Associated conditions

Some other conditions and diseases, such as Fibromuscular Dysplasia (FMD) and rare connective tissue disorders, such as Vascular Ehlers-Danlos Syndrome, Marfan Syndrome and Loeys-Dietz Syndrome, have been found to be associated with SCAD (NHS information on connective tissue disorders). More common connective tissue disorders, such as hypermobility, have also been found in SCAD patients. Research is ongoing to discover what the links might be.

It’s important to note that not all SCAD patients are diagnosed with another condition, so having SCAD does not necessarily mean you will have any of the conditions below.

Once diagnosed with SCAD, the current consensus recommendation is that a head to hip scan should be done to look for abnormalities of other arteries in the body. (European Society of Cardiology SCAD position paper 2018).

However, it is important to realise that important abnormalities in other arteries which require specific treatment or monitoring are unusual.

Furthermore, unless a patient shows any clinical features of hereditary connective tissue disorders, the current recommendation is that genetic testing is not required.

An editorial commentary on a paper from the Mayo Clinic was been published in November 2020 looking at SCAD and autoimmune diseases. This essentially finds no definite link between autoimmune disease and SCAD suggesting where these occur together it is more likely to be a coincidence rather than a causal relationship.”

The information below provides a brief overview of the conditions. For in-depth information, please go to the websites of the organisations that specialise in these conditions, some of which are listed here.

It is important to bear in mind when looking at the following conditions that there is no evidence to suggest that any of them cause or are caused by SCAD.

We’ve also included information about Heart Failure. In most SCAD survivors the heart muscle injury following a SCAD heart attack is small and heart failure would not be expected, but in a few patients the injury is larger and some of these patients may experience symptoms of heart failure.

All medical content has been approved by Dr David Adlam, Senior Lecturer, Department of Cardiovascular Sciences, University of Leicester and lead researcher on the SCAD research project at Glenfield Hospital/University of Leicester.

If you know of any websites you think would be useful for patients please email

Fibromuscular dysplasia (FMD)

Fibromuscular dysplasia (FMD) is described as a ‘non-atherosclerotic, non-inflammatory disease of arterial walls’. It is an uncommon disease in the population but is found quite frequently in SCAD survivors. It occurs where there is abnormal cell growth in arteries and is most commonly found in renal (kidney), cervico-cephalic (neck-head) and iliac (pelvic) arteries.

FMD causes narrowing and/or enlargement of one or more medium-sized arteries. This can sometimes reduce blood flow and affect the function of organs.

FMD is more common in women (approx 80-90%) but does occur in men too. Current figures indicate that it mainly affects arteries leading to the kidneys, but is also found in arteries leading to the neck and brain, heart, abdomen, arms and legs.

The cause is unknown, but it is not an inflammatory condition, nor is it caused by atherosclerosis (furring of the blood vessels). It is not known whether there is a hormonal factor. Some people who have FMD are asymptomatic but others may have complications such as high blood pressure or artery dissections.

Causes of FMD

Researchers have not yet found the cause of FMD, but female hormones, genetics and trauma to artery walls may play a role. The Cleveland Clinic says about 7-11% of cases are inherited and about 25% of patients with FMD have had a family member with an aneurysm.

Types of FMD

The European Society of Cardiology SCAD position paper 2018 says FMD has two sub-types: multifocal and focal (sometimes called unifocal).

In Focal FMD arteries have distinct focal lesions (damage) or tubular stenosis (narrowing).

In Multifocal FMD patients have multiple lesions and the artery has the appearance of a ‘string of beads’, caused by alternating areas of widening and narrowing.

Symptoms of FMD

Most SCAD survivors with FMD have no symptoms and require no treatment or follow-up imaging. A very small number of patients with SCAD and FMD will be symptomatic. These rare symptoms include:

FMD in the carotid or vertebral arteries – headaches, including migraines, a swooshing or pulsating noise in the ears, neck pain and lightheadedness. It is important to remember these are common symptoms and will not be due to FMD in most cases.

FMD in the renal arteries often causes high blood pressure and/or poor kidney function.

FMD of the mesenteric arteries (arteries to the intestines) may cause abdominal pain after eating and weight loss (this is very uncommon).

Treatments for FMD

If you have no symptoms you will not need treatment. Indeed in most SCAD survivors FMD is an incidental finding and does not require either follow-up imaging or any specific treatment.

A very small number of SCAD patients may require surveillance imaging (for example for small arterial swellings called aneurysms).

In some patients with cervical FMD, antiplatelet medication (eg aspirin) may be prescribed to prevent blood clots.

If you have high blood pressure you may need to take blood pressure medication. Very occasionally high blood pressure in patients with renal FMD may not respond to treatment and specific treatment to the artery may be needed. In the context of SCAD with FMD this is extremely rare.

