COVID-19 "long-haulers"

During my GIM clinic today, I saw a new patient referred to us for intermittent palpitations in the context of a recent COVID infection. This patient was relatively young (in her mid-30's) and had developed symptoms of COVID about 3 weeks ago. Since her positive COVID test 2 weeks ago, many of her symptoms gradually self-resolved and it appeared that the worst of it was over. However, like many other patients across the world now referred to as COVID-19 "long-haulers," she has continued to experience lingering illness following recovery from her initial COVID infection. In addition to chronic fatigue and shortness of breath on minimal exertion, this patient has also been experiencing increases in her baseline heart rate as well as intermittent episodes of palpitations. 

What is being colloquially called "long COVID," also known as post-acute COVID, is beginning to emerge as a prevalent syndrome. Upon further research, I learned that common symptoms to persist after the initial acute infection include fatigue, breathlessness, chest discomfort, tachycardia, palpitations, and orthostatic intolerance, all of which can linger for up to weeks or months following the initial illness. Many studies have documented orthostatic intolerance syndromes in COVID long-haulers, including orthostatic hypotension, vasovagal syncope, and postural orthostatic tachycardia syndrome (POTS). It has been hypothesized that these specific symptoms may be related to an immune-mediated or virus-mediated disruption to the body's autonomic nervous system. Past studies have shown that autonomic disorders such as POTS are associated with antibodies. It is therefore logical to hypothesize that there may be an underlying autoimmune component to the orthostatic intolerance symptoms and autonomic dysfunction we are seeing in post-acute COVID.

Despite the lack of a definitive cure for these symptoms, there are many things we can do for these patients:

• Education: Arguably the most important component is explaining the underlying cause of these symptoms to patients and helping them manage the anxiety behind the uncertainty associated with COVID-19. In the case of my patient today, we referred her to the CANCOV clinic for more information and long-term follow-up for her post-COVID symptoms.
• Avoid exacerbating factors: It is important to counsel patients around taking more precautions like rising slowly from lying or seated positions and avoiding exacerbating factors like prolonged standing and dehydration.
• Appropriate exercise: It is advisable to initiate a regular exercise routine, incorporating both aerobic and resistance elements while avoiding further exacerbations to orthostatic intolerance (e.g. only engaging in exercises like swimming or cycling on a recumbent exercise bike).
• Isometric exercises: Patients can be educated on exercises that can increase venous return to the heart and raise blood pressure (e.g. tensing thigh muscles, crossing arms and legs, squatting, folding arms and leaning forward).
• Fluid and salt repletion: Given the orthostatic intolerance, it is important to ensure fluid repletion and adequate salt supplementation to maintain plasma volume and prevent hypovolemia.

I thought this case was a great learning experience since post-acute COVID is something that many junior learners know quite little about, but will likely become more and more prevalent in various clinical settings moving forward. Clinicians must be well informed of the possible symptoms and management techniques in order to help manage patients' symptoms while also avoiding unnecessary over-investigations.

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References:

Dani M, Dirksen A, Taraborrelli P, Torocastro M, Panagopoulos D, Sutton R, Lim PB. Autonomic dysfunction in ‘long COVID’: rationale, physiology and management strategies. Clinical Medicine. 2021 Jan;21(1):e63.