Cardiac Testing Post COVID-19: Of Echos and MRIs

CVCT CardioBrief published online earlier this week a letter from a group of “clinicians, researchers and imaging specialists” who are concerned about the “presentation, interpretation and media coverage of the role of cardiac magnetic resonance imaging in the management of asymptomatic patients recovered from COVID-19.”

It’s short and sweet but makes many excellent points.

Let’s look at their major points (bulleted and red) one by one

  • Studies123 investigating the prevalence of myocarditis in patients with recent COVID-19 have found features of subclinical myocarditis on cardiac magnetic resonance (CMR) imaging in patients without symptoms.

Reference 1 is the German cardiac MRI study that first got me “worried” about cardiac consequences of COVID-19. It has gotten a lot of flack (spearheaded by posts on Twitter including those of Dr. Venk Murthy, the first author on this letter), has been revised and errors corrected. It still has me worried which brings us to point two of the letter:

  • Some commentators have raised concern that COVID-19 may lead to frequent, serious long-term cardiac sequelae even among people who have had mild infection and are currently asymptomatic.

This is definitely true, lots of prominent doctors have suggested this. Here’s what I (a not so prominent doctor) wrote:

Note that left ventricular ejection fraction (LVEF), the most common measure of the systolic or pumping function of the heart although lower in the COVID-19 patients was not depressed below normal values. This means these cardiac abnormalities would not be detected on more commonly available cardiac diagnostic methods like echocardiography.

Also note that risk-factor matched controls have a fair number of CMR abnormalities and that we don’t know what cardiac MRI would show in a comparison group of patients recovering from the flu.

Despite these limitations, “given reports of ongoing cardiac symptoms in many post-COVID-19” I agreed with an accompanying JAMA editorial,” entitled “Coronavirus Disease 2019 (COVID-19) and the Heart—Is Heart Failure the Next Chapter?” and written by two prominent heart failure researchers/clinicians and JAMA editors, Clyde Yancy and Gregg Fonarow, which concluded:

“We wish not to generate additional anxiety but rather to incite other investigators to carefully examine existing and prospectively collect new data in other populations to confirm or refute these findings. We hope these findings represent that of a select cohort of patients. Yet, if this high rate of risk is confirmed, the pathologic basis for progressive left ventricular dysfunction is validated, and especially if longitudinal assessment reveals new-onset heart failure in the recovery phase of COVID-19, then the crisis of COVID-19 will not abate but will instead shift to a new de novo incidence of heart failure and other chronic cardiovascular complication”

Both I and the prominent authors of the editorial I quote state a long list of caveats and other things that would need to be proven before knowing that COVID-19 creates long-term cardiac consequences. However, most non-scientist readers of media reports tend to filter out all the boring caveats (which we must face and incorporate continuously in clinical medicine) and focus on worst-case (or best case) scenarios.

  • We wish to emphasize that the prevalence, clinical significance and long-term implications of CMR surrogates of myocardial injury on morbidity and mortality are unknown.

Absolutely true.

  • Further, it is unclear if the elevated T1 and T2 flagged in these studies are clinically significant, particularly in isolation, if treatment is needed, and, if so, what the management should be.  These important questions should inspire future prospective studies.

Totally agree. I’m no expert on CMR but having utilized it in my cardiomyopathy patients, researched the literature and discussed with experts in the field I know that LGE (late gadolinium enhancement) is the most validated tool and has well established diagnostic and  prognostic data. It was the LGE data in the German CMR study I was most concerned about. As this table demonstrates (left column asymptomatic COVID-19, right column matched controls) the COVID-19 group had a five-fold higher prevalence of non ischemic LGE (and pericardial effusion.)

The letter concludes with a request that professional societies discourage CMR screenings;

Nonetheless, these reports have attracted significant media coverage, at times amplified by speculation on possible clinical implications, thus generating substantial anxiety amongst members of the general public. As a result, we are aware that some individuals are seeking CMR testing despite the absence of cardiac symptoms. We believe that, given the preliminary nature and limitations of the current evidence, testing asymptomatic members of the general public after COVID-19 is not indicated outside of carefully planned and approved research studies with appropriate control groups.

In light of your societies’ standing in the community and advocacy against low-yield testing and low-value medical care through your sponsorship of the Choosing Wisely, Image Wisely, and other similar campaigns, we request that you offer clear guidance discouraging CMR screening for COVID-19 related heart abnormalities in asymptomatic members of the general public.

It’s really hard to justify CMR testing on asymptomatic patients post COVID-19, hopefully physicians and patients will avoid ordering them in this situation.

Evaluation of Heart Failure Post COVID-19

But what about patients with signs or symptoms of heart failure that develop after COVID-19? Typically, heart failure symptoms consist of breathlessness, fatigue or leg swelling, symptoms which are also common following respiratory illnesses thus likely to be common after COVID-19 illness whether or not there is any cardiac pathology.

For now, my approach to such patients will be exactly like my approach to any other non-COVID-19 patient in whom symptoms could be due to heart failure. Following a detailed history and physical exam we will check and ECG and an echocardiogram. The echocardiogram is a wonderful tool for evaluating patients who may have congestive heart failure as it is totally noninvasive, ubiquitous (in the US), inexpensive (or should be) and painless.

