Complete Fracture of a Chimney Stent in the Left Common Carotid Artery after Thoracic Endovascular Aortic Repair for Thoracic Aneurysm

Correspondence To the Editor: We reported a rare complication after thoracic endovascular aortic repair (TEVAR) with a chimney stent. A 68‑year‑old patient with no history of chest or back pain history presented to our hospital for evaluation of the endograft for TEVAR of a thoracic aneurysm approximately 4 years previously. Computed tomography angiography showed significant type Ia endoleak and the endograft had severe compression and migration [Figure 1a]. The chimney stent was an 8 mm × 39 mm Palmaz Genesis balloon‑expandable stent (CordisCo, Bridgewater, NJ, USA). Interestingly, it was unobstructed but completely fractured [Figure 1b]. One part of the chimney stent was lost in the thoracic aneurysmal sac and one part was embedded in the wall of the aorta; however, the remaining part was located in the orifice of the left common carotid artery (LCCA) and kept the LCCA unobstructed [Figure 1c]. During the TEVAR in 2010, the endograft size was selected according to the aortic diameter as assessed by CT scan [Figure 1d] of the proximal landing zone with 20% oversizing. The chimney stent in the LCCA was implanted to extend the proximal landing zone and a 42 mm × 216 mm Zenith was fixed distal to the innominate artery and completely covered the aneurysm. The chimney stent was parallel with the endograft in the aorta for a length of approximately 20 mm. The final angiography showed the thoracic aneurysm was successfully repaired without endoleak and endograft migration [Figure 1e]. Postoperatively, medical management included β‑blockers and calcium antagonists administrated in combination to maintain systolic blood pressure at <140 mmHg. Dual antiplatelet therapy (aspirin [100 mg once per day] and clopidogrel [75 mg once per day]) was recommended for the first 3 months, and lifelong aspirin therapy was recommended thereafter. However, the patient did not have a good blood pressure control and needed follow‑up in the vascular outpatient clinic. Careful surveillance was recommended based on an asymptomatic condition; because of the high risk for mortality, re‑intervention was also recommended. A hybrid strategy would be necessary if aorta‑related symptoms occurred. Written informed consent was obtained from the patient. The chimney technique with selective or bail‑out conditions was used to extend the proximal landing zone in TEVAR. Mangialardi et al. reported the rate of chimney stent fracture was 3.8%, with a patency rate of 89.3% and a type Ia endoleak rate of 20%. [1] Although both self‑expanding and balloon‑expandable devices could be …