[Effect of the size of abdominal aortic aneurysm on endovascular exclusion and its results].

OBJECTIVE: To evaluate the effect of the diameter of abdominal aortic aneurysm (AAA) on endovascular exclusion (EVE) and its results. METHODS: From March 1997 to June 2007, 429 AAA patients were treated with endovascular stent-graft exclusion. According to the maximal diameter of abdominal aortic aneurysm, the patients were divided into two groups: group A (diameter < 55 mm, n = 274) and group B (diameter > or = 55 mm, n = 155). The diameter of AAA, involvement of iliac artery, length, diameter and distortion of aneurismal neck in the two groups were recorded and compared retrospectively. RESULTS: Patients in group B were significantly older than group A (73.7 vs 71.1 years, P < 0.05). More patients in group B was complicated with coronary artery disease than those in group A (P < 0.05). The mean diameter of AAA in group A was (46.6 +/- 6.8) mm, and (66.8 +/- 11.2) mm in group B (P < 0.05). Proximal aneurysmal necks were shorter, wider and more tortuous in group B than those in group A (P < 0.05). Extraperitoneal approach, embolism of inner iliac artery and reconstruction of another inner iliac artery and stretch technique were more applied in group B. There were more endoleak during operation in group B and more stent-grafts were used. There was significant difference in morbidity rate between the two groups, while no statistic difference in mortality. And in group B, there were a high rate of endoleak and secondary intervention post operation. CONCLUSIONS: The diameter of AAA affects EVE and its results. In small aneurysms, EVE carries better outcome than in big aneurysms.

Simultaneous multi-tear exclusion: an optimal strategy for type B thoracic aortic dissection initially proved by a single center's 8 years experience.

BACKGROUND: Endovascular stent-grafting is widely used to treat thoracic aortic dissection. However, little information is available regarding outcome following simultaneous exclusion of multiple tears. This report details eight years of experience using simultaneous multi-tear exclusion for treatment of Stanford type B thoracic aortic dissection resulting in successful aortic remodeling without adverse events. METHODS: From September 1998 to January 2006, 29 type B thoracic aortic dissection patients (24 men, 5 women; 27 chronic, 2 acute; mean age 58 years, range 45 - 77 years) were treated by simultaneous multi-tear exclusion in our center. Magnetic resonance angiography was used as the preoperative evaluation method. Different kinds of stent-grafts were used. The patients were followed up with contrast-enhanced spiral computed tomography at 6 months postoperatively and yearly thereafter. RESULTS: Twenty-nine surgeries were completed successfully using at least 2 stent-grafts per patient (range: 2 - 6, mean: 2.7). No major procedure-related complications, such as rupture, paraplegia, aortic branch ischemia or cerebral infarction, were observed. During follow-up, favorable remodeling of the aorta was observed. CONCLUSIONS: The mid-term result of thoracic aortic dissection with simultaneous multi-tear exclusion was satisfactory. With the improvement of stent-grafts, simultaneous multi-tear exclusion should find wider application and become an optimal strategy for thoracic aortic dissection.

[Endovascular exclusion of juxtarenal abdominal aortic aneurysm with one-piece customized fenestrated endovascular stent-graft].

OBJECTIVE: To evaluate the technical feasibility of juxtarenal abdominal aortic aneurysm (AAA) repair with fenestrated endovascular stent-graft METHODS: A 64-year-old male was diagnosed with juxtarenal AAA with severe coronary artery stenosis, fenestrations was customized according to precise helical CT data to accommodate visceral and renal arteries. Under general anesthesia and dynamic supervision of digital subtraction angiography (DSA), juxtarenal AAA was excluded with the customized fenestrated stent-graft and balloon expandable mini stent-grafts were deployed into bilateral renal arteries respectively. RESULTS: After operation, DSA showed the patency of the super mesenteric artery, bilateral renal arteries and left hypogastric artery, no endoleak was found. The serum creatinine decreased slightly after operation. CT angiography revealed favorable morphology of the stent-graft without tortuosity, migration, disjoint and endoleak 10 days after the operation and patency of super mesenteric artery, bilateral renal arteries and left hypogastric artery. CONCLUSIONS: The placement of customized fenestrated endovascular stent-graft is a feasible option for juxtarenal AAA.

Role of nitric oxide and inducible nitric oxide synthase in human abdominal aortic aneurysms: a preliminary study.

BACKGROUND: Nitric oxide (NO) is an important mediator in the pathophysiology of many vascular diseases. However, the definite role of NO in human abdominal aortic aneurysm (AAA) formation is unclear. The aim of this study was to investigate production of NO and expression of inducible nitric oxide synthase (iNOS), and their possible role in AAA. METHODS: A total of 28 patients with AAA, 10 healthy controls, and 8 patients with arterial occlusive disease were enrolled into this study. Standard colorimetric assay was used to examine NO concentration in plasma from patients with AAA and normal controls, and in cultured smooth muscle cells (SMCs). Expression of iNOS in aortas and cultured SMCs were detected by immunochemistry. The correlation of iNOS expression with age of the patient, size of aneurysm, and degree of inflammation was also investigated by Cochran-Mantel-Haenszel chi2 test and Kendall' Tau correlation. RESULTS: Expression of iNOS increased significantly in the wall of aneurism in the patients with AAA compared to the healthy controls (P < 0.05) and the patients with occlusive arteries (P < 0.05). iNOS protein and media NOx (nitrite + nitrate) also increased in cultured SMCs from human AAA (n = 4, P < 0.05), while plasma NOx decreased in patients with AAA (n = 25) compared to the healthy controls (n = 20). There was a positive correlation between iNOS protein and degree of inflammation in aneurismal wall (Kendall coefficient = 0.5032, P = 0.0029). CONCLUSIONS: SMCs and inflammatory cells were main cellular sources of increased iNOS in AAA, and NO may play a part in pathogenesis in AAA through inflammation.