Japanese researchers said they found evidence of long-term heart damage in people who received COVID-19 vaccines — including in asymptomatic patients — even though vaccine-induced myocarditis was thought to be rare, transient and limited to subjects experiencing heart symptoms.
Regardless of age or sex, patients who received their second vaccination up to 180 days before imaging showed a 47% higher uptake in heart tissues of fluorine-18 fluorodeoxyglucose (FDG), an imaging agent, than unvaccinated subjects.
FDG is identical to glucose, a sugar that is the body’s main energy source, but it contains fluorine-18, a radioactive form of fluorine that allows imaging of organs and tissues where FDG accumulates.
Stressed or damaged cells, a hallmark of myocarditis, take up more glucose than healthy cells.
Researchers led by Takehiro Nakahara at Keio University School of Medicine used a retrospective study design to compare positron emission tomography/computed tomography (PET/CT) scans between patients undergoing imaging before COVID-19 vaccines were available (from Nov. 1, 2020, to Feb. 16, 2021) to scans on other subjects after the vaccine rollout (Feb. 17, 2021, to March 31, 2022).
The 1,003 subjects — 700 vaccinated against SARS-CoV-2 and 303 unvaccinated — were grouped by age (younger than 40, 41-60 years, and older than 60), sex and time between vaccination and PET/CT.
Of the vaccinated subjects, 78% received the Pfizer-BioNTech BNT162b2 product while 21% got the Moderna mRNA shot. No difference in FDG uptake was observed in patients taking either product.
Subjects who received AstraZeneca’s shot, or one of the other less common vaccines, were excluded because their low numbers would have introduced uncertainty to the analysis.
To capture safety signals from asymptomatic subjects only, investigators chose subjects who were scanned for issues unrelated to the heart. Most scans were for cancer diagnoses.
Higher FDG uptake was also observed in tissues outside the heart, including the liver, spleen, and the whole body, and particularly in axial (armpit) lymph nodes. Earlier studies claimed these effects disappear after 2-3 weeks, but Nakahara showed they last for up to six months.
Twenty-five subjects had more than one scan during one or both study periods, and 16 underwent a PET/CT test in both the pre- and post-vaccine time periods. Within this small subgroup, vaccinated subjects showed significantly higher FDG uptake in both the heart and axial lymph nodes.
Although myocarditis persisted longer than 120 days, its occurrence was not statistically significant beyond that time point.
Myocarditis occurs in the general population at rates of 6.1 and 4.4 per 100,000 for men and women, respectively. Symptoms include chest pain, shortness of breath and heart palpitations.
According to the Centers for Disease Control and Prevention (CDC), “Most patients with myocarditis or pericarditis after COVID-19 vaccination responded well to medicine and rest and felt better quickly.”
Treatment for myocarditis involves rest, pain relievers, anti-inflammatory medications and in some cases, hospitalization.
Nakahara and co-authors listed three limitations to their analysis.
First, since this was a retrospective study from a single hospital with limited ability to control for a subject’s health status and metabolism, its power to predict myocarditis was limited. This led the study authors to conclude: “A prospective study would be needed to validate the findings of this study, including comparisons with cardiac enzyme levels, cardiac function, and non-mRNA vaccination.”
Second, since scan results came from historical records, investigators were unable to prepare subjects appropriately for an FDG heart study. FDG accumulates and is metabolized similarly to table sugar, so subjects undergoing FDG imaging usually undergo a fast or specialized diet leading up to the test. Nakahara could not control for pre-scan prep.
Third, the FDG tests were not performed specifically to assess myocarditis.
In an editorial critique appearing in the same issue of the same journal, David Bluemke, M.D., Ph.D., a cardiovascular imaging specialist at the University of Wisconsin School of Medicine and Public Health, downplayed the Japanese researchers’ findings, noting two other deficiencies that may have skewed results upward.
Bluemke described Nakahara’s subject inclusion criteria as providing a “convenience sample” — one that was tailor-made for a desired result. He argued that the higher cardiac uptake of FDG might be normal for cancer patients and not a result of vaccination.
But his main criticism focused on the limitations of FDG heart scans. “Unfortunately, in routine clinical practice, 18F FDG PET/CT is a terrible tracer with which to evaluate myocardial inflammation … because glucose is the normal source of energy for the myocardium [heart],” Bluemke wrote. “Routine PET/CT cannot help to reliably identify higher activity due to inflammation on an already high background of normal myocardium.”
