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N Shiiya

Publications and source records attributed to N Shiiya.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Early and long-term results of surgery for aortic arch aneurysms using selective cerebral perfusion].

OBJECTIVE: We report our operative technique for atherosclerotic arch aneurysms and early and long term results of the surgery. METHODS: Between April 1992 and December 2001, 80 consecutive patients underwent operation for atherosclerotic arch aneurysms. Their mean age was 70 +/- 7 years. Sixty-six (82.5%) patients were operated on electively. All operations were performed under median sternotomy using hypothermic circulatory arrest and selective antegrade cerebral perfusion. Total arch replacement was performed in 66 cases, proximal hemiarch replacement in 4 cases, distal arch replacement using stent graft implantation via aortic arch incision in 8 cases, and patch angioplasty in 2 cases. In 9 of these patients in whom mobile arch atheroma was revealed by intraoperative epiaortic ultrasonography, isolation technique was employed to avoid embolic stroke. RESULTS: Overall in-hospital mortality was 10.0% (8 of 80 patients). Postoperative temporary neurologic dysfunction was 7.5%, and stroke rate was 5.0%. The 3-year, and 5-year actuarial survival rate including hospital death was 79.3% and 75.3% respectively. The 3-year, and 5-year cardiovascular event free survival rate was 68.3% and 60.0% respectively. CONCLUSION: The early and long-term results of surgery for atherosclerotic arch aneurysms were acceptable. Selective cerebral perfusion is an effective brain protective adjunct.

Aged↗
PubMed2002

[An evaluation of the potential ischemia of the forearm after harvesting of radial artery by near infrared spectroscopy].

We evaluated the potential ischemia of the forearm after harvesting of radial artery (RA) for coronary artery bypass grafting (CABG) by near infrared spectroscopy (NIRS). The subjects consist of two groups; patients group (group P) including 18 patients who received CABG with RA and control group (group C) including 9 healthy volunteers. Group P was divided into two groups; early post operative group (group E, n = 11) and mid-term post operative group (group M, n = 7). NIRS was used to measure the recovery time (RT) in the muscles of the forearm during occlusion test. There was a significant prolongation of the RT in group P than group C. There was no significant difference of the RT between group E and group M. In conclusion, harvesting of RA may cause ischemia of the forearm and it may continue for a long time.

Aged↗
PubMed2002

[Surgical results for aortic involvement in Marfan syndrome].

From 1991 through 2001, 21 Marfan patients underwent aortic operations in our hospital. They received a total of 36 aortic operations, 31 by ourselves including 4 non-elective operations and 2 operations before 1991. Extent of replacement was Bentall + total arch (4), Bentall (8), valve sparing aortic root (reimplantation) (2), re-anastomosis + coronary aortic bypass grafting (CABG) after Bentall (1), ascending + total arch (3), ascending (1), total arch (1), total thoracoabdominal (10), thoracoabdominal (1), descending thoracic (2), distal arch (1), abdominal (2). Multiple operations were required in 11 patients (2 operations in 7, 3 operations in 4). Eight reoperations in 6 patients were for adjacent lesion, 5 reoperations were for remote lesion, and 2 others were for complication of Bentall (initial operation elsewhere). Among the 8 reoperations for adjacent lesion, 3 were scheduled operation (2 with elephant trunk), 4 were for residual dissection, and 1 was for annulo-aortic ectasia (AAE). Total aortic replacement was achieved in 4 and subtotal replacement excluding the root in 2. There was no hospital mortality. Paraparesis occurred in 1 who died 4.7 years after operation. The remaining patients are currently alive. No other aortic event occurred. Aortic reoperation-free survival was 83% at 5 year and 28% at 10 year.

Adolescent↗
PubMed2001

Thymic carcinoma with tumor thrombus into the superior vena cava.

