Yukihiko Tamiya

Total arch replacement using aortic arch branched grafts with the aid of antegrade selective cerebral perfusion

BACKGROUND We report our clinical experience with total arch replacement using aortic arch branched graft in an attempt to determine the independent predictors of both in-hospital mortality and neurologic outcome. METHODS We studied 220 consecutive patients who underwent total arch replacement using aortic arch branched graft between May 1990 and June 1999. All operations were performed with the aid of hypothermic extracorporeal circulation, antegrade selective cerebral perfusion, and open distal anastomosis. RESULTS The overall in-hospital mortality rate was 12.7%. Multivariable analysis showed independent determinants of in-hospital mortality to be chronic renal failure, long pump time, participation in early series, and shock. Postoperative permanent neurologic dysfunction was 3.3%. On multivariable analysis, old cerebral infarct and pump time were independent determinants of permanent neurologic dysfunction. The selective cerebral perfusion time had no significant influence on in-hospital mortality or neurologic outcome. The 5-year survival rate including in-hospital deaths was 79% +/- 6%. CONCLUSIONS Selective cerebral perfusion allows increased ease of performance of total arch replacement, a complex and time-consuming procedure, and helps reduce periprocedural mortality and morbidity in patients with aortic arch aneurysm and those with acute aortic dissection.

Extended total arch replacement for acute type a aortic dissection: Experience with seventy patients

OBJECTIVE We sought to report the clinical experience with extended total arch replacement for acute type A aortic dissection and to determine the factors that influence early mortality, late survival, and late reoperation. METHODS Between December 1988 and August 1998, 70 patients underwent emergency graft replacement of both the ascending aorta and the total aortic arch for acute type A aortic dissection. All operations were performed with hypothermic extracorporeal circulation, selective cerebral perfusion for cerebral protection during aortic arch repair, and open distal anastomosis. Concomitant procedures included aortic valve resuspension in 18 patients, composite graft replacement in 10 patients, and coronary artery bypass grafting in 5 patients. RESULTS The early mortality rate was 16% (11 of 70 patients). Multivariable analysis showed that renal-mesenteric ischemia and coronary artery bypass grafting were independent determinants for early death. Survival rates at 3 and 5 years postoperatively, including the early deaths, were 75% +/- 5% and 73% +/- 6%, respectively. Multivariable analysis showed that renal-mesenteric ischemia and en bloc repair were independent determinants for late death. Freedom from reoperation was 91% +/- 4% and 77% +/- 8% at 3 and 5 years, respectively. Multivariable analysis showed that anastomotic leakage was the only significant determinant for late reoperation. CONCLUSIONS Extended total arch replacement for acute type A aortic dissection could be justified in properly selected patients.

Extended aortic replacement for acute type a dissection with the tear in the descending aorta

OBJECTIVE There has been controversy as to the selection of surgical treatments for acute type A dissection with the tear in the descending thoracic aorta, a subtype of acute aortic dissection in which the limited tear is located distal to the left subclavian artery but the dissection extends retrogradely to the ascending aorta. METHODS Total replacement of the ascending aorta and aortic arch was performed in 12 patients with acute type A dissection with the tear in the descending thoracic aorta between March 1991 and the end of September 1995. The indications for total replacement of the ascending aorta and aortic arch were cardiac tamponade, acute aortic regurgitation, cerebral ischemia, and dilatation of the ascending aorta. The operation was performed with the aid of extracorporeal circulation, blood cardioplegia, selective cerebral perfusion, and open distal anastomosis. The surgical procedure used was total replacement of the ascending aorta and aortic arch with a graft provided with three limbs accompanied by resection of the intimal tear in the descending thoracic aorta. RESULTS Hospital death occurred in two patients (16.7%). In both, death was due to dissection/related complications of renal/mesenteric ischemia. The other 10 patients have had uneventful postoperative courses over a mean period of 24 months. CONCLUSIONS Total replacement of the ascending aorta and aortic arch accompanied by resection of an intimal tear distal to the left subclavian artery seems to be justified in selected patients with acute type A dissection with the tear in the descending thoracic aorta.

