With confusion around the world regarding how COVID-19 harms the heart, an Israeli cardiologist says he has pieced together the clearest picture to date.
The disease causes a unique pattern of damage on the right side of the heart, which occurs in two out of every five hospitalized patients, according to a team led by Dr. Yishay Szekely of the Tel Aviv Sourasky Medical Center.
“Nobody knew what actually happened to the heart, and we’re now saying that 40 percent of hospitalized patients suffer from dysfunction on the right side, and that it’s rarely harming the left,” Szekely told The Times of Israel.
“We’ve proved what actually happens in the heart, and this is the first step toward understanding the disease better in relation to the heart, and more effectively guiding future treatment,” he added. “I believe that this is a big step.”
Szekely recently published his research in the American Heart Association journal Circulation, and says that the 100-patient study is the world’s first to systematically use cardiac imaging to show the impact of coronavirus on the heart, rather than relying on laboratory tests alone.
COVID-19 is thought to manifest itself mostly as a respiratory illness, but is known to commonly cause heart damage. Szekley said that he instituted heart imaging for many of his hospital’s coronavirus patients in order to get some clarity — and has been surprised by what he saw.
He expected to witness damage to the left side of the heart, based on early reports from China and Europe, but instead found that almost all cases of heart damage are in the right ventricle.
When viruses cause direct damage to the heart, they mostly affect the left side, said Szekley. He added that there may also be harm to the right side, but he has never encountered a virus that consistently caused damage to the right side alone.
But as this seemed to be the case with COVID-19 based on his study, he said, there were only two ways of interpreting the results. One was to conclude that coronavirus has a different effect on the heart than other viruses — Szekely dismissed this as highly unlikely. The other possibility was to conclude that the heart isn’t reacting directly to the virus, but rather to strain in the lungs.
This made sense, Szekely said, given that the right side of the heart is tasked with pumping blood to the lungs. “Elevated pressure in the lungs causes the right side of the heart to work harder,” he said. “Think of a pump that needs to work harder because of more resistance.”
This finding should discourage researchers from investing in directly addressing the impact of coronavirus on the heart, and encourage them to consolidate their efforts on finding ways of improving patient health in the lungs, Szekely said.
He has several theories as to why the disease is damaging the right side of the heart, some related to the lungs’ reaction to the virus, and one hypothesis that suggests that treatment could actually be agitating the lungs.
“It may be that if you ventilate patients at high pressures you cause damage, so it could be caused by the treatment and not by the disease,” he said. If true, this would vindicate some doctors who have claimed that ventilation can sometimes be harmful.
Szekely thinks the main importance of his work is that insights into how the disease affects the heart will help researchers, doctors and drug companies to develop treatments. But he said that even before such breakthroughs, his findings can help doctors with patient care.
Based on the research and on his current hypotheses for explaining his findings, Szekely believes doctors may want to start paying close attention to the right side of the heart throughout hospitalization.
“The research can already start to help guide treatment, for example [by] prompting use of blood thinners in order to allow the right ventricle to work against lower pressure, and adjusting ventilation parameters based to a greater degree on the state of the patient’s heart,” he said.