Introduction:
Spontaneous coronary artery dissection (SCAD) is a tear or separation
within the coronary artery wall forming an intraluminal hematoma
reducing downstream blood flow leading to myocardial ischemia (MI)(Figure 1A-C)1 . Intraluminal hematomas may
develop from ”inside-out” due to endothelial-intimal injury or
”outside-in” due to injury within the vasa vasorum leading to bleeding
in the wall. The subsequent false lumen from either mechanism can extend
and compress the true lumen to cause MI [2]. Unlike other luminal
etiologies of MI, SCAD is not caused by atherosclerotic plaque rupture,
coronary intervention, or trauma [3]. With significant MI from
intraluminal hematoma, patients can present with signs and symptoms that
mimic MI including chest pain with and without radiation, dyspnea,
nausea and vomiting. It can also include elevated troponin with
electrocardiogram (ECG) changes consistent with ST segment elevation or
non-ST segment elevation MI. The diagnosis is made when other etiologies
of acute coronary syndrome (ACS) are ruled out and there is an
angiographic evidence of non-iatrogenic or non-atherosclerotic
radiolucent intimal flap and contrast staining [1]. Left anterior
descending (LAD) artery is the most commonly affected branch of the left
main coronary [4]. Severe stenosis can lead to heart failure as well
as cardiogenic shock amongst other post-MI complications including
ventricular arrhythmias, ventricular free wall or septal wall rupture.
If angiography is inconclusive, then intracoronary imaging with optical
coherence tomography or intravascular ultrasound may be considered
before repeat angiography [5].
The etiology of SCAD is thought to be multifactorial without a clear
underlying cause. Risk factors associated include fibromuscular
dysplasia (FMD), peri and postpartum period, hormonal fluctuations, and
arteriopathies. SCAD is a rare cause of ACS, although when present,
there is a higher prevalence in young females without cardiac risk
factors [6]. Stable patients are treated conservatively with
medication while percutaneous coronary intervention (PCI) and coronary
artery bypass graft are reserved for severe stenosis and acute change in
hemodynamics. Use of antiplatelet therapy remains controversial as
medications such as acetylsalicylic acid (i.e. aspirin) and P2Y12
receptor blockers can worsen intraluminal hematoma. Dual antiplatelet
therapy is recommended for those who undergo stent placement [5].
Similarly, guideline directed medical therapy is initiated for new onset
of heart failure. Review of literature reveals 90% recovery within one
month with coronary computed tomography angiography [5]. Many cases
of SCAD have been reported in young females with ischemic symptoms and
angiographic findings in the distal LAD but only few cases highlight
proximal coronary involvement. We present a case of a young woman with
extensive left main and proximal LAD SCAD requiring intervention.