The endothelium is a delicate membrane that lines the heart and blood vessels on the surface of the heart (coronary arteries).
In endothelial dysfunction, there is no blockage of the coronary arteries, but the blood vessels narrow (constrict) when they should be opening (dilating), which can cause chest pain.
Symptoms of endothelial dysfunction include:
- Chest pain or discomfort (angina) that worsens during physical activity or emotional stress (the main symptom)
- May be worse during menstrual periods in females
- Shortness of breath
- Tiredness
Endothelial dysfunction usually occurs before the development of atherosclerosis, which is abnormal thickening and hardening of arterial walls that can lead to a stroke or heart attack.
What Causes Endothelial Dysfunction?
The exact cause of endothelial dysfunction is unknown but most cardiac risk factors contribute to it.
Risk factors for endothelial dysfunction may include:
- Being female
- About two-thirds of people who develop endothelial dysfunction are female
- Being overweight or obese
- Sedentary lifestyle
- Smoking
- High stress
- Other health conditions
How Is Endothelial Dysfunction Diagnosed?
Endothelial dysfunction is diagnosed with a patient history and physical examination.
Usually, when people see a doctor with chest pain the doctor will run tests to look for blockages in the coronary arteries, but since endothelial dysfunction is a type of nonobstructive coronary artery disease, in which the arteries not blocked, it can be difficult for patients to get to a correct diagnosis.
Testing for endothelial function includes a two-step process:
- The drug adenosine is injected into one of the coronary arteries which causes the small vessels of the heart to dilate, and the amount of blood flow is measured
- Then the drug acetylcholine is injected, which causes dilation in the large arteries, and the amount of blood flow is again measured
Other tests may include:
- Stress test with imaging
- Coronary angiogram
- Computerized tomography (CT) coronary angiogram
- Positron emission tomography (PET) scan
- Carotid duplex ultrasound
- Pulse wave velocity (PWV)
- Pressure pulsation signal
What Is the Treatment for Endothelial Dysfunction?
Treatment to manage endothelial dysfunction includes lifestyle changes and medications when needed.
Lifestyle modifications to manage endothelial dysfunction may include:
- Lose weight
- Don’t smoke
- Eat a healthy, balanced diet
- Stress management
- Exercise regularly
Medications used to manage endothelial dysfunction may include:
- Nitrates
- Help to open narrowed blood vessels, increasing blood flow to the heart and minimizing chest pain
- Calcium channel blockers
- Helps relax and widen blood vessels
- ACE inhibitors
- Used to treat high blood pressure and heart failure
- Statins
- Used to help repair the endothelium and reduce cholesterol levels in the blood, preventing plaque build-up
- Aspirin
- May prevent blood clots and may also help damaged endothelium cells to heal
- Lipid-lowering drugs
- Used to manage cholesterol levels
- Alpha and beta blockers
- Used to manage blood pressure
- Newer therapies include ranolazine, aminophylline and experimental therapies
Another treatment option is external counter pulsation (ECP) therapy. The patient lays on a table or bed and pressure cuffs are fitted to the patient's thighs, hips, and calves. The cuffs inflate and deflate in sync with the patient's heart rhythm, providing the heart with extra oxygen-rich blood while in the resting phase. This extra blood supply helps stimulate growth of surrounding blood vessels, which improves the supply of blood to the heart.
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https://stanfordhealthcare.org/medical-conditions/blood-heart-circulation/endothelial-dysfunction.html
https://www.cedars-sinai.org/programs/heart/clinical/womens-heart/conditions/endothelial-function-testing.html