A study by the Oregon Health Authority finds reassuring findings that myocarditis, a complication of the COVID-19 vaccine, was not associated with cardiac death in previously healthy young people within 19 months of the first vaccine rollout. Evidence found.

However, due to its limitations, the study could not rule out the possibility that cardiac death could occur as a complication of the vaccine in very rare cases.

The study was published this week in the Centers for Disease Control and Prevention’s public health journal Morbidity and Mortality Weekly Report.

Myocarditis, which is essentially inflammation of the heart muscle, is a known but rare complication of the coronavirus vaccine. It most often occurs in adolescents and young men within 7 days of receiving their second dose of the mRNA COVID-19 vaccine.

The OHA study looked at deaths in Oregon after the initial rollout of COVID-19 vaccines from June 1, 2021 to December 31, 2022.

The authors used Oregon’s death certificate database to search for people between the ages of 16 and 30 who died from heart disease or an unknown cause during that time.

The results showed that there were a total of 1,292 deaths in the same age group. Of these, none had COVID-19 vaccination listed as a cause of death on their death certificates.

The authors then narrowed their focus to 66 men and 35 women who died of cardiac events or unknown causes, according to their death certificates.

Researchers used state vaccination records to determine whether any young people died within 100 days of receiving an mRNA COVID-19 vaccine. Three deaths were found that met that criteria.

One man died 21 days after receiving the coronavirus vaccine. His cause of death was given as congestive heart failure due to high blood pressure and other chronic illnesses. The second man died of “unexplained natural causes” 45 days after receiving the vaccine. One woman died of unknown causes four days after receiving the COVID-19 vaccine. Her death certificate listed chronic respiratory failure as a contributing factor.

Lars Gross-Waltman, a pediatric cardiologist at Oregon Health & Science University and an expert on COVID-19 vaccine myocarditis, was not involved in the study.

He said combining large datasets like this study is a helpful approach to better understand rare vaccine complications like myocarditis.

“For me, this study is reassuring in that we didn’t find any major conclusive evidence,” Gross-Waltman said. “They didn’t suddenly identify a dozen or so patients who had a close chronological association with the vaccine.”

“On the other hand, it’s not large enough or detailed enough to say, ‘This study suggests that there is no risk of sudden cardiac death,'” he added.

Without detailed medical records for the three patients identified in the study as having died within 100 days of vaccination, it would have been difficult to draw firm conclusions about these cases.

The woman’s death was likely vaccine-related, especially given the timeline of events, Gross-Waltman said.

“I don’t think we know,” he said. “While the paper’s conclusions are correct and the data do not support an association, it does not resolve the question of whether sudden cardiac death can occur.”

At the request of the Federal Drug Administration, Professor Gross-Waltman has led efforts to compile research and better characterize myocarditis after mRNA vaccination.

This effort found that the prognosis for young patients with myocarditis associated with mRNA COVID-19 vaccines was generally favorable. People who develop myocarditis after vaccination usually have mild symptoms and tend to recover quickly.

However, Gross-Waltmann said some patients have shown signs of heart damage or scarring on imaging scans, which seems somewhat at odds with the mild clinical symptoms of those cases.

Since the first case was reported in 2021, the longest period of follow-up of patients is three years.

“This has been long enough to say that these patients are doing well clinically, but it remains to be determined whether the trauma inflicted on some patients has any implications for their long-term health and survival. “It will be too short,” Professor Gross-Waltman said. .

Gross-Waltmann said the risks of rare vaccine side effects must be weighed against the benefits of vaccination. In the case of COVID-19 vaccination, potential benefits include reduced mortality, longer ICU and hospitalization stays, longer COVID-19 infections, and longer COVID-19 infections. Includes protection from cardiovascular risk factors.

The authors of the OHA study also looked at COVID-19 deaths among youth and young adults during the same period in 2021 and 2022. COVID-19 was cited as the cause of death for 30 Oregon residents in the same age group. Almost all had not been vaccinated.

“Although it is clear that the risk of cardiac death associated with COVID-19 vaccination is very low, if any, the risk of death from COVID-19 is real,” the study said. said author Paul Cieslak. “We continue to recommend COVID-19 vaccination for everyone six months of age and older.”