Kentaro Tamura

Frozen elephant trunk technique and partial remodeling for acute type A aortic dissection

OBJECTIVE The aimed to describe the frozen elephant trunk (FET) technique and partial remodeling (PR) for acute type A aortic dissection (ATAAD), considering the long-term prognosis on the basis of our 13 years of experience. METHODS There were 80 consecutive patients (mean age: 66.4 years) with an FET and PR technique for ATAAD between September 1997 and February 2010. We indicated a PR for all 80 patients without dilatation of the sinuses and a FET for 20 patients with a distal entry in the descending aorta, 14 patients with a dilatation more than 4cm on the distal arch and 46 patients with a narrow true lumen younger than 70 years with a narrow true lumen. During moderate hypothermic circulation with selective cerebral perfusion and distal perfusion from the femoral artery, a stent graft (mean diameter: 27.7mm, mean length: 9.9mm, mean distal depth: thoracic vertebra (Th) 6.0th) was inserted through the transected proximal aortic arch. The plication of the sinotubular junction (N=42) or partial remodeling for right and/or non-coronary cusp (N=38) was performed after total arch replacement with a four-branched prosthesis. RESULTS Four patients died in hospital. Early morbidity included two (2.5%) strokes but no spinal cord injury. In long-term follow-up (mean 94.6 months), five patients died of non-aortic events and two re-operations (Bentall and stent grafting to the descending aorta) were required. No patients had patent false lumen on the stent graft and residual aortic regurgitation, according to late follow-up computed tomography (CT) and echogram. The 10-year survival was 75% and the overall 10-year re-operation free rate on the thoracic aorta was 95%. CONCLUSION FET and modified PR techniques could be effective for improving the long-term outcome on the distal and proximal aorta in an ATAAD.

Long-term results of the frozen elephant trunk technique for extended aortic arch disease

OBJECTIVES This study describes the long-term safety and effectiveness of extended aortic arch replacement with the frozen elephant trunk technique from our 12 years of experience. METHODS Between September 1997 and September 2008, 156 patients (mean age 67.9 years) with different pathologies from the aortic arch to the extended descending aorta in 100 dissections (acute A/acute B/chronic B=66/26/8) and 56 thoracic arteriosclerotic aneurysms (TAAs) had the frozen elephant technique performed upon them. During moderate hypothermic circulation with selective cerebral perfusion, the stent graft was inserted through the transected proximal aortic arch with trans-oesophageal echo guidance. RESULTS Six patients (3.2%) (acute A/acute B/chronic B/TAA=3/2/0/1) died in hospital. Postoperative morbidity induced four (2.6%) strokes (acute A/acute B/chronic B/TAA=2/0/0/2) and three (2.0%) spinal injuries (paraplegia in two and transient paraparesis in one) (acute A/acute B/chronic B/TAA=0/0/1/2). In the long-term follow-up (mean 63.3 + or - 39.2 months, maximum 144 months) 16 patients died. The survival rate was 99.3%, 86.5% and 74.9% at 1, 5 and 10 years, respectively. An additional operation was performed in 15 (9.4%) (ascending aorta/aortic root/descending aorta/abdominal aorta=1/2/5/7) including three stent-graft-related events (2.1%), and the additional repair proved successful. A follow-up computed tomography (CT) image was available for 96.0% (143/149) of patients who survived longer than 12 months. The size of false lumen or aneurysm increased in four patients, was unchanged in 20 patients (14.0%), shrank in 66 (46.2%) and was completely obliterated in 55 (37.1%). CONCLUSIONS The frozen elephant technique could be an attractive treatment for extended aortic arch disease to the extended descending aorta for acute aortic dissection as well as arteriosclerotic aneurysm.

In situ replacement for mycotic aneurysms on the thoracic and abdominal aorta using rifampicin-bonded grafting and omental pedicle grafting.

BACKGROUND The objective of this report is to discuss the efficacy of in situ replacement for treating mycotic aneurysm, particularly using rifampicin-bonded grafts and omental pedicle grafts, on the basis of our 7 years of experience. METHODS Between December 2003 and December 2010, we performed surgical treatments in 23 patients (for the thoracic aorta in 6 patients, for the thoracoabdominal aorta in 8 patients, and for the abdominal aorta in 9 patients; 7 emergency, 10 urgent, and 6 elective operations) with mycotic aneurysm by using rifampicin-bonded grafting and omental pedicle grafting. RESULTS One patient died in hospital because of local recurrent infection. One patient required an additional operation on another aortic site, and 3 patients had spinal cord injuries (2 transient and 1 permanent). Overall survival at 5 years was 95%, and the rate of freedom from aortic events at 5 years was 86%. CONCLUSIONS In situ replacement using rifampicin-bonded grafting and omental pedicle grafting is effective for treating mycotic aneurysms of the thoracic and abdominal aorta.

