Dysautonomia, but Not Cardiac Dysfunction, Is Common in a Cohort of Individuals with Long COVID, 2023, Tabacof, Putrino et al.

Dysautonomia, but Not Cardiac Dysfunction, Is Common in a Cohort of Individuals with Long COVID
Tabacof, Laura; Wood, Jamie; Breyman, Erica; Tosto-Mancuso, Jenna; Kelly, Amanda; Wilkey, Kaitlyn; Zhang, Chi; Putrino, David; Kontorovich, Amy

Despite the prevalence of dysautonomia in people with Long COVID, it is currently unknown whether Long COVID dysautonomia is routinely accompanied by structural or functional cardiac alterations. In this retrospective observational study, the presence of echocardiographic abnormalities was assessed.

Left ventricular (LV) chamber sizes were correlated to diagnostic categories and symptoms via standardized patient-reported outcome (PRO) questionnaires. A total of 203 individuals with Long COVID without pre-existing cardiac disease and with available echocardiograms were included (mean age, 45 years; 67% female).

Overall, symptoms and PRO scores for fatigue, breathlessness, quality of life, disability, anxiety and depression were not different between those classified with post-COVID dysautonomia (PCD, 22%) and those unclassified (78%). An LV internal diameter at an end-diastole z score < −2 was observed in 33 (16.5%) individuals, and stroke volume (SV) was lower in the PCD vs. unclassified subgroup (51.6 vs. 59.2 mL, 95% C.I. 47.1–56.1 vs. 56.2–62.3). LV end-diastolic volume (mean diff. (95% CI) −13 [−1–−26] mL, p = 0.04) and SV (−10 [−1–−20] mL, p = 0.03) were smaller in those individuals reporting a reduction in physical activity post-COVID-19 infection, and smaller LVMI was weakly correlated with worse fatigue (r = 0.23, p = 0.02).

The majority of individuals with Long COVID report shared symptoms and did not demonstrate cardiac dysfunction on echocardiography.

Link | PDF (Journal of Personalized Medicine)

 

I am curious. Has anyone checked whether hypovolemia is associated with dysautonomia or Long Covid? I don't know how anyone is tested for hypovolemia.

Edit : Spelling/typo

 

The paper says —

LV = left ventricle
LVMI = left ventricular mass index
EDV = end-diastolic volume
SV = stroke volume

Refs 16 and 17 are —

Dysautonomia in hypermobile Ehlers–Danlos syndrome and hypermobility spectrum disorders is associated with exercise intolerance and cardiac atrophy (2021, American Journal of Medical Genetics Part A)

Cardiac Origins of the Postural Orthostatic Tachycardia Syndrome (2010, Journal of the American College of Cardiology)

Please note the 2010 paper's unfortunate recommendation to use the term "Grinch syndrome".

See also —

Diagnosis and management of postural orthostatic tachycardia syndrome (2022, CMAJ)

Blood Volume Status in ME/CFS Correlates With the Presence or Absence of Orthostatic Symptoms: Preliminary Results (2018, Frontiers in Pediatrics)

Renin-Aldosterone Paradox and Perturbed Blood Volume Regulation Underlying Postural Tachycardia Syndrome (2005, Circulation)

And there is a 2019 thread https://www.s4me.info/threads/blood-volume-and-red-blood-cell-volume-in-me-cfs.17305/

 

Flat/collapsible IVC on ultrasound is an indicator of hypovolaemia, but assume it wouldn't be particularly indicative here unless it was either very full or very flat? TTE would be a more accurate measurement for preload and RA volume, but I can't see measurements in the paper's results...

 

No mention of whether the participants would meet ME/CFS criteria or not.

 

The abstract does not say what 'classified with dysautonomia' means.
I have no idea.

 

2.1. Study Design

This was an observational study using retrospectively obtained electronic health record (EHR) information and patient-reported outcomes (PROs). [...]

2.2. Participants

Adults attending the Long COVID clinic at Mount Sinai Hospital were included. The Long COVID clinic is an interdisciplinary clinic consisting of physicians (primary care and a range of subspecialties including physiatry and cardiology), physical therapists, dietitians and researchers.

Inclusion criteria were EHR diagnosis of Long COVID, defined as experiencing new, returning or ongoing health problems 4 or more weeks following initial COVID-19 infection in the absence of any specific organ damage using standard clinical testing protocols, and having a transthoracic echocardiogram (TTE) assessment performed at Mount Sinai Hospital > 28 days following diagnosis with COVID-19. Individuals were excluded if they had a diagnosis of heart failure, cardiomyopathy or dysautonomia prior to COVID-19 infection.

2.5. Classification of Clinically Diagnosed Dysautonomia

EHRs (primary care or cardiology progress notes, “problem list”) were manually reviewed to identify whether individuals with Long COVID were diagnosed with dysautonomia/PCD specifically as documented by their treating cardiologist or physician or were otherwise “unclassified” (no stated diagnosis of dysautonomia in the EHR). Participants were classified by the research team as having dysautonomia if their treating cardiologist or physician documented this diagnosis in the EHR, with supporting evidence including symptoms and clinical/historical features, and/or formal testing including a tilt table test, active stand test, quantitative sudomotor axon reflex test, thermoregulatory sweat test, or using heart rate variability. Members of the research team were not involved in the initial diagnosis of dysautonomia.

 

Another words whatever somebody wanted it to mean.
Seems a complete waste of time.

 

Reviewers 1 and 3 sound like they agree with you.

Authors replied —