A well-performed and well-interpreted echocardiogram gives information on the structure and pump function of the left ventricle (EF), pressures in the heart and pulmonary arteries, right ventricular function, valvular function and is the gold standard for determining presence or absence of pericardial effusion.

I’ll also check some basic lab tests on such patients including tests of kidney and liver function, blood counts, thyroid function, CRP and a BNP or pro BNP level.

I would not order CMR on these post COVID-19 heart failure patients unless abnormalities on one or more of the tests in conjunction with the history and physical convinced me the patient had evidence of myocarditis or cardiomyopathy.

We have lots to learn about COVID-19 and the heart. CMR evaluation of post-COVID-19 in the context of well thought-out research protocols can contribute to our understanding but CMR evaluation of asymptomatic COVID-19 patients would create unnecessary confusion, fear, and anxiety which would outweigh any clinical benefits.

Ultrasonically Yours,



9 thoughts on “Cardiac Testing Post COVID-19: Of Echos and MRIs”

  1. I am the parent of a college D1 swimmer who tested positive for Covid but remained asymptomatic. In order to return to the pool, he has had an EKG, and a Troponin level, both of which were considered normal. Then an echo was ordered. It came back with both enlarged ventricles and an enlarged right atria.
    Prior to this study, he was working out on his own, putting in some serious workouts, both in the pool and dry land—and feeling great with no symptoms. He has since only been told to stop doing workouts for the time being.

    We are awaiting the university’s response as to what happens next. But my question is, how do we know if the enlargement is due to his roughly six years of intense training and competitive activity or if this is indeed a Covid incident? Are there other tests that need to be considered?

    Thank you!!

    • Debra,
      I’m sorry to hear of your son’s COVID experience. These are tough questions you are asking that the entire athletic community is grappling with.
      ” how do we know if the enlargement is due to his roughly six years of intense training and competitive activity or if this is indeed a Covid incident? ”
      Enlargement of cardiac chambers is the norm for competitive athletes and without a baseline echo it is difficult to know if COVID has somehow contributed.
      Are there other tests that need to be considered?
      This is the issue I addressed in my post.Cardiac MRI could be performed in this situation. But as your son is free of any symptoms any abnormalities on the MRI could be false positives. And the experts writing the letter I reference do not recommend CMR in this setting.
      If I were seeing your son I would very carefully analyze the echocardiogram measurements, likely making my own repeat measurements to be certain and to get a feel for how significant the enlargement is and I would be looking for subtle abnormalities of cardiac dysfunction.
      If time permits I will write a post on these specific questions as no doubt lots of athletes are encountering the same problem.

      • Thank you so much for reply. Since I commented here a few days ago, a cardiologist who lists “sports cardiology” as an area of his practice is reviewing the cd from his echo. We hope to have more information soon. But at least in the interim, we have more peace of mind knowing that another expert will be weighing in. My son continues to feel great and is anxious to get back to work in the pool as soon as he is deemed to be healthy to do so!

        Thank you again!

  2. Really good article, appreciate the tone which is tempered with pragmatism and humility. As you pointed out, there is still a lot to learn about this virus and there are a lot of unanswered questions that will hopefully be answered by well controlled studies. Pertaining to your article in regards to frequency of cardiac damage in patients with other viruses, Anish Koka (a cardioMD on twitter) cited a study with an H1N1 infected cohort that had CMR done with abnormal findings in all 3 metrics of T1,2 and LGE. It does beg the question how many other viruses show cardio tropic characteristics with transient or permanent insults the CV system that we are unaware of. I also wonder if the COVID era will usher in a whole new era of research and investigation into chronic inflammatory diseases caused by viral infections. My understanding is that some viruses can cause cancer and inflammatory diseases like Epstein Barr, but I would love to see more data on common viruses like rhinoviruses as well as influenza to see in comparison if there are any residual effects on cardiomyocytes or suspected myocarditis. Controls are essential for this information to be relevant so I hope there are new studies planned so we can get more answers.

      • I figured you were, I was unaware until recently that there were other studies that showed abnormalities with other viruses like H1N1 which I thought was interesting. To go even further I was unaware of the german COVID CMR study until I saw it posted on your blog and what the ramifications were until you explained it to me via the comments. This is a whole new realm that I have yet to explore (virus impact on the CVS). It ties into two things I find very fascinating the immune system and the heart.

        With that said, did the H1N1 study influence your thoughts on the abnormalities seen in the german CMR study? From my point of view the H1N1 virus study was eye opening in that maybe cardiac abnormalities might be more common with many types of viruses than thought due to lack of CMR testing. It might also be that these abnormalities are only seen in certain individuals with certain qualities that are not yet elucidated. I have so many questions but I guess the main ones revolve around are the abnormalities long lasting and do they influence long term health outcomes.

        • The H1n1 study suggests thatCMR abnormalities are created with other viruses. Whether COVID-19 is a particularly bad actor for heart failure/myocarditis in comparison to other viruses remains to be proven.

  3. I am not clear. Does this mean that those that who get the virus and are largely free of symptoms can suffer some degree of damage to the heart without knowing it? If so, I would at this point assume that it could affect other organs as well.


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