Relationship between coagulation cascade, cytokine, adhesion molecule and aortic aneurysm.

OBJECTIVES Patients with aortic aneurysm (AA) were in the chronic inflammatory condition and are often combined with disseminated intervascular coagulation. Recent studies demonstrated that atherosclerosis was inflammatory disease. AA and severe atherosclerosis with ulcer formation contain macrophages and T lymphocytes and accelerate the production of interleukin (IL)-2, which activates lymphocytes and lead to further adhesion of leukocytes. This study was designed to clarify the coagulation condition, cytokine, adhesion molecule, and collagen turnover in patients with AA and finally their relationship with the aneurysmal size. METHODS Thrombin-antithrombin III complex (TAT), plasma D-dimer, serum type III procollagen peptide (PIIIP), serum soluble IL-2 receptor (sIL-2R), Free tissue factor pathway inhibitor (TFPI), and soluble intercellular adhesion molecule (ICAM-1) were measured preoperatively around the same period when computed tomography (CT) was taken in 17 patients with AA (mean age: 72.2 years). Age-matched (mean age:70 years) volunteers were served as control. Maximum aneurysmal size was measured by CT and aneurysmal volume was also calculated from CT. RESULTS AA patients showed significantly higher level in preoperative TAT and D-dimer compared to control (TAT: control 2.5+/-1.2 ng/ml, pre 7.2+/-4.5,ng/ml; P=0.0001; D-dimer: control 107+/-46 U/ml, pre 420+/-256 U/ml; P=0.0001). Cytokine also showed higher level preoperatively (sIL-2R: control 398+/-132 U/ml, pre 735+/-260 U/ml; P=0.0001). TFPI showed higher value preoperatively (control 22.9+/-4.9 ng/ml, pre 30.4+/-6.9 ng/ml; P=0.003). PIIIP (collagen turnover) showed no difference between the groups (P=0.0057) and neither did ICAM-1(P=0.0087). TAT (r=0.799, P=0.0001), D-dimer (r=0.56, P=0.0193), sIL-2R (r=0.709, P=0.0021), PIIIP (r=0.561, P=0.00239), and sICAM-1 (r=0.505, P=0.046) level showed positive correlation with aortic aneurysmal size and also TAT D-dimer, and sIL-2R levels were positively correlated with aneurysmal volume (r=0.714 P=0.0013, r=0.556 P=0.00204, r=0.693 P=0.0029, respectively). CONCLUSIONS AA patients were in the hypercoagulation and inflammatory condition. Aneurysmal size was well correlated with TAT, D-dimer, sIL-2R, PIIIP, and sICAM-1, suggesting that these markers could be good diagnostic and monitoring tool for the disease progression.

Early entry closure for acute type B aortic dissection by open stent grafting

PurposeWe describe the long-term efficacy of early entry closure for acute type B aortic dissection by open stent grafting based on long-term results and changes in the false lumen on enhanced computed tomography (CT).MethodsWe performed open stent grafting for acute type B aortic dissection in 28 28 patients between 1998 a 2008. They included 14 patients with complicated type B aortic dissection (11 patients with limb and/or visceral ischemia and 4 patients with impending rupture). Uncomplicated type B aortic dissection was present in 14 patients, including 4 patients with an ulcer-like projection and 10 patients who had stable dissection with a patent false lumen.ResultsTwo patients who had the ischemic type died within 30 days. Postoperative complications occurred in two patients, including one case of paraplegia and one of mediastinitis. Two more deaths occurred during a median follow-up period of 45 months (range 6–114 months), with one related to open stent-graft infection and one due to pneumonia. The overall survival rate 5 years after open stent grafting was 77%. According to follow-up by CT, the false lumen was completely thrombosed and obliterated in all 26 patients with stent grafts.ConclusionEarly entry closure for both complicated and uncomplicated acute type B aortic dissection with an open stent graft has an acceptable early outcome and provides a high aortic remodeling rate.

Branched graft inversion technique for distal anastomosis in total arch replacement.

Distal anastomosis during total arch replacement for thoracic aortic aneurysm is at times difficult, and bleeding from it is a serious problem because of its limited surgical exposure. We have modified a new procedure, the branched graft inversion (BGI) technique. We investigated the effectiveness of our technique by comparing it with the conventional stepwise technique. Between January 2008 and August 2011, 40 patients, divided into two groups of 20 each, underwent elective total arch replacement. One group underwent surgery using BGI; the stepwise technique was performed on the remaining 20 patients. Our modified BGI technique offers easy and secure distal anastomosis under good surgical procedure, resulting in shorter durations of operation, cardiopulmonary bypass, and circulatory arrest (455.1±101.3 min versus 354.7±49.3 min, p<0.001; 248.2±46.6 min versus 199.7±28.2 min, p<0.001; 76.6±27.7 min versus 61.6±10.4 min, p=0.029, respectively). As a result, this technique could be a useful in performing total arch replacement.