Focal intramural hematoma as a potential pitfall for iatrogenic aortic dissection during subclavian artery stenting: A case report

BACKGROUND: Iatrogenic aortic dissection (IAD) is a rare but fatal complication of interventional treatment for the proximal supra-aortic large vessels. Several cases of IAD after endovascular treatment of subclavian artery have been reported. Nevertheless, the pathogenesis of IAD is still unclear. Here we report a patient with IAD following a balloon expandable stent implanted into the left subclavian artery (LSA). CASE SUMMARY: An 84-year-old man with a history of hypertension was admitted to the Neurology Department of our hospital complaining of dizziness and gait disturbance for more than 1 mo. Computed tomography angiography of the head and neck showed severe stenosis at the proximal LSA and the origin of the left vertebral artery. Magnetic resonance diffusion-weighted imaging of the brain revealed subacute infarctions in cerebellum, occipital lobe and medulla oblongata. He suffered a Stanford type B aortic dissection after the proximal LSA angioplasty with a balloon expandable stent. Thoracic endovascular aortic repair was performed immediately with the chimney technique and he was discharged 20 d later. After exploring the pathogenesis with multimodal imaging analysis, an easily neglected focal intramural hematoma (IMH) in the aorta near the junction of the LSA was found to be the main cause of the IAD. The risk of IAD should be sufficiently evaluated according to the characteristics of aortic arch lesions before the proximal LSA angioplasty. CONCLUSION: Focal aortic IMH is a potential risk factor for IAD during a seemingly simple stenting of the proximal LSA.