Table 2

Key differential features among obstructive and non-obstructive coronary artery diseases leading to clinical presentation of ACS

Obstructive CADMyocardial infarction in absence of obstructive coronary artery disease
Mean age61 years58 years
Specific causesAtherosclerotic plaqueAtherosclerotic plaque disruptionSCADTakotsubo
Vascular dysfunction
Incidence within ACS75%–80%1%–5%1%–4%
35% among women <50 years of age
<2% (whites)
5%–8% (Asians) Microvascular
Specific features and triggersTypical finding is more frequent single-vessel CAD in STEMI while multivessel CAD in NSTEMIFrequently observed in young women who died suddenlyStrong association with fibromuscular dysplasia
Triggered by pregnancy/partum emotional stress extreme physical activity
It has a temporary course with yearly recurrence rate <1%
Triggered by emotional (mostly negative life events) and physical stressors in 70% of cases
Inherited thrombophilia particularly factor V Leiden (5% of general population) increases the infarct risk by a factor of 1.7–3.7.Very frequent among Asian people and observed in 50% of patients with coronary atherosclerosis
Additional diagnostic toolsFFR for non-culprit lesions
OCT/IVUS in case of uncertainness
Echocardiography contrast CMRITEE
Check for hypercoagulable disorders
Intracoronary acetylcholine test coronary flow reserve in response to adenosine corrected TIMI frame count
  • ACS, acute coronary syndrome; CAD, coronary artery disease; CMRI, cardiac MRI; FFR, fractional flow reserve; IVUS, intravascular ultrasound; (N)STEMI, (non) ST-segment elevation myocardial infarction; OCT, optical coherence tomography; SCAD, spontaneous coronary artery dissection; TEE, trans-oesophageal echocardiography; TIMI, thrombolysis in myocardial infarction.