Tumor thrombus into the vena cava have been reported in cases with renal cell carcinoma, thyroid tumor and in those with thymoma. These tumors are frequently invasive and continuous from the main tumor that shows direct vessel wall invasion. Here, we report a case of thymic carcinoma with superior vena cava syndrome, which was caused by a tumor thrombus in the superior vena cava without vessel wall invasion. The main mediastinal tumor did not show innominate vein invasion, and the superior vena cava syndrome was a result of separate tumor thrombus that was free of vessel wall invasion. The tumor thrombus could be removed through a simple venotomy. To prevent stenosis in the superior vena cava and the left innominate vein, we used a pericardial patch to close the venotomy site.

Carcinoma, Renal Cell↗
PubMed2001

Proinflammatory cytokines in cerebrospinal fluid in repair of thoracoabdominal aorta.

BACKGROUND: Little is known about alterations of cytokine levels in cerebrospinal fluid (CSF) during thoracoabdominal aortic surgery. We measured perioperative CSF cytokine levels to determine their clinical significances. METHODS: Perioperative serum and CSF levels of cytokine were measured in 15 adult patients undergoing repair of the descending thoracic aorta (n = 4) or thoracoabdominal aorta (n = 11). All patients underwent prosthetic replacement and perioperative CSF drainage. Serum and CSF levels of tumor necrosis factor-alpha, Interleukin- (IL-) 1beta, IL-6, IL-8, IL-10, and IL-12 were measured before operation and at 0, 6, 12, 18, 24, 48, and 72 hours postoperatively using enzyme-linked immunosorbent assays. RESULTS: There were no hospital deaths, but 1 patient suffered paraplegia. Cerebrospinal fluid IL-8 levels peaked at immediately after operation (751.7 +/- 42.1 pg/mL versus preoperative levels, 54.9 +/- 24.6 pg/mL; p < 0.001), and the higher levels persisted for 72 hours. In contrast, serum IL-8 levels did not change and remained lower than CSF levels. The patient with paraplegia had the highest CSF IL-8 levels throughout the study period. Serum and CSF levels of tumor necrosis factor-alpha, IL-1beta, IL-6, and IL-12 did not significantly change. Serum and CSF levels of IL-10 were significantly elevated after operation compared with preoperative levels. In contrast to IL-8, serum IL-10 levels surpassed CSF levels. CONCLUSIONS: Cerebrospinal fluid IL-8 levels are significantly elevated in thoracoabdominal aortic operation, and may be the most sensitive to the inflammatory response in the ischemic spinal cord injury. Persistent elevation of CSF IL-8 levels may be predictive of further development of neurologic deficits, and a reduction of proinflammatory cytokine levels may be a beneficial effect of CSF drainage, but this requires further investigation.

Adult↗
PubMed2001

Isolation technique for stroke prevention in patients with a mobile atheroma.

Mobile atheroma in the proximal aorta is a risk factor for brain complication after cardiovascular operation. We report a new technique of replacing the ascending and transverse aorta by establishing selective hypothermic antegrade cerebral perfusion. After cooling, cerebral vessels are clamped and systemic perfusion is started. This technique was applied in 5 patients. All patients woke up normally and recovered without neurologic complication.

Aged↗
PubMed2001

Is preservation of the aortic valve different between acute and chronic type A aortic dissections?

