[Spontaneous rupture of the thoracic aorta diagnosed rupture of the acute stanford type B aortic dissection at preoperation; report of a case].

BACKGROUND: Spontaneous rupture of the thoracic aorta is extremely rare. It is very difficult to diagnose it preoperatively. CASE: A 71-year-old woman suffered the sudden onset of severe chest and back pain and was admitted to our hospital. Enhanced computed tomography (CT) showed mediastinal hematoma and apparent aortic dissection in the aortic arch and descending aorta. We diagnosed the rupture of Stanford type B dissection and performed an emergency operation. 20 mm tear was found in the intima of lesser curvature of aortic arch and 5 mm perforation was found in the adventitia of this part. There was no flap or false lumen suggestive of a dissection nor was there aortic aneurysm. Total aortic arch replacement was performed. RESULT: The surgery was followed by an uneventful postoperative course. CONCLUSION: A case of spontaneous rupture of the thoracic aorta which was diagnosed the rupture of Stanford type B dissection preoperatively was successfully treated.

[Thoracic aortic dissection complicating autosomal dominant polycystic kidney disease; report of a case].

A 55-year-old man underwent aortic valve replacement for aortic valve insufficiency 12 years ago. At that time, autosomal dominant polycystic kidney disease was diagnosed. Subsequently, renal failure developed gradually. In August 2007, the patient was admitted to the hospital because of dull back pain. Computed tomography (CT) revealed aortic dissection extending from the ascending aorta to the bifurcation of the iliac artery (Stanford type A). However, the patient had no severe symptoms associated with aortic dissection On the basis of the results of CT and blood testing, chronic aortic dissection was diagnosed. Because the patient also had chronic renal failure we decided to perform elective surgery. In January 2008, ascending aortic and aortic arch replacement with a distal elephant trunk was performed. After surgery, we were concerned about the risk of renal failure. However, the patient recovered uneventfully, without requiring dialysis. Aortic dissection can occur as a complication in patients with autosomal dominant polycystic kidney. Strict control of blood pressure is therefore essential in such patients.

Clinical long-term results of vascular prosthesis sealed with fragmented autologous adipose tissue.

Tissue engineering can improve the former limitations of artificial organs. This article reports the long-term clinical results of grafts constructed with fragmented autologous adipose tissue. We did a retrospective analysis of a series of 53 patients with lower leg ischemia that received 69 fragmented adipose tissue (FAT) grafts implantation at our institution. The mean follow-up period was 36.0 months. After 1, 2, 3, and 5 years, the primary potency rates were 85.3, 83.3, 73.8, and 67.7%, respectively. The lumen of occluded areas not only at anastomotic sites but also in areas far from the anastomotic sites was occupied by a thickened neointima, which had a great number of capillary blood vessels, elastic laminae, smooth muscle cells, fibroblasts, and collagen fibers. This type of intimal hyperplasia was a characteristic finding in the FAT grafts. From the results of this clinical trial, we conclude that the FAT grafts are acceptable as vascular prostheses for ischemic lower extremities. The intimal hyperplasia at sites far from the anastomotic lines suggested the possibility of neointima formation throughout the luminal surface of the grafts.

Midterm results of stent-graft repair for thoracic aortic aneurysms: computed tomographic evaluation.

Midterm observation of endovascular surgery using a fabric-covered stent graft for thoracic aortic aneurysms is discussed with postoperative follow-up findings based on regularly performed thoracic computed tomography (CT). From 1996 to 1999, 20 patients with thoracic aortic aneurysm underwent stent-graft placement in our hospital. One year follow-up CT results after placement were obtained for 17 patients. The CT scans found that there were both thrombosis and size reduction of aneurysm in 8 patients (46%), thrombosis without size reduction in 2 (13%), a new ulcerlike projection (ULP) in 3 (19%), persistent minor endoleakage in 2 (13%), a new endoleak in 1 (6%), and a recurrent endoleak from intercostal arteries in 1 (6%). The new ULP formation seemed to be a peculiar problem stemming from an intimal injury caused by edges of the stent. Therefore, we recently adopted a new spiral stent instead of the previous stent to avoid the injury. The new endoleak suggested that aneurysmal thrombosis without size reduction could cause the aneurysm to develop recurrent endoleaks. From these findings, we concluded that midterm observation of stent-graft repair for thoracic aortic aneurysms did not give satisfactory results. In order to improve the results of endovascular surgery using stent-grafts, we need to develop safer stent grafts with a reliable design to prevent endoleaks and to avoid intimal injury of the aorta. We also hope to develop effective technologies that can accelerate organization of thrombus in the aortic aneurysm after stent-graft placement.

[Continuous monitoring of hepatic venous oxygen saturation (SHVO2) as a new diagnostic indicator of abdominal malperfusion in acute aortic dissection].

A 73-year-old woman was admitted with sudden-onset back and abdominal pain. Computed tomography scanning revealed type B acute aortic dissection with narrowing of the true lumen. We inserted an oximetric catheter into the right hepatic vein and started continuous measurement of ShvO2. The initial value was 20%. Consecutive aortograms showed an intimal tear in the thoracic descending aorta. Endovascular stent graft placement was performed to close the entry, and ShvO2 rose to more than 60% immediately after the stent graft expansion. ShvO2 is an excellent indicator of abdominal blood flow, not only for early diagnosis but also for the evaluation of treatment.

Measurement of cytokine levels by coronary sinus blood sampling during cardiac surgery with cardiopulmonary bypass.

Interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase levels in coronary sinus blood were measured and compared with those in arterial blood drawn from the radial artery before and immediately after cardiopulmonary bypass (CPB) during coronary artery bypass grafting in 20 patients. We introduced coronary sinus blood sampling as a useful method for evaluation of myocardial metabolism, myocardial protection, and reperfusion injury during CPB, especially by measurement of cytokines. Because interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase are inflammatory mediators, we speculated that they might show higher levels in coronary sinus blood than in systemic arterial blood. The results obtained from the 20 patients showed that levels of interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase increased immediately after CPB (p < .01), but there was no significant difference in these levels between coronary sinus and systemic arterial blood. We conclude that the myocardium is not a predominant source of their release during CPB. Our results also showed that the measurement of these cytokines in systemic arterial blood reflected their levels in the whole body, including the myocardium, even during cardiac operation with CPB.

Percutaneous insertion of a jacketed stent to close the entry of dissecting aortic aneurysms of DeBakey types I and II.

As a treatment for dissecting aortic aneurysms of DeBakey Types I and II, a percutaneous insertion method using a new jacketed stent was developed. The efficacy of the method was evaluated in an animal study. We developed a special stent prepared by modifying the original Gianturco self-expandable metallic stent and a fabric patch. A model of a dissecting aortic aneurysm of DeBakey Type I was created in dogs. The device was inserted into the ascending aorta from the left carotid artery through a sheath-introducer system. The aortogram showed the bloodstream through the false lumen before the insertion, but no bloodstream after the stent insertion. The autopsy showed that the entry, the reentry, and the false lumen were completely filled with fresh thrombus. By using this stent, we successfully achieved an interventional treatment for dissecting aortic aneurysms of DeBakey Types I and II.