Case Report: Spontaneous coronary artery dissection with intramural hematoma involving the LCX and the left main segment between the bifurcation and the ostium

Background Spontaneous coronary artery dissection (SCAD) may initially present as acute coronary syndrome and be managed under a presumed ST-segment elevation myocardial infarction pathway before the vessel wall diagnosis is recognized. Management is particularly challenging when extensive intramural hematoma involves left main or bifurcation-related anatomy. Case Presentation A 47-year-old woman presented with recurrent chest pain, cardiac biomarker elevation, and inferior/posterior ST-segment abnormalities. Before SCAD was recognized, recurrent inferior ST-segment elevation was treated under a presumed STEMI pathway, including thrombolysis. Angiography showed a distal left circumflex coronary artery (LCX) double-lumen-like appearance with TIMI grade 3 flow. Intravascular ultrasound (IVUS) demonstrated a focal distal LCX intimal disruption/fenestration; extensive intramural hematoma involving the imaged distal, mid, and proximal LCX; the LCX ostium; and the imaged left main segment between the bifurcation and the ostium, with marked true-lumen compression. Given hemodynamic stability and the absence of refractory ischemia, conservative management was selected after balancing the anatomical concern against the procedural risks of revascularization. At approximately 3 months, angiography and IVUS showed disappearance of the distal angiographic abnormality and resolution of intramural hematoma within the reassessed segments. During follow-up through approximately 6 years after discharge, the patient reported no recurrent chest pain or unplanned rehospitalization. Conclusion IVUS clarified lesion morphology and extent not fully defined by angiography, illustrating the complementary roles of angiographic and vessel wall information in case-specific risk assessment. Subsequent resolution does not establish treatment efficacy or support general treatment recommendations. The initiating event and direction of hematoma spread could not be determined from the available imaging.