OBJECTIVES: In repair of acute type A aortic dissection, the type of proximal repair of the ascending aorta has been of great interest; however, very few reports are available regarding this issue in chronic aortic dissection. The surgical strategies for proximal repair in chronic dissection may not the same as those for acute dissection. We reviewed our 10-year experience of both acute and chronic type A aortic dissections in order to elucidate the validity of valve preservation and the long-term results of aortic regurgitation (AR). METHODS: From 1990 to 1999, 93 patients (55 acute and 38 chronic dissections) underwent operation for type A aortic dissection. Five Marfan patients were included in each group. The degree of AR was evaluated by echocardiography before and after (at hospital discharge and late follow-up) operation. RESULTS: In acute type A aortic dissection (n=55), 16 patients had AR grade II or greater (29%), of whom seven had AR grade III (13%). In 29 patients, dissection was found below the sinotubular junction (STJ) and 14 patients had AR grade II or greater (48%). The aortic valve was replaced in four patients (7%), of whom three had Marfan's syndrome. Only one non-Marfan patient required aortic valve replacement because of valve stenosis. In those whose aortic valve was preserved (n=51), three patients still had AR grade II at hospital discharge, while at late follow-up, AR had deteriorated to grade III in two of them, although no reoperation has been required so far. In chronic type A aortic dissection (n=38), 14 patients had AR grade II or greater (37%), of whom 11 had AR grade III or greater (29% vs. 13% in acute dissection; P=0.051). In 15 patients, dissection was found below the STJ and 12 patients had AR grade II or greater (80% vs. 48% in acute dissection; P=0.043). The aortic valve was replaced in eight patients (21% vs. 7% in acute dissection; P=0.051), including three Marfan patients. Of those whose aortic valve was preserved (n=30), two patients required reoperation for severe AR. The freedom from postoperative AR grade III or greater was 89% at 5 years for operative survivors with acute dissection and 92% for those with chronic dissection, respectively. CONCLUSIONS: This retrospective study suggests that preservation of the aortic valve in acute type A aortic dissection is feasible in non-Marfan patients regardless of the degree of AR. In chronic dissection, aortic root replacement needs to be considered when the degree of AR is greater than moderate because of a dilated STJ and/or annulus. In both acute and chronic dissections, satisfactory mid- to long-term results with a low incidence of reoperation were obtained in those whose aortic valve was preserved.

Acute Disease↗
PubMed2001

The adenosine triphosphate-sensitive potassium channel opener nicorandil protects the ischemic rabbit spinal cord.

OBJECTIVE: We investigated the protective effects of an adenosine triphosphate-sensitive potassium channel opener nicorandil in the rabbit model of spinal cord ischemia. METHODS: Rabbits were randomized into 4 groups (each n = 6): the nicorandil group (100 microg/kg intravenous nicorandil 10 minutes before ischemia); the glibenclamide plus nicorandil group (3 mg/kg intravenous glibenclamide, an antagonist of adenosine triphosphate-sensitive potassium channels, 10 minutes before nicorandil administration); the vehicle group (vehicle alone); and the sham operation group (without spinal cord ischemia). Spinal cord ischemia was induced by balloon occlusion of the infrarenal abdominal aorta for 15 minutes at 39 degrees C. Neurologic function was graded into Johnson's score at 8 hours, 1 day, and 2 days. Histopathologic examination was performed at 2 days, and the number of intact motor neuron cells was compared. RESULTS: Johnson scores of the glibenclamide plus nicorandil and vehicle groups were significantly lower than those of the sham operation and nicorandil groups at each time point, and no statistically significant difference was observed between the glibenclamide plus nicorandil and vehicle groups. Histopathologic examination revealed that motor neurons were almost normal in the nicorandil group, whereas about 55% of motor neurons were lost in the vehicle and glibenclamide plus nicorandil groups. CONCLUSIONS: Nicorandil has a protective effect on the ischemic rabbit spinal cord, and the beneficial effect seems mediated through the activation of adenosine triphosphate-sensitive potassium channels.

Animals↗
PubMed2001

[Efficacy of additional Dor approach to coronary bypass grafting in severe left ventricular dysfunction with large akinetic area].

Between January 1994 and August 1999, we experienced 16 cases of coronary artery bypass grafting (CABG) in severe left ventricular dysfunction with left ventricular ejection fraction (LVEF) < or = 40%. Four had additional endoventricular patch plasty in large postinfarction akinetic scars, the so-called Dor approach, to CABG (group D). Eleven had only CABG, or CABG and mitral annuloplasty (group C). One had linear repair after the resection of the left ventricular aneurysm. One died of sustained low output syndrome 5 months after the operation in group C. Fractioning shortening and left ventricular diastolic diameter were not changed after the operation in group C. On the other hand, in group D, there were no complications after the operation, LVEF was significantly improved from 31.5 +/- 4.9% to 62.5 +/- 5.9% (p < 0.01) and the left ventricular end-diastolic volume index was reduced from 118 +/- 23 ml/m2 to 74 +/- 12 ml/m2 (p < 0.01). The Dor approach is considered to be a safe and effective additional procedure to CABG in severe patients with a large akinetic antero-septal segment.

