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.

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.

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.

Respiratory gating algorithm helps to reconstruct more accurate electroanatomical maps during atrial fibrillation ablation performed under spontaneous respiration.

PURPOSE: Electroanatomical mapping is a useful tool during the ablation of atrial fibrillation. Respiratory movement might influence the mapping accuracy and merging. This study aims to investigate the effect of respiratory gating on the accuracy of magnetic-field-based electroanatomical mapping under spontaneous respiration. METHODS: Fifty-one consecutive patients (35 male, aged 30-78 years) who underwent left atrial radiofrequency catheter ablation due to atrial fibrillation were included. Electroanatomical mapping was performed with CARTO 3 System under conscious sedation. Respiratory gating was achieved with the AccuResp algorithm (Biosense Webster). Average surface match and maximum distance of the pre-acquired and electroanatomical maps, as well as left atrial volume, were recorded with and without respiratory gating after merging. RESULTS: The average surface match of the electroanatomical map with the left atrial reconstruction was significantly better with respiratory gating than without using the algorithm (3.81 ± 1.09 vs 4.11 ± 1.61 mm, p = 0.0119). It was not dependent of the rhythm during mapping or the image modality used for left atrial reconstruction. The maximal distance between the two maps did not depend on the use of the algorithm (19.81 ± 6.24 mm for gated and 20.87 ± 7.99 mm for non-gated, p = 0.3161). Left atrial volume of the map was significantly lower when using the respiratory compensation module (106.3 ± 31.6 vs 127.0 ± 36.4 ml, p < 0.0001) and showed a significant correlation with the pre-recorded 3D reconstruction volumes (r = 0.66, p < 0.0001). CONCLUSIONS: The use of the novel respiratory gating algorithm might improve the accuracy of electroanatomical mapping during left atrial ablation under conscious sedation. The possible impact on the effectiveness of the ablation needs to be further evaluated.