If you have frequent headaches, especially migraines you may be offered medication to help.

How FMD is diagnosed

FMD may be found during an X-ray or scan for another problem, and imaging such as an angiogram, MRA (magnetic resonance angiography) or CTA (computed tomography angiography) can confirm a diagnosis. 


Studies have reported FMD in SCAD patients in 11-86% of patients. The range narrows to 41-86% after excluding three studies where less than 50% of patients were screened. Prevalence of FMD may differ depending on the proportion of patients screened and the screening method used. FMD may be more frequent in SCAD patients with more tortuous (curvy/winding) coronary arteries. The most important thing to understand is that although FMD is quite common in SCAD patients, it is rarely of clinical importance. If you are found to have FMD, discuss it with your doctors but in most cases this is not something to worry about. (Source: European Society of Cardiology SCAD position paper 2018)

We asked if SCAD could be FMD of the heart arteries. SCAD expert Dr David Adlam told us that recent data from genetic studies suggests there’s an overlap (the first common variant found also occurs in FMD and migraines) but they don’t seem to have the same genetic signature. So they are more likely to be related and overlapping rather than the same thing. Patients with primary FMD (FMD as a primary diagnosis) don’t seem to have SCAD – SCAD seems to be rare in that cohort.

Useful links

UK Kidney Association 

FMD info from the UK Kidney Association

Clinical info from the UK Kidney Association

Mayo Clinic 

John Hopkins

Cleveland Clinic information on FMD

Brain Facts 

National Organisation for Rare Diseases (NORD)

Hypertension magazine Revisiting Fibromuscular Dysplasia

First International Consensus on the diagnosis and management of fibromuscular dysplasia

FMD expert Dr Heather Gornik discusses FMD and SCAD

Fibromuscular Dysplasia Society UK & Ireland

Fibromuscular Dysplasia Society UK & Ireland Youtube channel

FMD UK & Ireland Facebook group

Fibromuscular Dysplasia Patient Association Belgium

FMD-BE’s closed Facebook group

Fibromuscular Dysplasia Society of America

Fibromuscular Dysplasia Association of Australasia

Rare Connect FMD Community

Video from first FMD Information Day January 2019 What is FMD?

Ehlers-Danlos Syndromes (EDS)

Ehlers-Danlos Syndromes are a range of connective tissue disorders, which are rare.

Connective tissue is found between other tissues in the body, such as skin, ligaments, blood vessels and internal organs, and they support and protect the body.

Causes of EDS

EDS is caused by gene mutations that make connective tissue weaker. It can be inherited but sometimes appears by chance in someone with no family history.

Types of EDS

There are 13 types of EDS, including Hypermobility EDS, Classical EDS and Vascular EDS.

Symptoms of EDS

Symptoms can vary depending on the type of EDS, but can include:

Hypermobile joints

Stretchy skin

Fragile skin that breaks or bruises easily

Patients with Vascular EDS may have aneurysms (bulges in arteries).

Some people with EDS have mild symptoms while for others they can be disabling. Some of the rare types can be life limiting and life threatening.

How EDS is diagnosed

Various tests can be done to diagnose Classical and Vascular EDS, including genetic testing, skin biopsy and ECG.


There is no cure for EDS, but medical professionals can offer help to manage symptoms.


A very few SCAD patients have been diagnosed with some types of EDS but it is unknown what the link is.

Useful links

Ehlers-Danlos Support UK

NHS information about EDS

Rare Connect Ehlers-Danlos Community

Annabelle’s Challenge, charity for vEDS patients 

London North West University EDS Diagnostic Service

Sheffield Children’s Hospital EDS Service (diagnoses children and adults) 

Marfan Syndrome

Marfan Syndrome is a genetic condition that affects connective tissue. It is mainly an inherited condition but it sometimes appears by chance in someone with no family history.

Connective tissue is found between other tissues in the body, such as skin, ligaments, blood vessels and internal organs, and they support and protect the body. 

Causes of Marfan Syndrome

Marfan Syndrome is caused by a gene mutation that causes an increase in a protein called fibrillin, which in turn causes connective tissue problems, such as parts of the body being able to stretch abnormally.

Symptoms of Marfan Syndrome

Some patients with Marfan Syndrome have obvious features, such as being very tall and thin with long limbs, a curved spine, flexible joints, flat feet and stretch marks that are not connected to weight gain or loss.

Other symptoms include an enlarged aorta and aortic dissection, sudden lung collapse and eye problems including detached retina and early glaucoma or cataracts.

