[ad_1]
Scientists at the University of Ottawa, Canada, recently estimated the prevalence of myocarditis / pericarditis in people recently immunized with 2019 mRNA-based coronavirus disease vaccines (COVID-19). The analysis reveals a prevalence of 10 cases of myopericarditis per 10,000 doses of vaccine. The study is currently available on the medRxiv* preprint server.
Background
The recent COVID-19 outbreak caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has placed a heavy burden on the health care system of many countries, with more than 228 million infections and 4, 69 million reported deaths. COVID-19 vaccines have been developed in record time to control and reduce the spread of the pandemic. As of September 20, 2021, more than 5.9 billion doses of vaccines had been administered worldwide, or 76 doses per 100 people.
Among the COVID-19 vaccines currently available, mRNA-based vaccines have shown high efficacy against SARS-CoV-2 infection and serious illness in clinical trials and real world setups. However, according to the report of the World Health Organization (WHO) Vaccine Safety Committee, a small proportion of individuals, especially men, can develop myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the heart). pericardium) shortly after receiving COVID-19 mRNA vaccines.
In the United States, the prevalence of myopericarditis in vaccinated subjects aged 16 to 24 years has been estimated to be higher than expected.
The present study was conducted to identify cases of myocarditis / pericarditis in people recently vaccinated in Ottawa.
Study design
Scientists analyzed the electronic health record to identify all patients who were admitted to an Ottawa hospital between June and July 2021 with a suspected diagnosis of vaccine-induced myocarditis / pericarditis.
They diagnosed the disease based on the clinical presentation, electrocardiogram (ECG) / echocardiogram (echo) and serial troponin results, and further confirmed the diagnosis using imaging. Cardiovascular magnetic resonance (CMR).
To estimate the prevalence of myocarditis / pericarditis, they collected information from the Ottawa Public Health Agency on the total doses of mRNA vaccine administered in the Ottawa area during the study period. .
Important Notes
A total of 32 patients with vaccine-related myocarditis / pericarditis were identified during the study period. The average age group of patients was 33 years old, and the majority were men. Symptoms developed after the second dose of vaccine in 27 patients and after the first dose of vaccine in only 5 patients. The most frequently reported symptoms were chest pain, shortness of breath, fever and chills.
The average time between the last vaccination and the onset of symptoms was 1.5 days. Regarding vaccine types, Pfizer / Moderna mRNA vaccines were identified as the most common combination, followed by Moderna / Moderna. A combination of AstraZeneca / Moderna was only identified in two patients.
At the time of admission, 22 patients had abnormal ECG results, including diffuse ST segment elevation with PR depression or T wave inversion. However, in 10 patients, the ECG results were normal.
Prevalence of myocarditis / pericarditis
During the study period, a total of 32,379 doses of Pfizer and Moderna vaccines were administered topically. Based on the total vaccine doses, the estimated prevalence of myocarditis / pericarditis was 10 cases per 10,000 vaccine doses. Estimates made separately for each vaccine type revealed that the prevalence of myocarditis / pericarditis in Pfizer and Moderna vaccinees was 4 and 16 cases per 10,000 vaccines, respectively.
Clinical course of myocarditis / pericarditis in hospital
Of 32 patients, 30 were admitted to hospital for clinical observation. Two were followed on an outpatient basis. The mean hospital stay was 4 days. The majority of patients have been treated empirically with aspirin and colchicine, and none of them required steroids or other types of immunosuppressants. In all patients, symptoms resolved shortly after standard treatment. No adverse cardiac events or arrhythmias were observed during the hospital stay.
Based on the results of the CMR, 18 patients were identified with myocarditis, 10 with myopericarditis and 2 with pericarditis. Although the mean left ventricular ejection fraction was 57% in most patients, nine presented with mild left ventricular dysfunction with an ejection fraction below the normal threshold of 55%. Unsupported non-syncopal ventricular tachycardia was observed in a single patient.
Importance of the study
The study finds that the incidence of myocarditis is relatively uncommon in recipients of COVID-19 mRNA vaccines. However, young men are more likely to develop the disease than women.
As the scientists have mentioned, patients with a documented history of vaccine-induced myocarditis should be carefully screened for booster doses.
*Important Notice
medRxiv publishes preliminary scientific reports that are not peer reviewed and, therefore, should not be considered conclusive, guide clinical practice / health-related behavior, or treated as established information.
Source
[ad_2]
Source link