ABSTRACT
Background: Intravenous (IV) and subcutaneous (SC) Immunoglobulin G (IG) replacement products are in wide use in patients with primary antibody deficiency syndrome (PAD). There is limited data on the levels of anti-SARS-CoV-2 spike antibodies in IG products or their ability to neutralize emerging SARS-CoV-2 variants. There is lack of data on the impact of IG therapy on serum anti-SARS-CoV-2 spike or neutralizing antibody titers in PAD patients. Method(s): We measured anti-SARS-CoV-2 anti-spike antibody levels and neutralizing titers against historical (WA1/2020) and variant (B.1.617.2 [Delta] and BA.1 [Omicron]) strains in 158 lots of 6 different IG products, collected between August 2021 to April 2022 and manufactured between December 2019 to December 2021. IG products were compared to serum from 20 healthy donors vaccinated with 2 doses of Pfizer-BioNTech mRNA vaccine. Serum anti-spike antibody level and SARS-CoV-2 neutralization activity were measured in 27 PAD patients treated with the tested IG products. Result(s): Anti-spike antibody titers started to increase in products manufactured in March 2021 and reached peak level, comparable to vaccinated healthy donors, in products manufactured in August 2021 (Fig. 1). The neutralization activity against WA1/2020 and Delta strains showed a similar pattern (Fig. 2). However, 95% of the tested products had no neutralization activity against Omicron. Until November 2021, IVIG products infused to patients in the study had anti-spike titers comparable to unvaccinated healthy donors (Fig. 3). Beginning in February 2022, IVIG products had anti-spike titers comparable to vaccinated healthy controls. Concurrent with a rise in anti-spike antibodies in IG products, PAD patients showed an increase in serum levels of anti-spike antibody and neutralizing activity against WA1/202 and Delta but not against Omicron variants. Testing of immunoglobulin replacement products neutralization activity against emerging variants BQ.1 and BQ.1.1 is underway.[Formula presented][Formula presented][Formula presented] Conclusion(s): The anti-SARS spike antibody and neutralization activity of IVIG products lags after the emergence of COVID-19 variants and currently have poor activity against Omicron strain. Because of the protracted manufacturing process, this is expected to be an ongoing challenge. As variants emerge, clinicians should consider additional means of protection for PAD patients such as vaccination, or prophylaxis with monoclonal antibodies.Copyright © 2023 Elsevier Inc.
ABSTRACT
Background: Transcatheter aortic valve implantation (TAVI) is now guideline treatment for severe aortic stenosis in patients over the age of 80 years. Objective: We report the initial experience of the first 50 patients for the Tasmanian TAVI Service at the Royal Hobart Hospital established during the COVID-19 pandemic. Methods: The records of patients undergoing TAVI with a balloon-expandable device between June 2020 and March 2021 at the Royal Hobart Hospital were reviewed. We report the procedural success and outcome, including major adverse events and haemodynamic results at the 30-day follow-up. Results: Mean age was 83.2±0.7 and mean EuroSCORE II and Society of Thoracic Surgeons’ scores were 5.6%±0.4% and 6.2%±1.0%, respectively;18% had undergone prior cardiac surgery. Successful transfemoral deployment of the valve was achieved in all patients. The cumulative stroke and mortality rates at 30 days were 0%. The minor vascular complication rate was 3.8%, with no major vascular complications, as per the Valve Academic Research Consortium-2 (VARC-2) criteria. No/trivial paravalvular aortic regurgitation (pAR) was observed in 79%, with 21% mild pAR. The mean AVA (cm2) increased from 0.73 to 2.1, with a subsequent mean reduction in mean gradient (mmHg) from 40 to 10. Post-TAVI permanent pacemaker rate was 12%. Median length of hospital stay was 1.48 days. Conclusion: TAVI is now readily accessible locally for Tasmanians deemed suitable for intervention as per the state-wide heart team. Early results are excellent and indicate that TAVI is being used appropriately, according to current national and international guidelines.