Protective effect of monoclonal antibodies against LFA-1 and ICAM-1 on myocardial reperfusion injury following global ischemia in rat hearts.

The effects of anti-LFA-1 and anti-ICAM-1 monoclonal antibodies (MAbs) on the reperfusion injury of rat cardiac tissues after global ischemia were studied. Studies were performed using an isolated blood perfused heart preparation in which hearts were subjected to 30 min of global ischemia followed by 40 min of reperfusion. Isolated rat hearts were perfused with blood from an anesthetized support rat with or without anti-LFA-1 or anti-ICAM-1 monoclonal antibody administration (n = 10 in each group). Ventricular function, myocardial tissue water content and myocardial energy status were evaluated in this model. In the control group, ischemia and reperfusion of isolated hearts resulted in a 63.6 +/- 2.7% recovery of left ventricular developed pressure (LVDP) and a 44 +/- 7% increase in coronary vascular resistance compared with pre-ischemic baseline values. Treatment with anti-LFA-1 MAb or anti-ICAM-1 MAb resulted in a 77.2 +/- 1.5% and a 80.4 +/- 3.0% recovery of LVDP, respectively. In addition, increase in coronary vascular resistance was only 23 +/- 7% and 13 +/- 6% in anti-LFA-1 and anti-ICAM-1-treated groups, respectively. Values are significantly different between the control group and MAb-treated groups. Ischemia and reperfusion resulted in a 16% increase of myocardial tissue water content (3.71 +/- 0.03 in pre-ischemic baseline versus 4.29 +/- 0.08 ml/g dry weight) in the control group, whereas that resulted in only 3.0 and 5.7% increase in anti-LFA and anti-ICAM-1-treated groups, respectively. The difference between the control group and MAb-treated groups was significant. Cardiac energy status as assessed by adenosine triphosphate (ATP) concentration was markedly reduced in the control group at 40 min of reperfusion compared with pre-ischemic baseline values (5.70 +/- 0.27 vs. 14.92 +/- 0.48 mumol/g dry weight). In contrast, the reduction of myocardial ATP concentration at 40 min of reperfusion was significantly inhibited by anti-LFA-1 and anti-ICAM-1 monoclonal antibody treatment (5.70 +/- 0.27 vs. 8.96 +/- 0.52 and 8.10 +/- 0.47 mumol/g dry weight, respectively). These results suggest that a LFA-1/ICAM-1 pathway plays a critical role in the pathogenesis of postischemic myocardial injury during early reperfusion period.

Selective visceral and renal perfusion in thoracoabdominal aneurysm repair.

OBJECTIVE Whether or not selective visceral and renal perfusion during thoracoabdominal aortic aneurysm (TAAA) repair has a protective effect on visceral and renal function remains unknown. The aim of this study was to clarify if selective perfusion has such an effect. METHODS From May 1982 to December 1997, 82 consecutive patients underwent TAAA repair. Patients receiving hypothermic circulatory arrest or cooling of the kidney using Ringers lactate solution were excluded, thus 73 patients were enrolled into this study. They were divided into three groups: those in whom selective visceral and renal perfusion was performed using a roller pump (n = 41), those in whom it was performed using a centrifugal pump with a reduced heparin regimen (n = 22) and those who underwent simple aortic clamping alone (n = 10). RESULTS Serum creatinine, total bilirubin and alanine aminotransferase levels were elevated postoperatively in patients undergoing simple cross-clamp repair, but remained almost within normal limits in patients undergoing TAAA repair with selective visceral and renal perfusion. Urine output was more in selective perfused patients than in non-perfused patients. Renal dysfunction, defined by requirement of hemodialysis or by a serum level of creatinine above 3 mg/dl, occurred in four patients (10%) of the roller pump group and in two patients (9%) of the centrifugal pump group, while in four patients (40%) of the simple cross-clamping group. CONCLUSION Our experience suggests that selective visceral and renal perfusion has a protective effect on hepato-renal function during TAAA repair.

