Study Finds Potential Cardiovascular Risks From COVID-19

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A study published online on July 27 in the JAMA Cardiology journal found that there could be ongoing cardiovascular risks for people that contract COVID-19, independent of pre-existing conditions, severity and overall course of the acute illness. There are a boatload of disclaimers to come later, but the general study findings underscore an important consideration for athletes that we need to make clear at the outset.

(Before getting to that consideration, a note: nothing in this article is to be read as medical or health advice. Listen to your doctor. Don’t be stupid.)

My wife Dr. Megan Roche is an epidemiology researcher and coach, and for our athletes returning from a COVID-19 infection (even one without severe symptoms), we have advised them that it is best to be extremely cautious and deliberate, always erring on the side of more rest and less intensity. COVID-19 could possibly have non-linear and somewhat unpredictable effects on the cardiovascular system (and possibly other systems), and given the uncertainty right now, rushing back could be extra risky.

For athletes recovering from COVID-19: when in doubt, chill out. That sentence rhymes so it’s basically ready for publication in a prestigious journal.

For athletes recovering from COVID-19: when in doubt, chill out. That sentence rhymes so it’s basically ready for publication in a prestigious journal.

There are no certain answers right now, though.

We are living a science fiction novel on a global scale, but we’re still in an early chapter, and medical knowledge is evolving rapidly. Please be careful. Extra time off will be fine long-term, and the athletic risks of coming back soon are unknown.

Study Overview

Here are the facts, with the caveats coming later. The study included 100 patients in Germany who had recovered from COVID-19, 47 female and 53 male, with a median age of 49. The patients were selected through a diagnosis registry. Of the patients, 67 recovered at home (18 of those asymptomatic) and 33 required hospitalization. Median time from diagnosis to evaluation was 71 days. There was an age-matched and sex-matched healthy control group of 50 individuals, plus a risk-factor-matched group of 57 more individuals. All participants underwent cardiac magnetic resonance imagining (CMR), plus blood tests. Measurements and comparisons were conducted blindly or by software.

The findings showed the following cardiovascular effects for the 100 recovered COVID-19 patients:

-78 patients had abnormal CMR findings

-High-sensitivity troponin T values were detectable in 71 patients, a value often indicative of heart-muscle impacts

-Patients had lower left and right ventricle ejection fraction, a measurement often used to determine heart function

-Patients had higher left ventricle volume and mass, sometimes used to indicate heart stress

-Patients had raised T1 and T2 measures, another possible indication of cardiac inflammation

-Many of the findings were cross-correlated for individual patients

The findings were “irrespective of preexisting conditions, the severity and overall course of the COVID-19 presentation, the time from the original diagnosis or the presence of cardiac symptoms.”

Our findings reveal that significant cardiac involvement occurs independently of the severity of original presentation and persists beyond the period of acute presentation …

Since the COVID-19 pandemic began, cardiac involvement has been seen in hospitalized patients during acute infection phases. Some doctors and epidemiologists have suspected continued involvement, including in non-serious cases. The study authors laid out the stakes with the new information: “Our findings reveal that significant cardiac involvement occurs independently of the severity of original presentation and persists beyond the period of acute presentation, with no significant trend toward reduction of imaging or serological findings during the recovery period.”

Now, let’s do the disclaimer dance.

Given the seriousness of the topic, the disclaimer dance will be a bit more somber than usual (like the famous TikTok video). While the cardiovascular findings are associated with pathophysiological processes and negative outcomes, that next step has not been confirmed by the study. It’s possible that CMR abnormalities associated with COVID-19 act differently as a proximate cause of morbidity and mortality.

The time courses of the CMR abnormalities are uncertain. Perhaps the measurements were taken on the tail-end of a healing process.