‘Almost no one who took a shot right now has a normal heart’
Not all commenters were skeptical, however.
Dr. Peter McCullough, a cardiologist and critic of COVID-19 vaccination, commented on the Nakahara study in an online interview with Zeee Media.
McCullough noted the record numbers of cardiac arrests in young people, including athletes. Despite normal autopsy findings in most of those cases, “Something is wrong with the heart,” he said.
McCullough told Zeee Media:
“This late-breaking paper by Nakahara and colleagues filled in a lot of the answers. Positron emission tomography is a test that I order when I’m looking for a diseased area of the heart. Typically the PET scan will be positive in a zone that’s not getting enough blood flow or is diseased.”
McCullough explained that the human heart requires free fatty acids as its fuel source. Heart muscle cells that change to preferring glucose signal metabolic dysfunction or disease.
“What Nakahara reported was that for nearly every person who took a COVID-19 vaccine, the heart began to prefer glucose over free fatty acids,” McCullough said. And FDG lit their hearts up “like a Christmas tree. But people who didn’t take the vaccine had normal PET scans. Nakahara had patients out to six months after the shots and the changes were [still] there.”
When asked if the damage was permanent, McCullough said, “We don’t know. We don’t know the implications — they’re so broadly reaching — but what I can tell you today, it looks like almost no one who took a shot right now has a normal heart by positive emission tomography scan.”
McCullough cited a study that found heart damage nine months post-vax, and other work suggesting that the risk of permanent heart damage was about 2.5% per shot, meaning someone who took two shots plus a booster may have a nearly 8% increased risk for persistent myocarditis compared with unvaccinated individuals.
McCullough’s clinical experience is in line with these findings. He reported seeing some small areas of damage in the left ventricle, the heart’s main pumping chamber, resolve over time, typically after more than a year of treatment, but involvements above 15% do not resolve.
“In general, when there’s more than 15% of the left ventricle involved with myocarditis the risk of cardiac arrest skyrockets.”
Bluemeke based his commentary on the assumption that the U.S. Vaccine Adverse Event Reporting System (VAERS) accurately captures all vaccine-related injuries.
He wrote that by December 2021, VAERS “contained 1626 reported cases of myocarditis that occurred within 7 days of vaccination,” which translated to a myocarditis rate of between 7 and 11 cases for every 100,000 mRNA vaccine doses administered.
Bluemke noted that this rate was later revised to between 8-27 cases per 100,000 males, and a March 2021 study confirms this re-estimate.
But VAERS’ ability to record all or even most vaccine side effects has come under question. A November 2023 editorial in the British Medical Journal noted that:
“VAERS is supposed to be user friendly, responsive, and transparent. However, investigations by The BMJ have uncovered that it’s not meeting its own standards. Not only have staffing levels failed to keep pace with the unprecedented number of reports since the rollout of covid vaccines but there are signs that the system is overwhelmed, reports aren’t being followed up, and signals are being missed.”
A late-2020 study submitted in July and presumably written before or at the beginning of the pandemic reported that VAERS’ capture of anaphylaxis — a severe, life-threatening immune reaction — following vaccine administration was routinely in the 12-24% range. In other words, as many as 7 in 8 cases go unreported.
An October 2021 preprint analysis by Spiro Pantazatos, Ph.D., a neuroscientist then at Columbia University, “suggests VAERS deaths are underreported by a factor of 20, consistent with known VAERS under-ascertainment bias.” Pantazatos concluded that “the risks of COVID vaccines and boosters outweigh the benefits in children, young adults and older adults with low occupational risk or previous coronavirus exposure.”
Pantazatos’ status as a Columbia faculty or staff member is unclear, as is the publication status of his paper. Columbia still lists him on neuroscience web pages but an email to his columbia.edu address bounced. Pantazatos most recently was associated with the Brownstone Institute, which still lists his main affiliation as a Columbia assistant professor.
As late as Sept. 12, 2023, the CDC reported that anaphylaxis rates following COVID-19 vaccination occurred in just 5 of 1 million administered doses — a rate 50 times lower than the number Bluemeke cited in his editorial.
According to the latest VAERS data, 26,366 cases of myocarditis/pericarditis were reported following COVID-19 vaccination between Dec. 14, 2020, and Oct. 27, 2023. There were also 5,385 reports of myocardial infarction.