Aged↗
PubMed2001

[Single-staged operation for the patients with concomitant diseases of coronary and carotid arteries].

The authors describe four cases with concomitant coronary and carotid severe stenosis operated by combined procedure. As the cerebral revascularization, carotid endarterectomy (CEA) was performed for three patients, while carotid artery bypass grafting was performed for the other one. In one patient with bilateral carotid stenosis, percutaneous transluminal stenting of the right internal carotid artery was performed one day before combined left CEA and coronary artery bypass grafting (CABG). Both perioperative myocardial infarction and neurological complication could be avoided in each case. When a CABG candidate also has significant extracranial carotid stenosis with clinical symptoms, combined cerebral revascularization and CABG is desirable.

Aged↗
PubMed2001

[Grafting and concomitant left ventricular myotomy-myectomy in a patient with coronary artery disease associated with hypertrophic obstructive cardiomyopathy].

A 44-year-old man complained of chest oppression and systolic murmur. Echocardiography showed subaortic stenosis with outflow gradient of 135 mmHg, interventricular septal thickness of 21 mm, left ventricular posterior wall thickness of 11 mm, and 2/4 mitral regurgitation. Selective coronary angiography demonstrated 75% stenosis in left anterior desending branch. Coronary artery revasculization comcomitant with left ventricular myotomy-myectomy was performed. He had a good recovery from operation, and was discharged in 19th days in NYHA class I. Echocardiography one month after operation showed mild outflow pressure gradient, light systolic anterior motion of mitral anterior leaflet, and 1/4 mitral regurgitation. Careful operative management, including myocardial protection, avoiding perporation of ventricular septum, and postoperative medical care are mandatory to this group of patients. The use of cathecholamine and Ca-blocker will be attentioned because of the increasing the left ventricular pressure gradient.

Adult↗
PubMed2001

Preoperative disseminated intravascular coagulation associated with aortic aneurysms.

BACKGROUND: To report clinical experiences with disseminated intravascular coagulation (DIC) associated with aortic aneurysms (AA) and discuss therapeutic strategy. METHODS DESIGN AND SETTINGS: uncontrolled, observational study in a university hospital. PATIENTS: among 547 patients with AA treated between 1991 and 1999, 10 patients (7 males, 3 females, mean age 68.5+/-2.5) presenting a preoperative DIC score (defined by the Ministry of Health and Welfare in Japan) of 6 or higher were analyzed. The etiology was dissection for 5 and non-dissection for 5 patients. Six of 10 patients had a bleeding tendency. Eight patients received preoperative anticoagulant therapy. Prosthetic replacement was undertaken for 8 patients except for 2 patients in poor condition. RESULTS: There were no operative deaths in 8 surgical cases. One non-surgical case died of deteriorated bleeding tendency. The mean DIC score was 8.0+/-0.6 at admission, which was reduced to 4.4+/-0.5 at discharge (p<0.05). Prothrombin time, platelet counts, and fibrinogen levels tended to be normalized by the 7th postoperative day. Serum FDP levels decreased with surgery, but tended to increase at the time of discharge and the later follow-up period. Hematologic disturbances and bleeding tendency recurred in 2 patients in the follow-up period. CONCLUSIONS: In the majority of patients presenting DIC with aortic aneurysm, surgical treatment can be performed safely if adequately managed by anticoagulant therapy. Consumptive coagulopathy usually resolved after surgical intervention, but some patients developed DIC in the later period. If DIC recurs, it is essential to search for contributory causes.

Aged↗
PubMed2001

A case of intraoperative acute aortic dissection caused by cannulation into an axillary artery.

