A number of cardiac abnormalities have been reported in ME/CFS in research studies - these are summarised and referenced in the Research section of the (2016) MEA purple book (abstract below). We can send a copy of this book to your GP, or your consultant, if you live in the UK and supply the MEA with contact details.
One reason why some people with ME/CFS have abnormalities relating to pulse rate (especially palpitations) and low blood pressure (hypotension) is because a key part of the autonomic nervous system (that regulates pulse rate and blood pressure) is quite often involved in ME/CFS. And in some cases this also results in a specific problem called POTS (postural orthostatic tachycardia syndrome) - which produces dizziness, palpitations, feeling lightheaded and sometimes even fainting.
Again, there is detailed information on the diagnosis of POTS, and a summary of key research papers in the MEA purple book
We also have a new MEA information leaflet covering all aspects of POTS relating to ME/CFS
From the Research section of the MEA purple book
5:5 Cardia Function
Although cardiac symptoms, such as palpitations and postural hypotension, may be the result of autonomic dysfunction, new research indicates that there could also be a role for impaired cardiac function.
Using magnetic resonance cardiac tagging – a novel technique that assesses myocardial wall function in vivo – Hollingsworth
et al (2012) found that patients with ME/CFS have markedly reduced cardiac mass and blood pool volumes, particularly end-diastolic volume. This results in significant impairments in stroke volume and cardiac output compared to controls.
A ‘small heart syndrome’, with small left ventricular size and low cardiac output, has been suggested to lead to poor physical stamina and chronic fatigue (Miwa and Fujita 2011; Peckerman
et al 2003).
Autonomic symptoms, including orthostatic intolerance. Autonomic symptoms are very common in ME/CFS, and orthostatic intolerance refers to an inability to sustain upright activity. Symptoms of orthostatic intolerance occur after standing up from a recumbent or resting position or after prolonged standing. They include light-headedness, spatial disorientation, feeling faint, sweating, palpitations and fainting. It is important to identify postural autonomic symptoms in patients because these patients are more likely to become bed-bound due to the fact that standing up makes them feel much worse.
Autonomic symptoms can be assessed using the Orthostatic Grading Scale, which allows a quantification of symptoms in relation to standing. Scores of 4 or above are considered to be consistent with orthostatic intolerance. Scores of 9 and above are consistent with orthostatic hypotension. Orthostatic grading scale:
http://www.meducator3.net/algorithm...thostatic-grading-scale-schrezenmaier-et-al-0
Those who have postural dizziness together with a history of loss of consciousness should be assessed, diagnosed and managed according to the NICE syncope guideline (National Institute for Health and Care Excellence 2010) and the European Society of Cardiology guideline (European Society of Cardiology 2009). This may involve formal autonomic testing and tilt table testing. Ideally, this should include continuous beat-to-beat heart rate and blood pressure measurement in order to detect subtle blood pressure changes.
Table 9
Postural orthostatic tachycardia syndrome
Postural orthostatic tachycardia syndrome (PoTS) sometimes forms part of autonomic nervous system dysfunction in ME/CFS (Hoad
et al 2008). PoTs is defined as symptoms of orthostatic intolerance associated with an increase of heart rate from supine to upright position of > 30 beats per minute (or 40 beats per minute in the 12-19 year age group) or with a heart rate of > 120 beats per minute on standing. Clinical evaluation should therefore include a response to standing.In the recent British Journal of Cardiology review of patients with PoTS and their experience of healthcare in the UK, Kavi
et al (2016) found that 81% of respondents were between the ages of 18 and 49 years and 92% were female. The most common symptoms at presentation were fatigue (91%), light-headedness, dizziness or presyncope (90%) and palpitations (86%). Syncope or blackouts were experienced by 58%. Other commonly presenting symptoms (in over 40%) included difficulty thinking (often described as brain fog), physical weakness, visual disturbances, breathlessness, vertigo, shakiness, chest pain, sweating, bloating, symptoms of anxiety, poor sleep, daily headache, acrocyanosis (purple-blue discolouration of hands and lower limbs), tingling in peripheries, nausea, abdominal pain, heat and exercise intolerance and ‘coat hanger’ pain (thought to be due to ischaemia of neck and shoulder muscles).Research aimed at characterising ME/CFS patients with or without PoTS found that those with PoTS were younger, less fatigued, less depressed and had reduced daytime somnolence (Lewis
et al 2013a). They also had greater orthostatic intolerance and autonomic dysfunction. Those with PoTS may require further investigation and consideration for therapy to control heart rate (Lewis
et al 2013a).Further evidence relating to the important subgroup of ME/CFS patients who also have PoTS comes from Nijs and Ickmans (2013). For a review of PoTS, see Benarroch (2012) and Kavi
et al (2016). NB: In patients presenting with chronic fatigue and/or orthostatic intolerance, low ferritin levels and hypovitaminosis D may be present, especially in those with postural tachycardia (Antiel
et al 2011).
Dr Charles Shepherd
Hon Medical Adviser, MEA