What is SCAD?

This is hopefully a non-scientists' explanation of SCAD, and is not intended to be a substitute for clinical evaluation or diagnosis. If you - or a loved one - have been diagnosed with SCAD, this page will hopefully reinforce some of the things you've been told by your own doctor.Spontaneous Coronary Artery Dissection (SCAD) is an unpredictable event with patients usually experiencing a sudden, unexpected heart attack. It can affect all age groups and is recognised as a cause of heart attacks in young adults. Both sexes can be affected but it is more common in women, in particular during or soon after pregnancy. Sadly some cases of SCAD are fatal. SCAD results from an acute bleed into the vessel wall of a coronary artery creating a false lumen (a lumen is the term for the inside of a blood vessel, the 'tube' down which the blood is supposed to flow. This accumulation of blood compresses the true lumen, restricting or preventing blood flow to the heart muscle. Little is currently known about the underlying cause, optimal treatment and long term prognosis of SCAD.The name SCAD can be broken down as follows:

  • Spontaneous: there is no injury, apparent disease or other direct cause for the dissection of the coronary artery, it appears to "just happen".
  • Coronary: dissections can happen in other parts of the body, but when it happens in a blood vessel supplying the heart muscle tissue, it can cause a heart attack.
  • Artery: Arteries supply blood (carrying oxygen) to a muscle or organ of the body, veins carry the blood back to the lungs for more oxygen.
  • Dissection: the doctors' term for when the layers of a blood vessel separate, in this case because of the blood which gets in between the layers of the vessel wall.

SCAD may result in:

  • Angina (chest pain)
  • Myocardial Infarction (heart attack)
  • Sudden Cardiac Arrest

SCAD types:

  • Dissection flap: where a split or separation develops between the layers of artery wall and a loose flap of tissue causes a blockage and impedes normal blood flow
  • Intramural haematoma: where the artery wall is damaged and a collection of blood leaks into the tissue causing a swelling which blocks blood flow

One or both types may be present.  One or more coronary arteries may be affected.  Treatment of SCAD The optimal treatment strategy for SCAD is largely undetermined but the primary goal of the interventionist is to open up any artery blockage to restore blood flow and minimise heart muscle damage – you may hear cardiologists say “Time is muscle” and it really is... the sooner treatment can be started, the better the chance of damage limitation.  However, treatment will vary according to the individual patient’s circumstances: the type of SCAD event and the severity of presenting symptoms.  Sometimes if there is good flow in the affected artery it may be best to leave it to heal by itself.  Following diagnosis of SCAD during the coronary angiography, treatment may be:

  • Conservative i.e. medically managed with no surgical intervention
  • Percutaneous Coronary Intervention (PCI) i.e. stent placement
  • Coronary Artery Bypass Grafting (CABG – “cabbage”)

Content topics: