An Interview With Dr. Srihari S. Naidu (Part 1 of the COVID-19 Interview Series)

Quick Takes

"The first lesson really is that we cannot use our known experience and expertise on an unknown disease. We need to understand that what we've been doing for years may not always make sense."

Editor's Note: Cardiologists across the United States have experienced a variety of COVID-19 presentations and cardiovascular complications. The variety of these events reflects the continuous learning of health care professionals as we have come to better understand the extensive complexity of this disease. Recognizing the unique contributions of many, this digital interview format was created to compare the varied experiences our colleagues have seen and their reflections on this complex disease. We thank all of our contributors.

George W. Vetrovec, MD, MACC: First, what type of cardiac symptoms have you seen, and how frequently have patients demonstrated them? Reports suggest that primary respiratory failure is the predominant finding with associated fever, cough, and other "flu-like" symptoms but note that COVID-19 has a broad spectrum of presentations. Is this true, or do you have a different perspective?

Srihari S. Naidu, MD, FACC: From a cardiac standpoint, this disease appears to have a variety of secondary cardiac manifestations. As pulmonary disease progresses to acute respiratory distress syndrome (ARDS), with or without superimposed pneumonia, the cardiac output and index drop and often take these patients into Society for Cardiovascular Angiography and Interventions (SCAI) Shock Stage B or C. More severe Shock D and E appear to occur due to massive right ventricular (RV) dilation and failure, either from severe pulmonary failure with elevated pulmonary vascular resistance or due to concomitant pulmonary embolism (PE). Indeed, hypercoagulability has been a feature in later disease and can result in PE in a significant portion of patients. Treatment decisions in these patients are difficult, including use of anticoagulants or thrombolytics and when to escalate to veno-venous (VV) extracorporeal membrane oxygenation (ECMO). Of note, the majority of patients who require VV ECMO has not done well in case series, leading many to utilize it only in salvageable patients. Several cardiac disease states have been noted: myocarditis, coronary vasospasm, takotsubo cardiomyopathy, and ST-segment elevation myocardial infarction (STEMI) or non-STEMI. Troponin elevations are seen in a large subset of patients, up to 20%, and clearly portend a worse prognosis. Patients with true STEMI due to coronary occlusion have significantly greater peak troponin elevation, but true STEMI can be very hard to differentiate by electrocardiogram (ECG) from the other etiologies already mentioned. A STEMI ECG with reciprocal changes is more likely due to true coronary occlusion, but no reciprocal changes may indicate the other etiologies. This being said, patients who progress to any level of left ventricular (LV) dysfunction, either globally due to myocarditis or takotsubo or focal due to STEMI, appear to have a very poor prognosis and may represent a late stage of the disease.

Dr. Vetrovec: Also, there have been very few recognized heart attacks with a variety of myocardial injuries associated with COVID-19.1 Is this your experience? How have you distinguished STEMIs from COVID-19 myocardial injury?

Dr. Naidu: As I said, there are a variety of potential causes of ST-segment elevation on the ECG, some with reciprocal changes and others without. To date, differentiation has been by use of a rapid echocardiogram to look for diffuse and global versus more regional wall motion abnormalities. Diffuse or global dysfunction, RV failure out of proportion to LV failure, or classic takotsubo findings, especially in younger individuals, appear to more likely be a mimicker of STEMI, whereas focal, regional wall motion abnormality, preserved RV function, and reciprocal changes on ECG indicate more likely a true coronary occlusion. If the patient is salvageable, catheterization for possible primary percutaneous coronary intervention (PCI) appears to be prudent and is supported by American College of Cardiology (ACC) and SCAI consensus documents.

Dr. Vetrovec: STEMIs are down for patients without COVID-19, as published. Do you think out-of-hospital deaths have increased, suggesting that people have avoided coming to hospitals with dire consequences?

Dr. Naidu: Yes, I absolutely believe that patients with unstable coronary syndromes have not been presenting to the hospital for a variety of reasons. For one thing, there is fear of contracting COVID-19. Some of these patients unfortunately probably died at home of STEMI-related ventricular tachycardia/fibrillation or heart failure. Other patients probably also did not present because all cardiology offices have been closed. In New York City, the city's fire department published an article indicating that patients found dead at home increased fourfold.2 Although these increased deaths are multifactorial, it is likely some are related to delayed care of acute cardiac issues. Going forward, we must do a better job of minimizing fear and anxiety about coming to the hospital for non-COVID-19 illness, perhaps creating some hospitals that are "clean" with low risk of contracting COVID-19 or other diseases, such that patients feel safe. And we also have to do a much better job of transitioning to telemedicine and continuing our office practices to catch these patients in their homes.

Dr. Vetrovec: Although COVID-19 is a primary respiratory disease, 20% of patients develop severe cardiac symptoms, with hypotension reported frequently. Have you or your colleagues had experience with intra-aortic balloon pump, ECMO, or percutaneous ventricular assist devices in this setting? Why or why not?

Dr. Naidu: At our institution, we have placed almost a dozen patients on VV or veno-arterial (VA) ECMO. These patients are often very sick with profoundly low cardiac output due initially to RV failure, progressing in some cases to LV failure but in most cases to significant hypoxemia that can be difficult to ventilate. Indeed, various management strategies including high positive end-expiratory pressure, low tidal volumes, or the opposite, have been instituted, and many patients have also had to undergo proning to improve hypoxemia.

Dr. Vetrovec: You must have a huge backlog of patients whose "elective" procedures have been postponed. Have you seen adverse events in the patients in-waiting? Do you plan to triage patients by order of restarting testing and procedures? If so, how?

Dr. Naidu: We have kept track of the elective patients that we postponed and made sure to remain in contact with them. We also gave them instructions on symptoms to report that might require expediting their procedure. We have been continuing urgent and of course emergent procedures, but truly elective procedures we have handled by postponing for several weeks. The ACC consensus statement3 has given guidance on the types of procedures that would be considered urgent as opposed to elective, and this has been a good framework. With this management and communication, we have not had any adverse events in the patients who have been waiting. As we open back up, we will of course start with the patients who had been waiting, while still prioritizing patients who are urgent. One major challenge has been that although the emergency department, general floors, and procedural volumes have diminished, the intensive care unit (ICU) bed census has remained only slightly lower than the peak. This is because patients tend to remain on the ventilator for 2-3 weeks, which creates a lag time. This creates a bed capacity issue in the ICU that prevents us from opening up the procedural areas fully. In particular, patients who might need coronary artery bypass grafting and those who need ICU care, such as high-risk transcatheter aortic valve replacement, alcohol septal ablations, and some complex arrhythmias, will be limited by bed availability for the next 1-2 months. So, although lower-risk elective procedures including same-day PCI can open up quickly, patients with more complex disease that might need heart surgery or post-procedure ICU-level care will not be able to be performed at normal volumes for some time.

Dr. Vetrovec: Finally, what are your overall insights? What observations would you like to make? Perhaps a comment on self-protection and personal risk for the medical professionals. What else should we know?

Dr. Naidu: I think going forward, there are several lessons learned from the COVID-19 experience. The first lesson really is that we cannot use our known experience and expertise on an unknown disease. We need to understand that what we've been doing for years may not always make sense. The classic example here would be the STEMI findings that, in a normal population, indicate transmural infarction in the subtended territory but in COVID-19 may simply mean cytokine-storm with potentially no actual myocardial damage. Treatment would be completely different. We need to remain humble in the face of a new disease. The second lesson is that the health and safety of us as health care workers has to take priority over any individual patient, or else we will be in no shape to take care of subsequent patients. The example here we all know is that they always tell you to put your oxygen mask on yourself first before your child in an airplane emergency; that makes sense, of course. We must follow that lead and prioritize our own health and protection. A third lesson is that we did not anticipate that we would inadvertently ignore our non-COVID-19 patients, who ultimately suffered high death rates out of fear of coming to the hospital and out of poor access to their doctors. Telemedicine was never embraced by payors or doctors, and we now know that it will be vital going forward, both to keep track of our patients and to continue their necessary care. Life, and cardiac care, must go on even as we fight a separate pandemic. And finally, a good lesson here is that doctors need to retain some level of leadership and control in their hospitals in conjunction with business administrators. When the greatest challenges to hospitals are financial, as it has been for decades recently, administrators of course have the most insight. But when a pandemic comes on the scene, only doctors can truly understand how to combat it, and the best hospitals have to find a way to share that leadership and do it rapidly. Going forward, such dyad leadership paradigms should become the optimal strategy for hospitals and health systems.

Dr. Vetrovec: Thanks so much. I really appreciate your time and insight. Know we are all in this together, and we respect all you and your colleagues have gone through and continue to experience.

References

  1. Bangalore S, Sharma A, Slotwiner A, et al. ST-Segment Elevation in Patients With Covid-19 - A Case Series. N Engl J Med 2020;Apr 17:[Epub ahead of print].
  2. Tamman M. At-home COVID-19 deaths may be significantly undercounted in New York City (REUTERS website). April 7, 2020. Available at https://www.reuters.com/article/us-health-coronavirus-fdny/at-home-covid-19-deaths-may-be-significantly-undercounted-in-new-york-city-idUSKBN21P3KF. Accessed April 30, 2020.
  3. Welt FGP, Shah PB, Aronow HD, et al. Catheterization Laboratory Considerations During the Coronavirus (COVID-19) Pandemic: From the ACC's Interventional Council and SCAI. J Am Coll Cardiol 2020;75:2372-5.

Clinical Topics: Anticoagulation Management, Cardiac Surgery, Heart Failure and Cardiomyopathies, Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Stable Ischemic Heart Disease, Aortic Surgery, Cardiac Surgery and Heart Failure, Cardiac Surgery and SIHD, Mechanical Circulatory Support, Interventions and Imaging, Angiography, Nuclear Imaging, Chronic Angina

Keywords: COVID-19, Coronavirus, Coronavirus Infections, severe acute respiratory syndrome coronavirus 2, Coronary Angiography, ST Elevation Myocardial Infarction, Heart-Assist Devices, Respiratory Distress Syndrome, Adult, Extracorporeal Membrane Oxygenation, Percutaneous Coronary Intervention, Coronary Occlusion, Takotsubo Cardiomyopathy, Troponin, Tidal Volume, Cardiac Output, Low, Anticoagulants, Coronary Vasospasm, Myocarditis, Transcatheter Aortic Valve Replacement


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