Long COVID, ME/CFS and PoTS. Measured, not guessed.
What to Expect
If every test has come back normal, it may be because the abnormality only appears when you stand up, or in the minutes after you exert yourself. Nobody has looked there yet. We do.
Long COVID and ME/CFS share almost the same picture
Post-viral onset after Epstein-Barr and glandular fever has been recognised for decades. COVID-19 produced the same pattern at scale.
❋ Why the standard workup comes back normal
Most people who come to us have already had the bloods, the ECG, often an echocardiogram. Everything was normal, and they were sent away with a label of anxiety, deconditioning, or nothing at all.
That is not anybody's fault. A resting ECG measures the heart lying still. A cuff on a seated arm gives one number, twice. Neither can detect a circulation that only fails after a person stands up, or only fails in the minutes after they have exerted themselves.
That is where the abnormality lives in long COVID and in ME/CFS. It is why the tests keep coming back clear, and it is exactly what our assessment is built to provoke and measure.
❋ An overlapping structure
The overlap is not a coincidence and it is not controversial. A large proportion of people with long COVID meet the established diagnostic criteria for ME/CFS, and the defining feature is the same in both: post-exertional malaise, a delayed worsening that arrives a day or two after activity rather than during it.
The physiology is also the same. An early metabolic threshold, the body switches to an unsustainable fuel system at a much lower workload than expected. Impaired autonomic recovery after exertion. And, very often, a heart that is not filling adequately when upright, which limits what it can deliver regardless of how fit the person is.
What Makes Our Tests Different
Standard orthostatic testing asks you to stand up from rest. That is the right first test and it identifies many people.
We can also apply the orthostatic challenge to a circulation that has already been destabilised by a short bout of exercise. For a substantial group, a stand from rest is not a strong enough provocation, and the problem only appears when the two are combined.
Throughout, we measure central aortic pressures and beat-by-beat pulse contour, using gold-standard vascular testing equipment and simultaneous ECG, not just cuff readings. Blood pressure can look perfectly normal while the volume the heart ejects with each beat is falling steadily. A cuff cannot see / read this.
Ask Yourself, Could This Be You ?
Usually worse on standing, in heat, after meals, and in the hours or days after activity.
Light-headedness on standing, or near-fainting
Racing or pounding heartbeat when upright
Exhaustion out of proportion to what you did
A crash a day or two after activity, not during it
Brain fog and difficulty concentrating
Breathlessness or chest discomfort
Headaches, nausea, shakiness, cold or clammy hands
Worse in hot weather or a hot shower
Worse after skipping a meal or on a low-salt diet
Cannot stand still for long, but better walking
Training that used to be easy is now impossible
Sleep that does not refresh you
Why the answer matters: two conditions, two opposite treatments
This is the single thing testing is for. No consultation, questionnaire or history can reliably tell these two apart, because they describe themselves the same way. A measurement can.
-
Structured reconditioning works. A progressive programme that begins recumbent or semi-recumbent and advances slowly, always below your measured threshold.
In the trial that established this approach, published by Fu and Levine in Hypertension in 2011, a majority of patients no longer met the criteria for PoTS after three months, with increased blood volume, increased cardiac mass and a lower standing heart rate.
Known as the Levine or CHOP protocol. It depends entirely on knowing where your threshold actually sits.
-
Progressive exercise is the wrong treatment, and pushing through makes things worse. The approach here is energy management: staying inside your envelope, and expanding it only as the envelope itself changes.
NICE guideline NG206, published in 2021, no longer recommends graded exercise therapy for ME/CFS and places energy management at the centre of care.
This is where a measured pacing ceiling earns its keep, because the whole approach depends on a number.
What applies either way
A pacing ceiling that is measured, not estimated. Age-predicted maximum is commonly 15 to 20 bpm away from a person's real maximum, and heart rate zones calculated from it can be wrong by a wide margin. In this group, an estimated ceiling fails the people who can least afford it.
Volume expansion. Salt and fluid loading, at levels agreed with your doctor and where there is no reason to avoid it. Inexpensive, not a prescription, and we can measure whether it worked by repeating the orthostatic test and your hydration levels using bioelectrical impedance analysis.
Compression. Abdominal compression reduces orthostatic tachycardia and symptoms in PoTS, published in JACC in 2021, with more recent work showing abdominal-only garments are effective. Blood pooling in the abdomen is the target, which is why waist-high garments outperform calf-length ones.
Finding the treatable things that get missed, iron deficiency above all, which contributes independently to both fatigue and orthostatic symptoms.
Information your doctor can prescribe from. Where medication is warranted, the choice differs depending on which physiological pattern you have. That decision belongs to your doctor, and the measurement is what lets it be made on data.
Objective documentation of capacity and postural tolerance for ACC, insurers, schools and employers, and a baseline to measure change against later.
StandardThe Assessments
Most people have all three, usually across two visits. They can be taken separately if your doctor wants one specific question answered.
-
Cardiopulmonary exercise test with breath-by-breath gas analysis and blood lactate. Gives you a measured first ventilatory threshold, which is the heart rate ceiling your pacing should be built on.
-
Active stand from true supine rest, then a post-exercise orthostatic challenge, against published diagnostic criteria. Central haemodynamics and pulse contour captured throughout.
-
Up to 24 hours of three channel ambulatory ECG, plus artefact-controlled heart rate variability at rest, through exertion and across recovery.
-
Gold standard assessment - Continuous beat-to-beat blood pressure and stroke volume at 70 degrees head-up. This is the definitive study for PoTS and delayed orthostatic hypotension, because it removes the leg muscle pump that confounds every standing test.
What You Walk Away With
You will be asked to exert yourself, but only within limits agreed with you beforehand. We do not perform maximal testing on anyone with post-exertional symptoms without discussing it first and obtaining your consent. Bring comfortable clothing and any previous reports, ECGs or blood results.
1: A pacing number you can actually use
A measured heart rate ceiling, with instructions for applying it to work, study or sport, and adjusted for posture so it does not simply alarm at you all day.
2: A written report for your GP or specialist
with every measurement, every trace and the reasoning set out. Written to be read by a clinician, not filed unread.
3: Home monitoring set up
chest strap and watch configured to your own numbers, with a simple rule for deciding whether today is a training day.
4/5: A clear list of what has been excluded + Objective evidence
which is often the most useful page in the report. that what you are experiencing is real and measurable. For many people that is the part that matters most, and it is the part that carries weight with schools, employers and insurers.
For referrers
We accept referrals from general practice, sport and exercise medicine, cardiology, rheumatology, paediatrics, immunology and allied health, and are most often useful in four situations.
A post-viral fatigue patient who needs a pacing threshold. A measured ventilatory threshold rather than a percentage of predicted maximum. Adherence improves, because the number is theirs.
A patient whose active stand was equivocal. We can apply the orthostatic challenge after a bounded exercise provocation, with central haemodynamic monitoring throughout, and from September with continuous stroke volume on tilt.
A patient who needs functional capacity documented for ACC, an insurer, a school or an employer.
An athlete whose performance has dropped without explanation. Gas exchange, thresholds, central pressures and rhythm in a single session.