The study was only on 100 patients, and with millions infected, there could be population-wide variation that will only become clear with larger cohorts. The findings do not represent fully asymptomatic patients, as the sample size was not large enough. It’s possible that larger sample sizes will reveal correlations related to illness severity or other variables. Maybe age plays a role, or other demographic characteristics not captured by the study. Other studies may refute these findings later. Finally, the study was conducted in Germany, and a 2019 Washington Post article described the decades-long love affair Germans have with David Hasselhoff, so perhaps loving David Hasselhoff is a confounding variable.

For the purposes of this article specifically, the study did not apply to athletes or athletic performance. So any guesses that follow are pure speculation. The cardiovascular abnormalities should impact athletes, but perhaps athletes have some protective factors against the impacts measured. It’s tough to know, so we’re all swimming in a pool of uncertainty. If I start to go under, I’ve got dibs on being rescued by The Hoff.

Uncertainties for Athletes

There are numerous anecdotes about how COVID-19 may affect athletes, but given that population-wide results are not published, I don’t think it’s helpful to scare you with horror stories or soothe you with fairy tales. So I’ll provide a brief overview of what I have seen as a coach to show you how individually variable it can be.

One athlete recovered rapidly, back to full speed without almost any issues. Another athlete came back as they would from the flu and had a relapse of symptoms. Yet another athlete cannot hit paces from pre-infection four months later, while the final athlete I have coached with a confirmed infection had bad symptoms at first, but came back strongly.

Many anecdotal articles back up the variable responses. For example, Boston Red Sox star pitcher Eduardo Rodgriguez will not pitch this season after being diagnosed with COVID-19 in March and subsequently suffering from myocarditis, inflammation of the heart (similar to some of the patients in the study). Meanwhile, Rudy Gobert of the Utah Jazz, whose infection spurred the cancellation of the NBA season in March, was flying through the air for a thunderous dunk in the first game this weekend. And when it comes to long-term effects for endurance athletes whose cardiovascular systems are stressed differently, it’s anyone’s guess.

The variable response rate may not just be related to cardiovascular issues, but also related to other systems. There is some speculation that COVID-19 may affect stress hormone cortisol, as outlined in a June article in The Lancet. Effects could be related to the endocrine system (see this article from April). Lung damage is variable but can be severe, even in patients without severe symptoms (June article), and respiratory health could be affected (April article). Megan could list off a bunch more risks and disclaimers, but I don’t know if it’s helpful to you in making decisions for your athletic life. We just don’t know for sure.

Coming Back from COVID-19

In the face of that uncertainty, for athletes we coach, we strongly suggest coming back from suspected or confirmed COVID-19 infection with extreme caution. Listen to your doctor and all medical advice, and err on the side of safety beyond those recommendations if concerned. We are just starting to understand how COVID-19 affects the general population, and I imagine that findings for high-volume runners might be months or years away.

For our athletes, we have developed a general rule. After athletes are cleared to run by their doctor, we treat return-to-run after infection more like a stress fracture than the flu.

For our athletes, we have developed a general rule. After athletes are cleared to run by their doctor, we treat return-to-run after infection more like a stress fracture than the flu. With the flu, athletes can pay attention to symptoms and ramp up when they feel fully healthy. But with stress fractures, the risk of reinjury necessitates a slow return even when things feel good, starting with a big rest period before ramping up gradually. In addition, we caution our athletes against exertion above aerobic threshold or in extreme heat due to the potential cardiovascular stress.

COVID-19 sucks. For athletes, it could have impacts that aren’t immediately apparent from symptoms. Listen to your personal doctor and Dr. Fauci. When in doubt about your athletic decisions, be extra safe and ease back in even more than you might be tempted to, adjusting for new information (or information this article misses).

Even if you feel safe from the worst impacts of COVID-19, take it seriously. The virus seems to be playing by different rules. And we’re all still trying to figure out what game we’re playing.

David Roche partners with runners of all abilities through his coaching service, Some Work, All Play. With Megan Roche, M.D., he hosts a weekly, 30-minute podcast on running (and other things), and they wrote a book called The Happy Runner

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