two vaccine doses was studied on patients who did not suffer SARS-CoV-2 infection before antibody measurement (n = 175). The effectivity of the third vaccine was evaluated among seronegative recipients after the second vaccine (n = 53). Predictors for severe infection defined as pneumonia, hospitalization or death were assessed in all patients who contracted SARS-CoV-2 infection (n = 92). RESULTS: 62% of the recipients became seropositive after the second vaccination. Longer time between HTX and vaccination (odds ratio [OR]: 2.35) and mRNA vaccine (OR: 4.83) were predictors of seroconversion. 58% of the nonresponsive patients became seropositive after receiving the third vaccine. Male sex increased the chance of IgG production after the third dose (OR: 5.65). Clinical course of SARS-CoV-2 infection was severe in 32%. Of all parameters assessed, only seropositivity before infection was proven to have a protective effect against severe infection (OR: 0.11). CONCLUSIONS: We found that longer time since HTX, mRNA vaccine type, and male sex promoted seroconversion after SARS-CoV-2 vaccination in HTX recipients. Seropositivity-but not the number of vaccine doses-seemed to be protective against severe SARS-CoV-2 infection. Screening of HTX patients for anti-SARS-COV-2 antibodies may help to identify patients at risk for severe infection.

Local laboratory-run donor-derived cell-free DNA assay for rejection surveillance in heart transplantation-first six months of clinical experience.

INTRODUCTION: Donor-derived cell-free DNA (dd-cfDNA) is a blood biomarker detecting graft injury with high negative predictive value. While non-invasive strategies for heart transplant (HTx) rejection surveillance are widely adopted in the United States with centralized testing, data on the feasibility of dd-cfDNA assay at the local level are lacking. Here, we report the first 6 months of experience with a local laboratory-run dd-cfDNA assay in the routine clinical surveillance setting. METHODS: Twenty-six HTx patients with stable graft function were transitioned from endomyocardial biopsy-based (EMB) to dd-cfDNA-led rejection surveillance using a commercially available next-generation sequencing-based assay. RESULTS: In the 90 samples analyzed, dd-cfDNA fraction remained continuously low in most patients, thus 88% of surveillance EMBs could be safely avoided. In the case of ≥.25% dd-cfDNA, EMB was performed. There was no missed rejection. CONCLUSION: Our data show the feasibility to analyze dd-cfDNA at the local level and successful implementation of this non-invasive surveillance method into clinical practice, thus considerably reducing the frequency of invasive surveillance EMBs.

Extracorporeal photopheresis in the treatment of cardiac allograft rejection: A single-centre experience.

Despite novel immunosuppressive (IS) protocols, adverse effects of IS drugs continue to have notable negative impact on patient and cardiac allograft survival after heart transplantation (HTx). Therefore, IS regimens with less toxic side effects are sorely needed. We aimed to evaluate the efficacy of extracorporeal photopheresis (ECP) in combination with tacrolimus-based maintenance IS therapy in the treatment of allograft rejection in adult HTx recipients. Indications for ECP included acute moderate-to-severe or persistent mild cellular rejection, or mixed rejection. Twenty-two patients underwent a median of 22(2-44) ECP treatments after HTx. Median duration of ECP course was 173.5(2-466) days. No relevant adverse effects of ECP were noted. Reduction of methylprednisolone doses was safe throughout the ECP course. ECP, used in conjunction with pharmacological anti-rejection therapy, had a successful reversal of cardiac allograft rejection, decreased the rates of subsequential rejection episodes and normalized the allograft function in patients completing the ECP course. Short- and long-term survivals were excellent (91% at 1 and 5 years post-ECP) and comparable to International Society for Heart and Lung Transplantation registry data on HTx recipient overall survival. In conclusion, ECP can be safely used for the treatment and prevention of cardiac allograft rejection in conjunction with traditional IS regimen.

European multicenter study on the real-world use and clinical impact of extracorporeal photopheresis after heart transplantation.

BACKGROUND: Aim of this study was to describe the real-world use of extracorporeal photopheresis (ECP) and assess its impact on clinical outcomes in the modern era of heart transplantation. METHODS: Seven transplant centers from 5 European countries participated in this retrospective, observational, single-arm chart review study. All patients received ECP after heart transplantation in 2015 or later. Data were extracted from medical records between November 2020 and December 2021. RESULTS: Overall, 105 patients were enrolled and followed for an average of 2 years after initiation of ECP. Reasons to start ECP were acute cellular rejection (35.2%), rejection prevention (32.4%), mixed rejection (18.1%), and antibody-mediated rejection (14.3%). Rejection ISHLT grades improved from start to end of ECP treatment in 92% of patients treated with ECP for rejection. Of patients who started ECP to prevent rejection, 88% remained free from any rejection despite a reduction of calcineurin inhibitors. Overall survival was 95%, and no deaths were related to ECP. Safety events occurred in 18 patients, of which 13 experienced complications with venous access. CONCLUSIONS: This study, the largest European ECP study in heart transplantation, demonstrates that ECP can effectively be used to treat different rejection types and to prevent rejection in the modern era of immunosuppression. Patients with rejections who have received ECP have shown high response as measured by histological improvements in ISHLT classification. A high percentage of patients in the prevention group remained free from rejection despite reduction in immunosuppression, in particular calcineurin inhibitors.

Pseudoaneurysm of the ascending aorta: case report of a donor-derived Pseudomonas infection in a heart transplant recipient.

BACKGROUND: Mycotic aortic pseudoaneurysm is a rare complication after heart transplantation (HTX) with remarkable mortality. Intrathoracic infection is a well-documented predisposing factor for this disease. Staphylococcus aureus, Pseudomonas aeruginosa or Candida species are commonly isolated from resected specimens of the pseudoaneurysms. We demonstrate a unique case of mycotic pseudoaneurysm caused by presumably donor-derived Pseudomonas infection in a heart transplant recipient. CASE PRESENTATION: Our 67-year-old male patient treated with diabetes mellitus underwent HTX. The donor suffered from epiglottic abscess and pneumonia with known microorganisms including Pseudomonas, therefore both the donor and recipient received targeted antimicrobial therapy and prophylaxis. Five months after the uneventful HTX, lab test of the asymptomatic patient showed moderate, increasing C-reactive protein level without obviuos source of infection. Chest computed tomography showed a large (90 mm) saccular dilatation of the tubular portion of ascending aorta. Urgent surgical intervention identified a pseudoaneurysm, histological examinations and cultures of the resected aorta verified Pseudomonas aeruginosa aortitis, while all blood cultures remained negative. Retrospective interrogation of other transplanted organs of the donor supported donor-derived infection as the transport fluid of the right kidney grew Pseudomonas. The patient received 3 weeks of ceftazidime followed by 7 months of oral ciprofloxacin therapy. One year after the operation the patient was asymptomatic with normal inflammatory markers. CONCLUSIONS: Donor-derived infection is a rare but potential cause of aortitis. Early diagnosis, surgical intervention and adjuvant antibiotic therapy seem to be the keys to successful management of mycotic pseudoaneurysms after HTX.