Open surgery or stent repair for descending aortic diseases: Results and risk factor analysis.

OBJECTIVES: Less invasive stent graft (SG) repair was compared with open surgery for patients with descending thoracic aortic diseases. DESIGN: Thirty six patients undergoing SG repair (SG group) were matched for age, sex, location and pathology of aortic disease with a 36-patient surgical cohort (OS group), and retrospective matched case-control study was performed with respect to outcomes and risk factors for adverse outcomes. RESULTS: Mortality rate was 5.6% in OS group and none in SG group (p=0.4930), and there was no significant difference in stroke and paraplegia rates between two groups. A higher prevalence of secondary procedures due to endoleak was seen in the patients of SG group (p=0.0113). Perioperative hypotension was an independent risk factor for in-hospital mortality (p=0.0071, odds ratio=34) and preoperative renal dysfunction was independent risk factor for paraplegia (p=0.0076, odds ratio=17.6). CONCLUSIONS: Although the importance of patient selection is emphasized to prevent endoleak, mortality rate was low in patients who underwent SG repair. SG repair is a promising alternative technique to open surgery for thoracic aortic diseases.

Adventitial mast cells contribute to pathogenesis in the progression of abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) is histologically characterized by medial degeneration and various degrees of chronic adventitial inflammation, although the mechanisms for progression of aneurysm are poorly understood. In the present study, we carried out histological study of AAA tissues of patients, and interventional animal and cell culture experiments to investigate a role of mast cells in the pathogenesis of AAA. The number of mast cells was found to increase in the outer media or adventitia of human AAA, showing a positive correlation between the cell number and the AAA diameter. Aneurysmal dilatation of the aorta was seen in the control (+/+) rats following periaortic application of calcium chloride (CaCl2) treatment but not in the mast cell-deficient mutant Ws/Ws rats. The AAA formation was accompanied by accumulation of mast cells, T lymphocytes and by activated matrix metalloproteinase 9, reduced elastin levels and augmented angiogenesis in the aortic tissue, but these changes were much less in the Ws/Ws rats than in the controls. Similarly, mast cells were accumulated and activated at the adventitia of aneurysmal aorta in the apolipoprotein E-deficient mice. The pharmacological intervention with the tranilast, an inhibitor of mast cell degranulation, attenuated AAA development in these rodent models. In the cell culture experiment, a mast cell directly augmented matrix metalloproteinase 9 activity produced by the monocyte/macrophage. Collectively, these data suggest that adventitial mast cells play a critical role in the progression of AAA.

[Complete resection of the invasive thymoma combined with replacement of aortic arch and pneumonectomy].

A 68-year-old male was found an abnormal shadow on chest X-ray and was diagnosed as thymoma by computed tomography (CT)-guided needle biopsy. As the tumor invaded the aortic arch, left main pulmonary artery and the lung, thymectomy combined resection of the surrounding tissues was performed for the complete resection. The aortic arch was replaced with cardiovascular graft under cardiopulmonary bypass, with the aid of selective cerebral perfusion. The left pneumonectomy was performed because the tumor invaded to the left main pulmonary artery and to the lung parenchyma. Masaoka stage III and histologic type B2 were diagnosed according to the World Health Organization classification. The patient has been well without recurrence or metastasis after the surgery for 2 years. A complete resection of the thymoma invaded to great vessels should be performed to expect for the good curability and prognosis.

Clinical analysis of acute type A intramural hematoma: comparison between two different pathophysiological types.

