Spontaneous coronary artery dissection (SCAD) is a rare cause of acute myocardial infarction characterized by a non-traumatic separation of the coronary arterial wall. It most commonly affects younger women and the left anterior descending artery. SCAD results from an intimal tear or bleeding of vasa vasorum that leads to the formation of a false lumen filled with blood. This can cause the artery to narrow and restrict blood flow. SCAD is increasingly recognized and can be caused by conditions affecting connective tissue or hormonal factors during pregnancy. Angiography is used to diagnose SCAD but findings may be subtle, with long diffuse narrowing being most common. Management involves conservative treatment but revascularization may be needed for ongoing ischemia

1. CORONARY DISSECTION

2. SPONTANEOUS CORONARY ARTERY DISSECTION
• NON ATHEROSCLEROTIC SCAD
• ATHEROSCLEROTIC SCAD

3. SPONTANEOUS CORONARY ARTERY DISSECTION
(SCAD)
• a non-traumatic and non-iatrogenic separation of the coronary arterial wall
• a rare cause of acute myocardial infarction
• It is more common in younger patients and in women

4. PATHOLOGY AND PATHOPHYSIOLOGY
• An intimal tear or bleeding of vasa vasorum with intra-medial haemorrhage has been
propose
• Result in creation of a false lumen filled with intramural hematoma
• Pressure-driven expansion of the false lumen by an enlarging hematoma may lead to
luminal encroachment and subsequent myocardial ischemia and infarction.
• On the other hand, can result in extensive dissection lengths, especially in the presence of
arterial fragility from predisposing arteriopathies,

5. • In pregnant or early postpartum women, dissection may be a consequence of increased
physiological hemodynamic stresses or from hormonal effects weakening the coronary
arterial wall
• Intramural hematoma involving the outer two-thirds of the media is common.
• Histologically, an inflammatory reaction (e.g., eosinophilic infiltrates) in the adventitia has
been described, suggestive of periarteritis that may breakdown the medial-adventitial layer
predisposing the artery to dissection

6. DISEASE ASSOCIATIONS AND CAUSES
• Fibro postpartum status
• Muscular dysplasia (FMD)
• Multiparity (≥4 births)
• Connective tissue disorders
• Systemic inflammatory conditions
• Hormonal therapy

7. EPIDEMIOLOGY
• Spontaneous coronary artery dissection (SCAD) is the cause of acute coronary syndrome
(ACS) in 0.1 to 4 percent of cases
• SCAD has been reported to account for nearly a quarter of cases of ACS in women ≤50 years
old
• Classically thought to affect young women, SCAD is now increasingly recognized to also occur
in older and postmenopausal women
• Men can also present with SCAD (<10 to 15 percent of cases); however, mechanistically, these
are more likely atherosclerotic in origin than non-atherosclerotic

8. CLINICAL MANIFESTATIONS
• Patients with non-atherosclerotic spontaneous coronary artery dissection (NA-SCAD) usually
present with symptoms and signs characteristic of acute myocardial infarction
• Chest pain
• arm pain,
• neck pain,
• nausea or vomiting,
• diaphoresis,
• dyspnea, and back pain
• Life-threatening ventricular arrhythmias occurred in 4 to 14 percent

9. FINDINGS COMMONLY SEEN ON ANGIOGRAPHY
• The left anterior descending coronary artery was the most frequently affected vessel
(approximately 40 to 70 percent of cases)
• The most commonly observed angiographic type was 2 (67 percent)

10. DIAGNOSIS
• Criteria for the angiographic definition include the presence of a non-iatrogenic dissection
plane in the absence of coronary atherosclerosis, with typical changes of radiolucent intimal
flap and contrast staining- stereotypical changes were seen in only <30 percent of non-
atherosclerotic -SCAD
• The majority of NA-SCAD had long and diffuse narrowing on angiography due to intramural
hematoma, and this appearance was frequently unrecognized on angiography leading to
under-diagnosis of this condition.

11. ANGIOGRAPHIC CLASSIFICATION
• Type 1: Pathognomonic contrast dye staining of arterial wall with multiple radiolucent lumen,
with or without the presence of dye hang-up or slow contrast clearing
• Type 2: Diffuse long and smooth stenosis that can vary in severity from mild stenosis to
complete occlusion
• Type 3: Mimics atherosclerosis with focal or tubular stenosis and requiring optical coherence
tomography (OCT) or intravascular ultrasound (IVUS) to differentiate the cause.

12. TYPE -1

13. TYPE 2

14. TYPE 3

15. MANAGEMENT
• Conservative therapy is the preferred strategy after the diagnosis is secured
• Patients presenting with acute myocardial infarction who have symptoms of ongoing
ischemia or hemodynamic compromise should be considered for revascularization with PCI or
coronary artery bypass grafting
• Many patients have been managed with long-term aspirin , beta blocker, and one year of
clopidogrel, with the addition of a statin in patients with dyslipidemia

16. ACTIVITIES AFTER SCAD
• Patients are encouraged to join cardiac a rehabilitation program after discharge.
• A multidisciplinary approach including exercise rehabilitation, psychosocial counselling,
dietary and cardiovascular disease education, and peer group support
• To reduce arterial shear stress, target exercise heart rate is recommended at 50 to 70 percent
of heart rate reserve, and systolic blood pressure during exercise is limited to <130 mmHg
• Women are instructed to avoid lifting weights >20 to 30 pounds, and men to avoid >50
pounds.

17. ATHEROSCLEROTIC SCAD
• Atherosclerotic SCAD is a mechanistically distinct variant of SCAD and is typically limited in
extent by medial atrophy and scarring

18. DISSECTION DURING PTCA
• Some dissections result from overly vigorous attempts at guidewire passage, but most are
due to the "controlled injury" induced by inflation of the dilation catheter
• The occurrence of dissection cannot be predicted by preintervention analysis of lesion
morphology or plaque composition by intracoronary ultrasound (IVUS)

19. INTIMAL TEARS OR DISSECTIONS FOLLOWING PTCA
• Type A – Luminal haziness
• Type B – Linear dissection
• Type C – Extraluminal contrast staining
• Type D – Spiral dissection
• Type E – Dissection with reduced flow
• Type F – Dissection with total occlusion

21. • The increased risk of abrupt closure and MI associated with a large dissection has led to the
routine use of stenting for any dissection.
• Most cases of acute closure occur within minutes of the final balloon inflation, but subacute
closure occurs up to hours later in 0.5 to 1.0 percent of cases, typically as the heparin
anticoagulation wears off
• Stents can reverse abrupt closure in more than 90 percent of cases. However, some patients
still require bypass surgery after stenting because of persistent coronary occlusion or
dissection resulting in ischemia