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Published on: March 21, 2013
Attenuated cardiac autonomic function in patients with long-COVID with impaired orthostatic hemodynamics
Rashmin Hira1, Jacquie R Baker1, Tanya Siddiqui1
1Department of Cardiac Sciences, Libin Cardiovascular Institute, University of Calgary, GAC70 HRIC Building, 3280 Hospital Dr NW, Calgary, AB, T2N 4Z6, Canada.
Insights
Long-coronavirus disease (long-COVID) impairs autonomic function, with distinct abnormalities in initial orthostatic hypotension and postural orthostatic tachycardia syndrome. These findings highlight varied long-COVID pathophysiology, requiring tailored treatments.
Area of Science:
- Cardiology
- Neurology
- Physiology
Background:
- Long-coronavirus disease (long-COVID) is frequently associated with autonomic dysfunction, including orthostatic hypotension and postural orthostatic tachycardia syndrome.
- The underlying autonomic tone alterations in long-COVID patients with these hemodynamic phenotypes remain incompletely understood.
Purpose of the Study:
- To compare autonomic function between patients with long-COVID and healthy controls.
- To investigate autonomic differences within long-COVID subgroups presenting with distinct orthostatic hemodynamic profiles.
Main Methods:
- Beat-to-beat hemodynamics were assessed during a 10-minute active stand in 94 long-COVID patients (categorized by orthostatic hypotension, postural orthostatic tachycardia syndrome, or no abnormalities) and 33 healthy controls.
- Calculated measures of cardiovascular autonomic health included heart rate variability, blood pressure variability, and baroreflex sensitivity.
- Statistical analysis involved Mann-Whitney U and Kruskal-Wallis tests with Dunn's corrections for continuous data.
Main Results:
- Long-COVID patients exhibited reduced upright high-frequency heart rate variability and low-frequency blood pressure variability compared to controls.
- Patients with initial orthostatic hypotension showed lower supine baroreflex sensitivity than those without abnormalities.
- Postural orthostatic tachycardia syndrome patients had diminished upright high-frequency heart rate variability and baroreflex sensitivity compared to those without abnormalities.
Conclusions:
- Long-COVID is characterized by attenuated cardiac autonomic function, with specific deficits observed in baroreflex sensitivity and sympathetic/parasympathetic modulation depending on the orthostatic phenotype.
- The heterogeneous pathophysiology across long-COVID subgroups underscores the need for personalized therapeutic strategies.
Purpose:
Long-coronavirus disease (long-COVID) is associated with initial orthostatic hypotension and postural orthostatic tachycardia syndrome. Whether altered autonomic tone underlies these abnormalities is unknown. We compared autonomic function between patients with long-COVID and healthy controls, and within patients with long-COVID with different orthostatic hemodynamic phenotypes.
Methods:
Patients with long-COVID (n = 94; F = 76; 42 years [36, 53 years] with initial orthostatic hypotension: n = 40; F = 32; 49 years [39, 57 years]; postural orthostatic tachycardia syndrome: n = 29; F = 26; 39 years [33, 47 years]; or no abnormalities: n = 25; F = 18; 42 years [35, 49 years]), and healthy controls (n = 33; F = 25; 49 years [30, 62 years]) completed a 10-min active stand with beat-to-beat hemodynamics. Heart rate variability, blood pressure variability, and baroreflex sensitivity were calculated as indirect measures of cardiovascular autonomic health. Continuous data (median [95% confidence interval]) were analyzed with Mann-Whitney U tests or Kruskal-Wallis tests with Dunn's corrections.
Results:
Patients with long-COVID had lower upright high frequency heart rate variability (p = 0.04) and low frequency blood pressure variability (p = 0.001) than controls. Patients with initial orthostatic hypotension had lower supine baroreflex sensitivity compared with patients without abnormalities (p = 0.01), and lower supine baroreflex sensitivity (p = 0.001) and high frequency heart rate variability (p = 0.03) than patients with postural orthostatic tachycardia syndrome. Patients with postural orthostatic tachycardia syndrome had lower upright high frequency heart rate variability (p < 0.001) and baroreflex sensitivity (p < 0.001) compared with patients without abnormalities and lower upright low frequency blood pressure variability (p = 0.04) compared with controls.
Conclusions:
Patients with long-COVID have attenuated cardiac autonomic function. Patients with initial orthostatic hypotension have lower supine baroreflex sensitivity. Patients with postural orthostatic tachycardia syndrome have lower upright vascular sympathetic and cardiac parasympathetic modulation. Long-COVID subgroups do not present with homogeneous pathophysiology, necessitating targeted treatment strategies.
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