BACKGROUND: Type A intramural hematoma (IMH) has two different etiologies, which are rupture of vasa vasorum and penetrating atherosclerotic ulcer (PAU); however, it is difficult to know which is the initiating event. METHODS: Between January 1993 and August 2004, 28 patients of acute type A IMH were treated in our department and were divided into two groups, 20 patients with IMH probably caused by rupture of vasa vasorum (non-PAU group) and 8 patients with IMH probably caused by PAU (PAU group), according to pathologic specimen and atherosclerotic findings on computed tomography. Background factors, radiographic findings, and prognosis were analyzed retrospectively. RESULTS: Surgery was performed in 15 patients (75%) in non-PAU group and 4 patients (50%) in PAU group during the first admission. Late progression was noted in 3 patients, and operation was required. Finally, operation was performed in 22 patients (78.6%). The history of myocardial infarction (p = 0.026) and chronic renal failure (p = 0.026) were more associated with PAU group than with non-PAU group. Ascending aortic diameter at the onset was significantly larger in non-PAU group (50.3 +/- 6.6 mm) than in PAU group (43.9 +/- 9.0 mm; p = 0.046), and there were significantly more ulcer lesions in PAU group (1.9 +/- 0.4) than in non-PAU group (1.1 +/- 0.4; p = 0.0004). There was no significant difference in long-term survival rates between them. CONCLUSIONS: The PAU group patients have more coexisting atherosclerotic diseases and multiple aortic ulcer lesions with significantly mild ascending aortic dilatation compared with non-PAU group patients.

Predictor of neurologic dysfunction after elective thoracic aorta repair using selective cerebral perfusion.

OBJECTIVES: This study was undertaken to determine the factors that influence postoperative neurological dysfunction after selective cerebral perfusion (SCP). DESIGN: From 1995 to August 2004, 60 patients were evaluated for the presence of cerebro-vascular disease (CVD), and then underwent thoracic aortic operations using SCP. Perioperative factors were evaluated by multivariate analyses. RESULTS: Hospital mortality rate was zero. Sixteen patients (26.7%) proved to have CVD. Permanent neurological dysfunction (PND) appeared in three patients (5.0%) and transient neurological dysfunction (TND) in two (3.3%). Univariate analysis revealed superficial temporal artery (STA) pressure during SCP (p = 0.0410) to be a significant risk factor for PND. Variables that achieved values of p < 0.2 (aortic cross-clamp time, presence of CVD, old cerebral infarction, presence of clots or atheroma) were examined with multivariate analysis and the presence of CVD (p = 0.038) and STA pressure during SCP (p = 0.032) were independent risk factors for PND. Multivariate analysis for TND did not show any risk factor. CONCLUSIONS: The presence of CVD was indicated as an independent risk factor for PND after thoracic aortic operations using SCP.

Selective delayed management of blunt traumatic left common carotid artery injury using hypothermic circulatory arrest.

Most traumatic carotid artery aneurysms occur at or close to its bifurcation, and traumatic aneurysm of the intrathoracic carotid arteries are rare. We describe a case of false aneurysm at the origin of the left common carotid artery (LCCA) after blunt trauma. A 53-year-old man suffered a blow from a broken steel plate, which flew from a working concrete crusher over his neck when he looked down the machine. Chest computed tomography revealed aneurysm of the LCCA, and aortic arch arteriography demonstrated a false aneurysm of about 3 x 5 cm at the origin of the LCCA, with loss of arterial continuity and abnormal tortuosity above the aneurysm. An ascending aorta to LCCA bypass graft was placed during the cooling period of cardiopulmonary bypass, and mattress sutures were placed in the normal aorta to close the origin of the LCCA under hypothermic circulatory arrest because of the extreme danger of dissection. The LCCA was transected partially at its origin from the aorta. We speculated that the direct lifting force which caused the carotid artery to move upward might produce a tear at the junction of the LCCA and the aortic arch.

Surgical resection of right atrial neurilemoma extending to pulmonary vein.

An asymptomatic cardiac neurilemoma was found in a 33-year-old woman. The tumor was on the anterior surface of the right atrium extending to the right upper pulmonary vein across the interatrial groove. The tumor was resected completely and right atrium, interatrial septum, left atrium and right superior pulmonary vein were reconstructed with cardiopulmonary bypass. The patient recovered uneventfully and had no recurrence 1 year after the operation. We reviewed ten reported cases of cardiac neurilemoma, including our patient.

Influence of heparin dosage on hemostasis under combined use of Nafamostat mesilate during deep hypothermic circulatory arrest.

