Sub-acute Effects of Vaccination With a Messenger RNA-based Vaccine against Coronavirus Disease 2019 on Elderly Japanese Patients with Cardiac Disorder
Background: The incidence of acute myocarditis as a sub-acute side effect after vaccination with an mRNA- based vaccine against Coronavirus Disease 2019 (COVID-19) in elderly patients with cardiac dysfunction is unknown. This study assessed adverse cardiac events following vaccination.
Methods: This observational study evaluated all- cause mortality and deterioration of heart failure in 100 Japanese patients who underwent vaccination with an mRNA-based vaccine against COVID-19. Heart failure status was assessed using the Brain Natriuretic Peptide (BNP) ratio, for which the BNP or N Terminal (NT)-pro BNP values were divided by their Upper Normal Limits (UNL). Deterioration was assessed based on changes in the BNP ratio; values (i.e., post-BNP levels minus pre-BNP levels) ≥ 10-fold higher than the UNL denoted significant increment.
Results: The BNP ratio increased from 4.5 (Interquartile range: 1.5-13.6) to 5.9 (Interquartile range: 1.8-19.5) after vaccination (P<0.01). After the first vaccination (Follow-up: 20-222 days), six patients expired and 15 patients exhibited significant increment of the BNP ratio; these patients had a pre-BNP ratio ≥ 4-fold higher than the UNL. Forty-five patients with pre-BNP ratio <4-fold higher than the UNL did not expire or show significant increase in the BNP ratio. The pre-BNP ratio was reliable in predicting cardiac deterioration (Crude Hazard Ratio: 1.02; 95% Confidence Interval (CI): 1.01-1.03; P<0.01).
Conclusion: A BNP ratio ≥ 4-fold higher than the UNL was associated with a high risk of death in elderly patients after vaccination against COVID-19. The BNP ratio may be useful for assessing the cardiac status of elderly patients in this setting.