The elephant trunk technique for type A dissection.

Abstract A modified elephant trunk technique that was used to treat acute type A dissection is described. This technique prevents leaks at the distal anastomosis and facilitates surgery on the aneurysmatic downstream aorta following total arch replacement. In addition, it allows closure of the primary intimal tear in patients with DeBakey type III retrograde dissection.

Impending rupture of the descending aorta by enlargement of the false lumen after graft replacement with the elephant trunk technique: report of a case.

We report herein a case of an impending rupture of the descending aorta caused by an enlargement of the false lumen after a graft replacement using the elephant trunk technique. The patient was a 51-year-old woman who had received a graft replacement of the ascending aorta for an acute Stanford type A aortic dissection 6 years previously. An enhanced computed tomographic scan and digital subtraction angiography revealed pseudoaneurysms at the proximal and distal anastmotic site, and a residual dissection of the aortic arch. A graft replacement of the ascending aorta to the aortic arch was performed with the distal site using the elephant trunk technique. Five days after the operation, massive bleeding from the drainage tube occurred. A chest enhanced computed tomographic scan suggested an impending rupture of the descending aorta caused by an enlargement of the false lumen. A graft replacement of the descending aorta was carried out. Postoperatively she had no complications, and digital subtraction angiography showed an excellent reconstruction of the thoracic aorta. One month after the second operation, she was discharged from hospital.

Prevention of cardiac reperfusion injury following global ischemia by a monoclonal antibody, R2-1A6

The effect of R2-1A6 monoclonal antibody on the reperfusion injury of heterotopically transplanted rat cardiac tissues after global ischemia was studied. Histological, functional as well as myocardial energy status were evaluated in control and R2-1A6-treated rats. The strong binding of neutrophils to cardiac endothelial cell surface and strong tissue edema were present at 10 min after the initiation of reperfusion and subsequently interstitial hemorrhage and myocardial degeneration were present in the control group. The mean survival date of grafted hearts was about 7.7 days in the control group. In contrast, the significantly less severe binding of neutrophils to endothelial cells, tissue edema, interstitial hemorrhage, and myocardial degeneration were present in R2-1A6-treated rats. All grafted hearts survived up to 14 days in R2-1A6-treated group. Myocardial ATP content decreased from preischemic value of about 4 mumol/g to post-ischemic value of 0.57 mumol/g. After reperfusion of ischemic hearts, myocardial ATP values remained to be a range of 1.27-1.03 mumol/g in control group. However, myocardial ATP values recovered up to 2.28 mumol/g in R2-1A6-treated group. Thus, these experiments indicated that neutrophil adherence to endothelial cells is a critical early event in the process leading to post-ischemic reperfusion injury in global ischemia and the R2-1A6 treatment resulted in significant protection against cardiac reperfusion injury following global ischemia.

Internal Iliac Artery Aneurysmo–Colonic Fistula after Endovascular Stent-Graft Repair: A Case Report

We describe rare ilio-enteric fistula that developed after endovascular repair of a left internal iliac artery aneurysm (IIAA). An 83-year-old man with a history of previous surgeries via laparotomies suddenly developed a high fever 3 years after undergoing endovascular abdominal aortic repair (EVAR) with a stent-graft to treat a left isolated IIAA. Computed tomography imaging revealed a fistula between the IIAA and the sigmoid colon. A colostomy was created because severe intraperitoneal adhesions prevented resection of the IIAA. The postoperative course was uneventful and the patient remained free of infection without antibiotics. Residual aneurysms can cause complications after EVAR.

Enlargement of ulcer-like projections after repair of acute type A aortic dissection

We treated two cases of enlargement of ulcer-like projections in the descending thoracic aorta, which were recognized after emergency graft replacement from the ascending aorta to the aortic arch for acute type A aortic dissection. The intimal tear, which was near the left subclavian artery, was resected during the initial operation. Graft replacement of the descending thoracic aorta was successful.