OBJECTIVE: Nafamostat mesilate (NM) is a guanidine acid derivative which is synthesized in Japan as an antifibrinolytic drug. It has been successfully used to decrease blood loss and blood product requirement in cardiac operations. As there have been some reports that insufficient heparinization might induce the coagulopathic state in aprotinin-treated patients undergoing deep hypothermia and circulatory arrest (DHCA), we have reviewed 16 consecutive patients who underwent total aortic arch replacement using DHCA and the associated use of NM. METHODS: The patients were divided into two groups; a Normal-dosage Group (n = 8) who received 3 mg/kg of heparin, and a Low-dosage Group (n = 8) who received 1.5 mg/kg of heparin. The Celite-activating clotting time was maintained at longer than 1,000 seconds in both groups. Blood loss, transfusion requirements and the volume of postoperative mediastinal tube drainage were compared between the two groups. RESULTS: We observed no adverse effects of NM and no significant difference in transfusion requirements between both groups. There was a significant difference in blood loss during the operation between the two groups (p < 0.05) (Low-dosage Group 1,973 +/- 959 ml vs Normal-dosage Group 1,059 +/- 704 ml). CONCLUSIONS: NM was a safe antifibrinolytic drug. Adequate heparinization was necessary to reduce hemorrhage in patients undergoing aortic arch replacement using DHCA and the associated use of NM.

Acetabular labrum entrapment following traumatic posterior dislocation of the hip.

In traumatic dislocation of the hip with or without a fracture of the acetabular rim, complete anatomical reduction might be prevented by a bone fragment or infrequently by a soft tissue block, such as a torn acetabular labrum, ruptured capsule, or round ligament. We report a rare case of a tear in the acetabular labrum that prevented complete reduction of the dislocated hip. A 26-year-old man suffered posterior dislocation of the right hip, which was reduced under general anesthesia. The postreduction radiograph showed that the reduction was not complete, and a thin bony fragment was observed in the joint space in the weight-bearing area. Open reduction was performed 11 days later. We found a free bone fragment in the joint space, which was removed. The postoperative radiograph still did not show complete reduction of the hip. A large defect in the contrast medium was shown in the widened joint space by arthrography, which revealed the existence of the soft tissue interposition. We then performed a second operation and learned that the acetabular labrum was widely detached from the anterior to the posterior acetabular rim and was lying deep within the acetabulum. This detached portion of the labrum was excised, and the hip was reduced. The radiograph obtained during surgery then showed complete, concentric reduction. We missed the diagnosis clinically and radiologically at the first operation, proving how important it is to obtain an accurate radiological diagnosis in the operating room.

Study in three different types of cardiopulmonary bypass on arterial ketone body ratio: its prognostic implication and participation of body temperature.

The aim of this study was to investigate the change of hepatic metabolic activity presented by the ketone body ratio (AKBR) during and after cardiopulmonary bypass (CPB) and to evaluate the prognostic value. AKBR were measured in 20 cases of coronary aortic bypass grafting using moderate hypothermic CPB (group M), ten cases of aortic arch surgery using deep hypothermia with selective cerebral perfusion (DHSCP) with an open technique (group D) and 15 cases of descending thoracic aortic replacement using partial CPB (group N). AKBR decreased significantly in all groups 5 min after CPB compared with the value before CPB. There was a significant difference in AKBR 1 h after CPB among the three groups and AKBR returned to the prebypass value in group N (group M, 0.32 +/- 0.16; group D, 0.14 +/- 0.04; group N, 0.48 +/- 0.14; P < 0.0001). AKBR rose significantly after the discontinuation of CPB compared with the value during CPB and returned to the prebypass value in groups M and D. The patients who underwent DHSCP with an open technique had a value of AKBR below 0.2, but liver function still recovered normally. The value of AKBR correlated with temperature significantly and a very low level of AKBR below 0.2 was observed during core cooling to 20 degrees C without negative prognostic implications. AKBR decreased 5 min after CPB in group N which suggested decreased hepatic perfusion at an early stage of partial CPB. The prognostic implication of AKBR during CPB is whether low level AKBR recovers or not.