A 53-year-old man with chief complaints of chest pain and right lower extremity numbness was diagnosed with Stanford type A aortic dissection (DeBakey type Ⅰ), with a re-entry tear 3 cm distal to the subclavian artery, and decided to undergo emergency surgery at another hospital. The right femoral artery (FA) was not palpable. Through median sternotomy, arterial cannulas were placed in the right axillary artery (AX) and right FA, with an 8-mm branch of a 24-mm prosthetic woven graft (Hemashield Woven Aortic Branch, Angled 4 Branch Graft, GETINGE, Sweden). Venous cannulas were placed into the superior and inferior vena cava. An 8-mm prosthetic vascular conduit was placed in the right AX to facilitate selective cerebral perfusion (SCP). After aortotomy, the primary entry tear was located at the distal to left subclavian artery (LSCA). SCP was initiated through the brachiocephalic artery (BCA), left common carotid artery (LCCA), and right AX conduit. The descending aorta at the tear was narrow, and an 18-mm woven graft (Intergard Woven, Straight, GETINGE, Sweden) was selected to make a 5 cm ET. Distal anastomosis was performed near the left subclavian artery using an outside felt strip. Blood supply to the lower body was started from the side branch. In case of proximal anastomoses, an outside felt strip and inside 8-mm strip of autologous pericardium were used. After removing the cross clamp, the cervical branches were anastomosed. Cardiopulmonary bypass was withdrawn, and decannulation was performed. However, the left and right FA pressures were approximately 50 mmHg lower than that of the aortic root. The pressure of the right AX did not decrease, suggesting ET anastomotic stenosis. Subsequently, transoesophageal echocardiography showed stenosis at the graft anastomosis in the descending aorta, which was dilated with an occlusion balloon; however, lower extremity blood pressure did not improve. Aorto-femoral bypass was performed from the 10-mm side branch of the 24-mm aortic graft to the right FA with a ring graft (GORE® INTERING® Vascular Graft, GORE, USA; Fig. 1a). Following bypass, the right FA was palpable and left FA pressure increased, even though stenosis at the distal graft anastomosis persisted. The postoperative course was uneventful. Although postoperative magnetic resonance imaging showed a stenotic lesion of approximately 4 cm in size within the graft from the distal anastomosis, the patient was discharged as there were no haemolytic findings.
His haemoglobin was approximately 12 g/dL 16 years after the initial surgery, though it rapidly decreased to 8 g/dL in approximately 1 year. His renal function continually deteriorated, and exertional respiratory distress was observed. Similar to the initial surgery, CT revealed stenosis (Fig. 1b) as the ET and AX bypass were patent. Based on the patient’s blood analyses (Table 1), chronic intravascular haemolysis caused by mechanical damage owing to the stenotic ET was suspected. Moreover, renal dysfunction was considered to be the effect of long-term haemolysis. We decided to perform diagnostic treatment with TEVAR. The left FA was used, and the prosthetic graft of the aorto-femoral bypass was exposed from the right abdomen. The guidewires were inserted in these two locations. Aorto-femoral bypass to the lower limbs was blocked, and the pressure gradient across the stenosis was 60 mmHg. Transoesophageal echocardiography revealed flow in the false lumen; however, compression of the graft by a bulging false lumen was not observed. A balloon catheter (Medtronic REL46 Reliant Stent Graft Balloon Catheter 12Fr, Medtronic, United State) was inflated, which slightly widened the stenosis, and we performed the ballooning aggressively and repeatedly till no more dilation was possible, avoiding rupture of the suture line due to expanding stenosis.
Table 1
T-bil
|
1.1mg/dL
|
Hb
|
8.0g/dL
|
D-bil
|
0.4mg/dL
|
Ht
|
23.6%
|
ALT
|
12U/L
|
Ret
|
7.3%
|
LDH
|
1336U/L
|
Schistocyte
|
(+)
|
DCT
ICT
|
(-)
(-)
|
EPO
Hp
|
33.3mIU/ml
< 10mg/dL
|
T-bil: total bilirubin, D-bil: direct bilirubin, ALT: alanine aminotransferase, LDH: lactate dehydrogenase, DCT: direct Coombs' test, ICT: indirect Coombs' test, Hb: hemoglobin, Ht: hematocrit, Ret: Reticulocyte, EPO: erythropoietin, Hp: haptoglobin |
Thereafter, the main endovascular graft body ZTA 28-28-155 (COOK Zenith Alpha®, COOK® MEDICAL, USA) was inserted from the left FA and deployed immediately distal to the orifice of LCCA (Zone 3 TEVAR). After the stenosis was carefully enlarged, balloon dilatation was performed at the stenosis (Fig. 2a, b). Subsequently, the pressure gradient improved to 50 mmHg. The operative time was 100 min, and the estimated blood loss was 50 mL. Three days postoperatively, dyspnoea on exertion improved, and five days postoperatively, Hb levels increased. On postoperative axial CT, the largest area of the minor axis diameter of the stenotic ET was dilated from 5 to 11 mm (Fig. 3a, b). The patient was discharged seven days postoperatively. There was no recurrence of anaemia two years postoperatively. This study was approved by the ethics review board of our hospital and conforms to the declaration of Helsinki. The patient provided informed consent for publication of this study.