Kids who develop the rare post-COVID-19 complication known as multisystem inflammatory syndrome in children, or MIS-C, are at high risk for heart problems that could make it more difficult for the heart to pump blood efficiently for weeks after they are thought to have recovered, a new study from doctors at Children’s Hospital of Michigan found.
About 20% of children who developed MIS-C had heart function changes that could be detected with an echochardiogram, which is an ultrasound of the heart, and an electrocardiogram 10 weeks after they recovered, said Dr. Gautam Singh, chief of pediatric cardiology at Children’s Hospital of Michigan and the lead author of the study. A smaller subset of them continued to have heart dysfunction, mostly asymptomatic, for up to five months after they were hospitalized.
“With treatment, most of them have recovered and have done well,” said Singh, who also is a professor of pediatrics at Central Michigan University; he noted, however, that because COVID-19 and MIS-C are so new, ongoing study is needed to get a more complete picture of potentially long-term complications.
The observational pre-print study, published online in May in the Journal of the American Society of Echocardiography, examined 54 children who were admitted to the Detroit hospital between March 2020 and January and treated for MIS-C, which causes multiple organs, including heart and blood vessels, to become inflamed. It can lead to organ failure and damage.
“We found that acutely, most of them had involvement of the heart,” Singh said. “The function was either affected or valves became leaky or inflamed or there was buildup of some fluid around the heart, compromising heart function. And some were so much in shock that they required life support. Almost invariably, half of them required going on mechanical ventilation or a breathing machine, heart-supporting medications … and many other supports to their systems for them to survive and do well.
“Fortunately, they all did very well, and they went home, which is great gratification. When we studied these children and followed them about five to six months (later), we found about 19% to 20% have some involvement of their heart function that was not clinically obvious, but by echocardiographic measurements.”
It means, he said, that children who have had MIS-C shouldn’t resume sports or athletic activity without getting cleared by a pediatric cardiologist first, which is in line with guidance from the U.S. Centers for Disease Control and Prevention.
“That is because the heart is involved, and any time heart muscles become inflamed, you don’t want to exert or participate in … sports or strenuous physical activities within the first three to six months … after there was inflammation of the heart muscles,” Singh said. “You want the heart to recover completely; otherwise, if you participate in strenuous physical activities, it may damage your heart.”
In addition, he said, the study suggests echocardiograms could be used to identify which children should be treated most aggressively to prevent cardiac damage when they are admitted to the hospital with MIS-C.
“Since COVID-19 is a novel or new infection, we were not certain to start with when these children presented with MIS-C … how aggressively and with what medications to treat them.”
The research showed that children who had profoundly decreased heart function when they were admitted to the hospital with MIS-C were more likely to end up in the intensive care unit and need ventilator support to survive. But if medication to modulate their immune systems was given to them early, they had better outcomes, Singh said.
Since the pandemic began, there have been 123 confirmed cases of MIS-C in Michigan and five or fewer deaths. Nationally, the CDC reports that 3,742 children have had MIS-C and 35 have died from it.
About 70% of the children in Michigan who have been diagnosed with MIS-C were sick enough to require hospitalization in an intensive care unit, according to state data. Some of them needed heart-lung bypass machines, known as extracorporeal membrane oxygenation, or ECMO, to survive.
Most children who contract COVID-19 will not get severely ill, be hospitalized or die. It is unclear, Singh said, why some kids develop MIS-C and others do not.
“We don’t have the exact etiology about it, but there are certain common factors — what we call association, not cause and effect — that we have noticed,” Singh said. “Lots of these children have comorbidities like asthma, obesity. Unfortunately, the majority of these children were African American, which reflects the population of Detroit as well. But none of them had any cardiac problem, actually, prior to their MIS-C or prior to the exposure to COVID-19.”
Symptoms of MIS-C can appear four to six weeks after a child had COVID-19 or exposure to someone with the virus, and include:
- Abdominal (gut) pain
- Neck pain
- Bloodshot eyes
- Feeling extra tired
Singh said children 12 and older, who are now eligible for COVID-19 vaccines, should get the shots to prevent not only COVID-19 and potential long-term complications from the virus, but MIS-C as well. And if vaccines are approved for younger kids later this year, they, too, should be inoculated, he said.
“Once you see a child having and suffering from MIS-C you will not hesitate to recommend a vaccine,” Singh said.
Contact Kristen Jordan Shamus: email@example.com. Follow her on Twitter @kristenshamus.