How Marfan Syndrome is diagnosed

Various tests including an ECG, CT (computerised tomography) and MRI (magnetic resonance imaging) scans are used to diagnose Marfan Syndrome. Genetic testing can also be carried out.


There is no cure for Marfan Syndrome, but medical professionals can offer help to manage symptoms.

SCAD and Marfan Syndrome

Very occasional SCAD patients have been diagnosed with Marfan Syndrome but it is unknown what the link is.

Useful links

The Marfan Foundation 

NHS information on Marfan Syndrome 

Mayo Clinic information on Marfan Syndrome 

Marfan Trust 

Great Ormond Street 

Cardiac Risk in the Young 

Loeys-Dietz Syndrome

Loeys-Dietz Syndrome is a genetic condition that affects connective tissue. 

Connective tissue is found between other tissues in the body, such as skin, ligaments, blood vessels and internal organs, and they support and protect the body. 

Causes of Loeys-Dietz Syndrome

Loeys-Dietz Syndrome is caused by a gene mutation.

Symptoms of Loeys-Dietz Syndrome

Some patients with Loeys-Dietz Syndrome have obvious features, such as widely spaced eyes and malformation of the spine in the neck. Other symptoms include an enlarged aorta and aortic dissection.

How Loeys-Dietz Syndrome is diagnosed

Various tests including an echochardiogram, CT (computerised tomography) and MRI (magnetic resonance imaging) scans are used to diagnose Loeys-Dietz Syndrome. Genetic testing can also be carried out.


There is no cure for Loeys-Dietz Syndrome, but medical professionals can offer help to manage symptoms.

SCAD and Loeys-Dietz Syndrome

A paper was published in September 2020 confirming a link between patients with genetically confirmed Loeys-Dietz Syndrome and SCAD.

Useful links

Loeys-Ditz Sydrome Foundation

The Marfan Foundation

John Hopkins Medecine

What is Heart Failure?

The heart is a specialised pump that delivers oxygen-rich blood around the body, keeping vital organs supplied with oxygen. Heart failure is a term that is used to describe when the pumping action of the heart has become impaired. It is also referred to as congestive cardiac failure, cardiomyopathy or Left Ventricular Systolic Dysfunction.

Primarily heart failure occurs when the heart muscle becomes weak, there can be a variety of reasons for this, these are the more common ones:

  • Heart attack, also referred to as Myocardial Infarction

This occurs when a blood vessel that supplies blood to the heart muscle narrows or completely blocks. Part of the heart muscle is then weakened due to the interruption of oxygen-rich blood flowing through it.

Although they can lead to heart failure, the following are not particularly relevant for SCAD patients who, in general, are otherwise fit and healthy:

  • High blood pressure also referred to as Hypertension

The majority of people do not realise they have high blood pressure until they have an event or it is picked up incidentally.  Left untreated it can lead to stiffening of the coronary arterial walls that in turn increases the pressure within the heart which means it has to work harder which can lead to heart failure.

  • Heart valve disease

Integral to the heart’s function is a one-way system of blood flow controlled by heart valves (mitral, aortic, tricuspid, pulmonary) and as the body ages one or more valves may develop a problem, being too tight so blood cannot flow properly or too loose, this increases pressure within the heart chambers which can lead to muscle damage.

  • Irregular or rapid heart beat

If left untreated for any length of time this can cause the heart muscle to weaken.

  • Viral cardiomyopathy

When a virus attacks the heart muscle this can lead to heart failure.

  • Other causes include excess alcohol, amphetamine/cocaine use, genetic causes.

So why do some SCAD patients get Heart Failure?

When a SCAD event occurs it often leads to a heart attack. In most SCAD survivors the heart muscle injury following a SCAD heart attack is small and heart failure would not be expected, but in a few patients the injury is larger and some of these patients may experience symptoms of heart failure.

Symptoms of Heart Failure

  • Breathlessness (with exertion or at rest – variable to each individual).
  • Oedema (fluid retention or swelling) – caused by fluid building up in the body as a result of the heart not adequately pumping. This may show as swelling in lower limbs, abdomen , fluid can also collect in the lungs making breathing more difficult.
  • Orthopnoea – this is the inability to lie flat due to fluid collecting in the lungs.
  • Fatigue – feeling excessively tired and fatigued, due to inadequate oxygen supply to the muscles. (This is of course a common symptom and may be due to causes other than heart failure.)

It’s important to note that you may not necessarily experience any of these symptoms.

How is Heart Failure diagnosed?

  • Echocardiogram – non-invasive ultrasound test to look at the heart structure and function. Sometimes an ejection fraction (EF) is noted or it may be described as mild/moderate or severely impaired, it’s important to note that normal EF is usually more than 50% (average figures are between 55% and 70%), no-one has 100%.
  • CMR – Cardiovascular Magnetic Resonance Imaging, also referred to as cardiac MRI, it’s a non-invasive assessment of the function and structure of the cardiovascular system.

