Imaging tool could help identify COVID-19 patients at risk of heart issues, study says

TORONTO —
A new study suggests that a common imaging tool used to examine the heart may be helpful in evaluating COVID-19 patients at risk of developing heart issues that could increase the chance of heart failure or stroke.

Researchers at Johns Hopkins Medicine in Maryland took a retrospective look at around 80 COVID-19 patients and 34 patients without COVID-19, all of whom had received imaging tests called 2-D echocardiograms.

Echocardiograms use sound waves through a transducer placed on the patient’s chest to create images of the heart walls and valves, sort of similar to how a bat uses echolocation to see.

A 2-D echocardiogram captures the actual motion of the heart, in a cone-shaped “echo” that is displayed on a computer screen, allowing doctors to see the real-time motion of the structures of the heart.

These imaging tests allowed researchers to observe various parts of the heart throughout the patients’ illness, and connect different patterns with the outcomes each patient had.

Injury to the heart has been associated with more severe outcomes for COVID-19 patients, but a link between heart irregularities and COVID-19 patients who suffer heart injury has not been previously examined, the study stated.

The research was published in May in the Journal of the American Society of Echocardiography.

“These findings show that hospitalized COVID-19 patients have reduced [left atrium] function compared to COVID-19-negative controls with similar degree of critical illness,” the study stated.

The left atrium is where the heart receives oxygenated blood from the lungs. By measuring left atrium strain through the echocardiograms — ‘strain’ meaning a measurement of how much the left atrium is moving to do its job — researchers found the left atrium in COVID-19 patients was moving significantly less than the control patients, and could move less blood through it with each pump.

But the left atrium function was reduced even more in COVID-19 patients who also developed atrial fibrillation or flutter while in hospital with the virus, with these patients showing 30 per cent less function in their left atrium. Atrial fibrillation refers to an irregular heartbeat, frequently a rapid one, that occurs when the chambers of the heart are out of sync.

Researchers say that using echocardiography to keep an eye out for these issues could help identify them early on.

“A lot of patients already get echocardiograms while in the hospital; the addition of strain analysis requires no extra scanning of the patient,” Erin Goerlich, a cardiology fellow at the Johns Hopkins University School of Medicine and first author of the new paper, said in a press release. “So this is a safe and affordable new data point that can clue us in about who might develop atrial fibrillation.”

The blood of patients who developed atrial fibrillation also had some differences compared to other COVID-19 patients, containing higher levels of troponin and NT-proBNP, “two known markers of heart stress,” according to the release.

“This tells us that COVID-19 patients with high levels of these biomarkers should be followed more closely and may benefit from an echocardiogram,” Goerlich said.

The study suggested that “systemic inflammation in COVID-19” could be a contributing factor in this specific type of irregular heartbeats.

Although blood thinners are often used to treat those with atrial fibrillation, researchers noted that this strategy was not tested in this study, and that more research is necessary.

But pending future studies, it’s possible that “this could lead to new therapies to prevent strokes and heart attacks in certain COVID-19 patients who are at the highest risk,” Allison Hays, medical director of echocardiography programs at The Johns Hopkins Hospital and senior author of the published paper, said in the release.

“We’re also actively studying how these effects on the heart might persist after SARS-CoV-2 infection,” she added. “It’s important to know whether those measures of strain and emptying fraction improve over time.”