What is Spontaneous Coronary Artery Dissection: Types, Causes, Symptoms, Treatment, Diagnosis, Epidemiology
What is Spontaneous Coronary Artery Dissection?
Spontaneous coronary artery dissection (SCAD) is a spontaneous tear in the internal membrane of the coronary artery. This leads to lack of oxygen and blood supply to the heart which can later cause heart attacks or irreversible heart damage. Spontaneous coronary artery dissection (SCAD) is a very rare condition and may occur to people who are absolutely healthy and have no illnesses, have no risk factors of any heart disease, or hold no family history of a heart disease. SCAD isn’t easily diagnosed and is often misdiagnosed as panic attack, stress and anxiety, indigestion etc.
Types of Spontaneous Coronary Artery Dissection
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 Hematoma: 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.
Epidemiology of Spontaneous Coronary Artery Dissection
Spontaneous coronary artery dissection (SCAD) is a rare condition reported in 0.2% - 1.1% of patients undergoing coronary angiography. However interpretation of these figures is complicated by the variable inclusion of atherosclerotic plaque associated dissection which is not ’true’ SCAD. The condition affects predominantly young adult patients with mean age of 30-45 years at presentation. At least 70% of Spontaneous coronary artery dissection (SCAD) cases are women and 26 - 38% of cases occur in late pregnancy, peripartum or postpartum. The reported incidence of involvement for the left anterior descending coronary artery (LAD) is 57-75%; the right coronary artery (RCA), 20-32%; the left circumflex (LCx) 4-21% and the left main (LM), <1-21%6, 7. Multi-vessel Spontaneous coronary artery dissection (SCAD) is rare but have been reported.
Symptoms of Spontaneous Coronary Artery Dissection
Symptoms of SCAD include the following:
- Chest pain/tightness
- Upper back/shoulder pain
- Shortness of breath
- Cramping jaw
These are some common symptoms which can lead to wrong diagnosis. Spontaneous coronary artery dissection (SCAD) is difficult to diagnose before it causes a heart attack, because it doesn’t have any warning signs. And although it can cause a life-threatening heart attack, SCAD patients don’t typically have other heart disease risk factors.
Research has shown that:
- Spontaneous coronary artery dissection (SCAD) affects women more often than men; up to 80 percent of patients with SCAD are women
- The average age is 42 years.
- Spontaneous coronary artery dissection (SCAD) patients are typically otherwise healthy, with few heart disease risk factors.
- About 20 percent of women SCAD patients have recently given birth.
Diagnosis of Spontaneous Coronary Artery Dissection
Diagnosis is very crucial in cases of Spontaneous coronary artery dissection (SCAD) as it is often misdiagnosed. The tests are similar to those used to evaluate other heart attacks, such as electrocardiograms and blood tests to detect blood damage. If a heart attack is suspected or diagnosed, it is typically confirmed by taking images of your arteries to look for signs of abnormalities. ECGs and X-rays can easily miss Spontaneous coronary artery dissection (SCAD). The following are the recommended tests for diagnosing SCAD:
- Invasive coronary angiography: A special dye is injected into the arteries so they will show up on imaging tests. Once the dye is released, X-rays are used to create pictures of the arteries.
- Intravascular ultrasound: A special imaging catheter may be passed into your arteries to create sound-wave pictures (ultrasound). This may be conducted in conjunction with the coronary angiography.
- Optical coherence tomography: A catheter equipped with a special light may be passed into your arteries to create light-based pictures. Doctors may perform this test after coronary angiography.
- Cardiac CT angiography: Cardiac CT angiography may be used in addition to other tests or as a follow-up test to evaluate your condition after spontaneous coronary artery dissection (SCAD).
Is Spontaneous Coronary Artery Dissection Hereditary?
Researchers used the Mayo Clinic SCAD Registry of 412 enrollees to identify five familial cases of Spontaneous coronary artery dissection (SCAD), comprised of three pairs of first-degree relatives (mother-daughter, identical twin sisters, sisters) and two pairs of second-degree relatives (aunt and niece, and first cousins). Researchers believe this is the first study to identify SCAD as an inherited disorder.
Treatment of Spontaneous Coronary Artery Dissection
The goal of the treatment for Spontaneous coronary artery dissection (SCAD) is restoring blood flow to the heart. In some cases the healing occurs naturally. In others, doctors may have to restore blood flow by opening the artery with a balloon or stent, or surgically bypassing the artery.
Suitability of the treatment completely depends on the severity of your condition as well as site and location of the tear along with the signs and symptoms you are experiencing.
Medications may relieve symptoms in some people. Most SCAD patients will be started on a number of medications. Typically, Aspirin, Clopidogrel (Plavix), beta blockers e.g. Bisoprolol, ACE inhibitors e.g. Ramipril. A common saying of heart disease patients is “the new normal” which means you have to relearn what is now normal for your body to feel like. Some of the medications, and combinations of medications that Spontaneous coronary artery dissection (SCAD) patients are prescribed can have side effects as well, and it may be hard to know whether a symptom is caused by medications, the original dissection, the resulting heart attack, or from the treatments of stents or surgery. Not all medications are right for every patient, and you may have to work with your doctor to get the right combination and dosages that work best for you.
Percutaneous intervention with stenting can restore flow in the true lumen, relieving ischemia, and seal the dissection, preventing further expansion. The clinical success rate of stenting in patients with Spontaneous coronary artery dissection (SCAD) is over 90%. Single-vessel dissections are usually treated with percutaneous intervention with stenting, while left main dissection, multivessel involvement, or failure of percutaneous interventional procedures may require surgical intervention.
Emergency CABG should be considered for patients where the dissection involves the left main. Procedural success is high because of the relatively young age of the patients, the usual absence of comorbidity and of coronary atherosclerosis, and calcification.
Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndromes and as such, although many cases are described, there remains little reliable information on the epidemiology, optimal clinical and interventional management and outcomes of this condition. There has been little systematic research to date into Spontaneous coronary artery dissection (SCAD), although a current international collaboration seeks to systematically address some of the key questions about this condition.