By Bana Jobe
Of all the poor patient outcomes tied to the novel coronavirus—including ICU stays, severe COVID-19, and death—about half have one factor in common: the patient experienced a cardiac arrhythmia.
In a systematic literature review from the Indian Pacing and Electrophysiology Journal, researchers found an arrhythmia incidence rate of 48% among patients with poor outcomes compared to 6% among those without poor outcomes. According to a review in JACC: Clinical Electrophysiology, many of these have been Afib, but additional abnormalities seen in COVID-19 patients include atrial flutter, ventricular arrhythmias, and supraventricular tachycardias.
The stark contrast between the outcomes of COVID-19 patients with and without arrhythmias comports with research in Heart Rhythm that asserts these arrhythmias are likely the result of systemic illness, rather than COVID-19 alone. Notably, COVID-19 patients with underlying heart conditions face a 10.5% mortality rate, which is nearly twice that of COVID-19 patients with cancer.
These variances underscore the importance of diligence in cardiac monitoring among all hospitalized COVID-19 patients—not only to account for precipitating factors and the possibility of new myocardial damage from the virus, but also to guard against the potentially dangerous effects of QT-prolonging medications used to treat it.
Fortunately, ECG is a ubiquitous tool that can help clinicians establish baselines, track progress, identify risks, and inform care planning in real time.
The Relationship between SARS-CoV-2 and Arrhythmia
Recently, the Postgraduate Medical Journal listed the many precipitating factors of arrhythmias (Table 1). This table reveals a stunning pattern: many of the factors listed are issues directly associated with SARS-CoV-2 and may be tied to newly onset damage to the heart muscle or worsening preexisting cardiac conditions, including:
- Hypoxia from pneumonia
- Acute cardiac injury from acute respiratory distress syndrome, pulmonary embolism, or myocardial infarction
- Heart failure
Given the causal and corollary relationships between these precipitating factors and COVID-19, it's no surprise that arrhythmia has been found by JAMA to be the most common cardiac complication caused by the viral disease.
The Impact of COVID-19 Treatments on Heart Rhythm
The incidence of abnormal heart rhythms among COVID-19 patients appears to increase with the delivery of antivirals, antibiotics, and other medications. Many people now know of the QR-prolonging risks inherent in hydroxychloroquine, but other therapies may also pose arrhythmia risk.
One such medication is the antiviral lopinavir/ritonavir. As a study in the British Journal of Clinical Pharmacology reports, in vitro studies indicate that QT-interval effects may be caused by the antiviral agent, with theoretical models showing a potential prolongation of 5 ms or more. However, those results have not translated to in vivo findings, which has led healthcare organizations to require QTc assessment even in the absence of prolonged repolarization.
To learn more about the power of the ECG in today's clinical landscape, browse our Diagnostic ECG Clinical Insights Center.
The Role of the ECG in COVID-19 Care
The relationship between COVID-19 and cardiac arrhythmias has triggered a recommendation that is included in the Postgraduate Medical Journal paper: everyone who comes into the hospital with COVID-19 should have their QTc baselines recorded with an ECG.
In a decision-tree resource from that same paper, the authors provide this algorithmic guidance:
- An initial QTc that exceeds 500 ms may indicate that the patient faces a greater risk of poor outcomes and requires support from a cardiology team. The patient will need continual surveillance daily or even more frequently—even after being transferred from the ICU—and they should avoid QT-prolonging drugs. This monitoring should happen in tandem with other interventions intended to manage modifiable risk factors, including diuretic interventions and electrolyte restoration.
- An initial QTc that is less than 500 ms may indicate less risk. These patients may be able to begin treatment, even if the drugs being used are known to prolong QT. A daily ECG is still recommended, particularly for patients taking QT-prolonging medications. Any subsequent QT reading that is above 500 ms or which represents an increase of more than 60 ms will stratify patients into the first group of high-risk patients.
Operators should be familiar with how all waveforms can indicate high risk of arrhythmia—particularly abnormal P waves, which may help inform diagnoses of Afib or atrial flutter, as well as other rhythm problems.
Never Forget the ECG
As a low-cost, portable option, ECG is always there to support care planning and arrhythmia risk stratification. Keep in mind, though, that it's just one of the tools available, and in these times taking an ECG can carry the additional risk of infecting technicians or clinicians.
Still, if healthcare professionals follow practice guidelines, routine use of a 12-lead ECG can help improve patient outcomes. In the words of the Postgraduate Medical Journal researchers, "never forget the ECG."
Bana Jobe is an award-winning freelance medical writer with more than ten years of content experience writing for hospitals, pharma, medical devices, digital health brands, payers, and more.
The opinions, beliefs and viewpoints expressed in this article are solely those of the author and do not necessarily reflect the opinions, beliefs and viewpoints of GE Healthcare. The author is a paid consultant for GE Healthcare and was compensated for creation of this article.