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Hitoshi Terada

Publications and source records attributed to Hitoshi Terada.

30 records · Page 2Linked to original sources
PubMed2004

Thoracoabdominal aortic replacement for abdominal aortic aneurysm with atypical coarctation of thoracoabdominal aorta following mitral valve plasty.

We successfully treated a case of a 65-year-old female with an abdominal aortic aneurysm coexisting with an atypical coarctation of thoracoabdominal aorta and celiac axis and superior mesenteric artery occlusion. A dilated inferior mesenteric artery was supplying the celiac artery and superior mesenteric artery regions. The patient also had mitral regurgitation. After a mitral valve plasty, we repaired the abdominal aortic aneurysm and the atypical coarctation of the thoracoabdominal aorta using partial extracorporeal circulation, segmental clamping, and a selective perfusion of both the bilateral renal artery and dilated inferior mesenteric artery. The patient had an uneventful hospital course and remains well.

Aged↗
PubMed2003

Late reoperation for proximal aortic and arch complications after previous composite graft replacement in Marfan patients.

BACKGROUND: Marfan patients who received composite graft replacement for proximal aortic disease frequently require late reoperation. The initial surgical technique for this lesion remains controversial. METHODS: Fourteen Marfan patients who received composite graft replacement for annuloaortic ectasia with or without aortic dissection required late reoperation thorough re-median sternotomy. The techniques used for an initial composite graft replacement were the original Bentall procedure in 11 patients, the Cabrol procedure in 2, and coronary button technique in 1. Reoperation was indicated for prosthesis-related complications in 10 patients, distal aortic lesion in 13, or for both lesions in 8. Reoperations were performed, on average, 8.4 years after an initial operation. Reoperative procedures included re-composite graft replacement in 1 patient, total arch replacement in 5, and re-composite graft replacement with total arch replacement in 8. RESULTS: There were two in-hospital deaths (14.3%). Although pseudoaneurysms of the coronary artery or distal aorta occurred in the original Bentall or Cabrol procedures, true aneurysms of the coronary artery were noted even in the coronary button technique. Six patients required a total of eight subsequent descending or thoracoabdominal aortic replacements for an aneurysmal formation of a distal false lumen. CONCLUSIONS: The coronary button technique, with a small side hole for coronary anastomosis, is the procedure of choice for annuloaortic ectasia because it reduces the risk of coronary artery-related complications. Concomitant total arch replacement may be recommended for annuloaortic ectasia with DeBakey type I aortic dissection in selected patients to avoid the risk of reoperation on the aortic arch.

Adult↗
PubMed2003

Mechanical properties of various z-stent designs: an endovascular stent-grafting perspective.

PURPOSE: To comparatively assess the mechani-cal behavior of various clinically relevant Z-stent designs. METHODS: A total of 16 Z-stents of original, biliary, spiral, and double-skirted designs (n=4 for each) were constructed using similar specifications for all. Stents were then evaluated for stiffness, snap opening force (SOF), flexibility, and displacement force using a novel tensiometer. Differences among the stents were determined using statistical methods. Stents explanted from dog aorta after a mean follow-up of 13 months were examined under a scanning electron microscope for surface defects. RESULTS: Forces required for about 50% reduction in diameter were 1.88 +/- 0.16 N, 3.81 +/- 0.21 N, 2.76 +/- 0.22 N, and 3.35 +/- 0.19 N for original, biliary, spiral, and skirted designs, respectively. Differences among the four designs were statistically significant at almost all points of measurement (P < 0.0001). Biliary and skirted designs showed higher SOF values in the early measurements. Stents explanted from dog aorta after a mean duration of 13 months showed no obvious corrosion or breakage in the wire struts. CONCLUSIONS: Significant differences exist among the various Z-stent designs in terms of their mechanical properties. Understanding them should help to select the appropriate stent for a given lesion. 316L stainless steel shows a favorable long-term tissue interaction.

Angioplasty↗
PubMed2002

Total aortic arch replacement for thoracic aneurysm involving an isolated left vertebral artery.

We conducted 4 total aortic arch replacements in patients with an isolated left vertebral artery. In all 4, surgery was done using 4-branched arch grafts with moderately hypothermic selective cerebral perfusion and systemic circulatory arrest. All reconstructed isolated left vertebral arteries anastomosed to the native left subclavian artery or to the graft branch for this artery showed good patency. None of our patients had cerebral complications and all were discharged in good condition.

Aged↗
PubMed2002

Aortic root replacement using a homograft for recurrent valve endocarditis.

Prosthetic valve endocarditis is a relatively rare condition associated with high mortality. Endocarditis affecting 2 successive mechanical valves at the aortic position has not, to the best of our knowledge, been described. We reported such a patient whose condition was further complicated by mitral regurgitation, pulmonary hypertension, worsening heart failure, and cardiac conduction abnormalities. Considering the failure of 2 previous mechanical valves, we conducted a homograft replacement of the aortic root with coronary reattachment. Mitral regurgitation was treated by annuloplasty. The patient's early postoperative course was uneventful and he was doing well 16 months after surgery. We discuss the overall treatment strategy for recurrent prosthetic valve endocarditis and potential homograft advantages.

Adult↗
PubMed2002

Total and subtotal aortic replacement for extensive aortic dissection in patients with or without Marfan's syndrome.