Severe atherosclerotic disease of the ascending aorta is one of the risk factors of dissection of the ascending aorta and cerebral embolism during cardiac operations with cardiopulmonary bypass. Aortic dissection is rare, but once it happens, the mortality rate is high. For the patient with severely atherosclerotic or strongly calcified aorta, we should avoid cannulation into the aorta or clamping of it. In this case, we experienced aortic dissection although we chose the arterial cannulations into the axillary arteries because of the strong calcification of the ascending aorta and the abdominal aorta. The dissection was caused by the cannulation into the axillary artery. Transesophageal echocardiography (TEE) showed the dissection during the operation and the ascending aorta was replaced soon. Early diagnosis and treatment saved the patient. This case showed the following points: 1) cannulation into an axillary artery is not always safe; 2) TEE is very useful to detect the complicated dissection during operation; 3) replacement of the ascending aorta alone can be one of the choices for the treatment of aortic dissection caused by cannulation into an axillary artery.

Aged↗
PubMed2001

A case of an ascending aortic aneurysm due to mesoaortitis complicated with idiopathic thrombocytopenic purpura.

An 80-year-old man was referred to our hospital for the surgical treatment of an ascending aortic aneurysm. The diagnosis of idiopathic thombocytonenic purpura was also made by hematological studies which included the examination of the aspirated bone marrow. Preoperative chest computed tomography showed an ascending aortic aneurysm with a maximum diameter of 80 mm. Echocardiography demonstrated mild aortic regurgitation. The platelet count increased by intravenous administration of immunoglobulin. A prosthetic graft replacement of the ascending aorta and aortic valve repair were carried out with the aid of cardiopulmonary bypass, selective cerebral perfusion and hypothermic circulatory arrest. No difficulty was encountered in hemostasis and the postoperative course was uneventful. Histological examination of the aneurysmal wall showed chronic mesoaortitis with patchy destruction of musculo-elastic medial tissue and adventitial focal lymphocytic infiltrates that were similar to syphilitic mesoaortitis, although serological treponemal tests were all negative. Perioperative administration of gamma-globulin is useful to minimize the hemorrhagic complication in a patient undergoing cardiovascular surgery with idiopathic thrombocytopenic purpura.

Aged↗
PubMed2000

Surgical experience of the thoracic aortic aneurysm due to Takayasu's arteritis.

We have treated 10 patients with thoracic aortic aneurysms due to Takayasu's arteritis during the last 15 years and presented surgical results. In the surgical treatment of thoracic aortic aneurysm due to Takayasu's arteritis, therapeutic strategy is different from that for atherosclerotic aneurysm and should be determined by the location and the extent of aneurysmal lesions and the degree of inflammation. Palliative procedure, which was taken to reduce surgical risk, has failed to prevent the recurrence of aneurysmal formation or to minimize surgical risk in the later period. Radical surgical treatment for thoracic aortic aneurysms is highly recommended if technically possible. Penoperative steroid therapy to control the degree of inflammation, appropriate strategy for multiple or extensive lesions and progress in the organ protection method that enabled radical treatment, all these will contribute to the improvement of surgical results.

Adult↗
PubMed2000

Profound hypothermia and low flow cardiopulmonary bypass in resectioning a massive facial arteriovenous malformation.

A 44-year-old woman underwent resection of a massive facial arteriovenous malformation under profound hypothermia and low-flow cardiopulmonary bypass. A left ventricular vent through a small left anterior thoracotomy avoided ventricular distention associated with peripheral cannulation. Low-dose aprotinin was used to improve hemostasis. These techniques thus show promise for the safe application of profound hypothermic cardiopulmonary bypass in noncardiovascular operations.

Adult↗
PubMed2000

Midline exposure of the thoracoabdominal aorta.

Extended aortic replacement from the aortic arch to the descending thoracic or thoracoabdominal aorta has been performed through a left thoracotomy or a thoracoabdominal incision combined with or without a median sternotomy. However, a left thoracotomy incision may be unfavorable when dense adhesion of the lung is anticipated. We report a redo patient who underwent simultaneous replacements of the aortic arch and the thoracoabdominal aorta through a midline incision without entering the left pleural cavity.

Aged↗