How is Heart Failure treated?

The mainstay of treatment is medication because the scientific research shows that a combination of medications can stabilise and improve the function of the heart as well as improve the long term outcomes.

The medications that are used to treat Heart Failure are:

  • Ace Inhibitors – Lisinopril, Ramipril, Enalapril, Captopril – reduces the body’s ability to retain sodium, which is linked to fluid retention.
  • ARBs – Candesartan, Valsartan – works in a similar way to ACE inhibitor, often prescribed as an alternative if patients get the side effect of dry cough with ACE inhibitor.
  • Sacubitril/Valsartan – Entrestro – a relatively new drug to Heart Failure, currently only prescribed to patients who have severe LV dysfunction.
  • MRA – Eplerenone, Spironolactone – shown to improve long-term outcomes in patients with severe LV Dysfunction.
  • Beta-blocker – Bisoprolol, Carvedilol, Nebivolol – these are the only licensed beta-blockers for use in Heart Failure. They help the heart to pump in a more efficient way by remodelling the cells within the muscle of the heart and slowing it down.
  • Diuretics – Furosemide, Bumetanide, reduce water retention in the body.

All of the above can potentially have side effects, however it’s important not to just stop any prescribed medications, if you think you are having problems then discuss this with your cardiologist/Heart Failure specialist nurse or GP.

Living with Heart Failure

Managing your symptoms can really help to improve your quality of life, being mindful with fluid intake, especially important if you are experiencing symptoms of fluid retention. Taking your prescribed medications will also benefit you long term as there is evidence to show that they improve the heart function and reduce your chances of hospital admission due to worsening Heart Failure. 

Find out if you have a local Heart Failure specialist nurse in your area that you can be referred to, they will be able to support you through the difficult times with symptom management, medications and direct you to other services such as cardiac rehabilitation and benefits advice.


Ensuring that you have adequate travel insurance is essential when travelling abroad; this can be hard to navigate at times when trying to decide on which policy to take out.  It is a good idea to shop around for the best price to suit your needs/budget but always bear in mind how much excess you would want to pay in the event that you had to use it.

Also you may find that if you are travelling with a partner/companion they may not be covered if the trip needs cancelling ahead of schedule if it is as a result of your pre-existing condition.

There are very few restrictions on air travel for cardiac patients; however you can clarify with your cardiologist/GP. A useful document to refer to is fitness to fly for passengers with cardiovascular disease.

It is also useful to consider where you are travelling to so you can plan ahead of the trip in the event of an emergency such as researching where the nearest cardiology hospital is and what provisions are in place if you needed to be transported quickly.

What you can do to help yourself if you have heart failure

Work with your clinical team and heart failure nurse. For some patients weighing yourself daily can be helpful – this is to detect for any sudden increases that may be associated with increasing fluid retention, a fluctuation of 1-2lb either way is normal but an increase of more than this over a few days can be a signal that things may be deteriorating and should prompt you to seek advice from the healthcare team that are looking after you.

Taking your prescribed medications – very important to improve the long-term prognosis.

Physical activity – pacing yourself according to how you feel each day, strenuous exertion, such as heavy lifting, should be avoided but in general exercising within your limits is good for heart failure patients.

Sleeping – if you have trouble breathing when you are lying down try using 2-3 pillows to prop yourself up.

Rest– when you are tired.

Eating healthily – aim for freshly prepared foods wherever possible, reduce but preferably cut salt from your table, there’s lots of information available online around healthy eating, the BHF is a good starting point.

Salt and fluid – reducing added salt in the diet is generally good advice and is particularly important in patients with heart failure as this makes fluid retention worse. For fluids, the guidance for more significant Heart Failure patients is to restrict fluid intake to 1.5 litres per day, this is especially important for those patients who are struggling with fluid retention. Discuss with your clinical team and heart failure nurse to see if this applies to you.

Stop smoking – everyone knows the detrimental effect that this has on health outcomes, if you do smoke then think about trying to stop, you can discuss this with your GP or Practice Nurse, there are lots of NHS funded initiatives to support patients who want to stop smoking.

Useful links

British Heart Foundation

NHS information on Heart Failure 

Ejection Fraction information

Thanks to Julie Harris, Heart Failure Specialist Nurse, for writing this information and to Dr David Adlam for reviewing it.




Blood vessel diseases

Diseases that cause inflammation of the blood vessels, such as lupus and polyarteritis nodosa, have been associated with SCAD.

Useful links

NHS information on Lupus 

Lupus UK 

Vasculitis UK