"…18% of patients with coronary function testing-confirmed ANOCA meeting diagnostic criteria for #MECFS. Invasive cardiopulmonary exercise testing (iCPET) in patients with [both] reveals a primary peripheral, not cardiac, limitation to exercise."
#Cardiology
journals.physiology.org/doi/10.1152/...
journals.physiology.org
Hemodynamic Phenotyping in ME/CFS and ANOCA: Complementary Insights from Coronary Function Testing and Invasive Cardiopulmonary Exercise Testing | American Journal of Physiology-Heart and Circulatory Physiology | American Physiological Society
This single-center cohort study sought to evaluate the association between Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Angina with Non-Obstructive Coronary Arteries (ANOCA), by determining the observed frequency of ME/CFS among patients with ANOCA diagnosed by coronary function testing (CFT). Additionally, we performed an exploratory analysis of the diagnostic utility of invasive cardiopulmonary exercise testing (iCPET) in ME/CFS patients with CFT-confirmed ANOCA, with the aim of identifying the predominant physiological mechanism responsible for exertional limitation in this population. Systematic medical record review of 261 patients with CFT-confirmed ANOCA was performed using standardized diagnostic criteria to identify concurrent ME/CFS diagnosis. ME/CFS was identified in 47 patients, representing an observed frequency of 18%. The only statistically significant difference between ANOCA patients with and without ME/CFS was a higher frequency of connective tissue disease in the ME/CFS group (p = 0.0221). In a separate cohort of 27 patients with ME/CFS who underwent iCPET, 24 patients (89%) had CFT-confirmed ANOCA. The diagnosis of ANOCA by CFT prompted a change in medical management in 81% of patients in this cohort. iCPET revealed a primary peripheral limitation to exercise, characterized by impaired peak systemic oxygen extraction despite normal peak oxygen delivery. This study demonstrates a clinically significant association between ME/CFS and ANOCA. These findings underscore the clinical value of CFT in patients with ME/CFS and exertional chest pain and highlight iCPET as a complementary tool for hemodynamic phenotyping in this population. Prospective studies incorporating simultaneous CFT and iCPET with molecular phenotyping are warranted.
![Published on: 9 December 2025
In the Long Run, Misleading Participants Will Harm More Than Help in Long COVID Research
Todd E. Davenport, Professor & Chair University of the Pacific, Workwell Foundation
Other Contributors:
Staci R. Stevens, Exercise Physiologist
Mark A. Faghy, Professor
Jessica DeMars, Respiratory Physiotherapist
J. Mark Van Ness, Professor & Chair
Respect for persons, beneficence, and justice are bedrock ethical principles in science. They are especially important when studying vulnerable populations. Billias et al. argue that deception is necessary to assure the internal validity of their exercise study involving people living with long COVID.[1] Here, we assert the use of deception is ethically indefensible and scientifically unnecessary in this population. It undermines informed consent, increases risks for harms, exploits the vulnerability of participants, and erodes trust in science and health care, all while exploring a question that already has been asked and answered satisfactorily enough to inform clinical recommendations.
Physical activity is a common trigger for post-exertional malaise (PEM),[2 3] which is common in people living with long COVID.[4] PEM involves an impaired recovery response from exertion that is distinct from deconditioning.[5 6] The hallmark of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is PEM. Exercise is no longer recommended in contemporary clinical guidance for ME/CFS, because an accumulation of evidence from research and lived experience suggests it is likely to cause avoidable harms.[7] Exercise prescription without adequate safeguards for PEM even may be considered negligent practice. The protocol acknowledges people living with PEM often worsen with exercise dosages that may be appropriate for other conditions.[1] Several of the authors of this protocol also previously published a systematic review acknowledging risks of exercise in people with long COVID related to PEM.[8] However, the author…](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:43rudsv62fuwsmnk7oppgtdy/bafkreidl77x7uweergov5gcuvlzqo7ehnvalbag3u44hniwvoh5uuc2ccy)