OBJECTIVES: Extensive aortic dissection with multiple entries often found in Marfan's syndrome patients ultimately requires replacement of the whole aorta. We present a surgical strategy and results for total and subtotal aortic replacement. METHODS: Subjects were 18 patients, including 14 Marfan's patients undergoing total (n = 13) or subtotal (excluding aortic arch) aortic replacement (n = 5), for DeBakey type I aortic dissection (n = 13) and DeBakey type IIIb aortic dissection with annuloaortic ectasia (n = 5) between February 1991 and April 2001. Mean age was 39.9 +/- 0.8 years--34.9 +/- 6.6 years in Marfan's patients vs. 57.7 +/- 4.7 years in non-Marfan patients. All operations were staged, with the mean number required per patient 3.1 +/- 0.8. RESULTS: Early mortality was 0% and late mortality 11% (2 of 18). Paraplegia or paraparesis occurring in 11%. Except for these patients, all current survivors enjoy good quality of life. CONCLUSIONS: Total and subtotal aortic replacement for extensive aortic dissection may decrease mortality due to rupture or associated disease.

Adult↗
PubMed2002

Surgical outcome of acute type A aortic dissection: analysis of risk factors.

BACKGROUND: The aim of this study was to assess the risk factors for the early and late outcome of the surgical treatment of acute type A aortic dissection. METHODS: From 1983 to 2000, a total of 130 patients underwent operation for acute type A aortic dissection. Extent of distal aortic resection included ascending aorta in 19 patients (15%), hemiarch in 29 (22%), and total arch in 82 (63%). In all, 31 preoperative and perioperative variables were analyzed using univariate and multiple logistic regression models for independent predictors of in-hospital mortality and risk of late reoperation. After excluding in-hospital deaths, risk factors for late death were analyzed by Cox proportional hazard analysis. RESULTS: In-hospital mortality was 19.2% (25 of 130 patients). Multivariable analysis indicated that renal/mesenteric ischemia and shock were independent predictors of in-hospital death. At 10 years, the actuarial survival rate including in-hospital mortality was 70.9% +/- 4.7%, and the reoperation event-free rate was 73.5% +/- 5.7%. Aortic valve resuspension was an independent predictor of proximal aortic reoperation, whereas nonresection of intimal tear and younger age were independent predictors for distal aortic reoperation. Chronic obstructive pulmonary disease was the only independent predictor for late death. CONCLUSIONS: Patients' preoperative dissection-related complications and comorbidities significantly affect early and late survival rates after surgical treatment of acute type A aortic dissection.

Acute Disease↗
PubMed2002

Usefulness of antegrade selective cerebral perfusion during aortic arch operations.

BACKGROUND: To evaluate the safety and usefulness of antegrade selective cerebral perfusion (SCP) during arch aneurysm or aortic dissection operations. METHODS: Between January 1986 and December 2001, 330 patients underwent aortic arch repair using SCP. Operations were performed with the aid of hypothermic extracorporeal circulation, SCP, and systemic circulatory arrest in most cases. In all, 89 patients (27%) were operated on for acute aortic dissection, 77 (23%) for chronic aortic dissection, and 164 (50%) for degenerative aneurysm. Total arch replacement using a branched graft was performed in 288 patients (94%). Mean SCP time was 86.2 +/- 28.5 minutes. RESULTS: The overall in-hospital mortality rate was 11.2% (falling to 3.2% in the 124 patients operated on between 1997 and 2001). Independent determinants of hospital mortality were pump time, renal/mesenteric ischemia, chronic renal failure, increasing age, period of operation, and nonuse of four-branched arch graft. The overall postoperative incidences of temporary and permanent neurologic dysfunction were 4.2% and 2.4%, respectively. There was no significant correlation between SCP time and in-hospital mortality or neurologic outcome. CONCLUSIONS: Selective cerebral perfusion is a reliable technique for cerebral protection and it facilitates complex and time-consuming total arch replacement.

Adolescent↗
PubMed2002

Impact of an aggressive surgical approach on surgical outcome in type A aortic dissection.

BACKGROUND: To evaluate the impact of an aggressive surgical approach on early and late outcome in type A aortic dissection. METHODS: From 1983 to 2001, 240 patients underwent operation for acute (n = 138) and chronic (n = 102) type A aortic dissection. The extent of distal aortic resection included the ascending aorta in 39 (16%) patients, hemiarch (HAR) in 47 (20%), and total arch (TAR) in 154 (64%), including 19 patients who also had their descending aorta replaced (DAR). RESULTS: The in-hospital mortality did not differ between TAR with or without DAR and other more conservative techniques (12.3% versus 16.3%). Actuarial survival at 10 years including in-hospital mortality was 72.4% +/- 3.3% and freedom from reoperation was 77.2% +/- 3.6% for all patients: neither was influenced by the extent of distal aortic resection or acuity of aortic dissection. Multivariate analysis revealed younger age and failure to resect the intimal tear to be independent determinants for late reoperation. However, in contrast to 22 patients who had more conservative operations, none of the patients with TAR required reoperation on the aortic arch through a sternotomy incision. CONCLUSIONS: An aggressive surgical approach did not adversely influence early and late survival following type A aortic dissection; it reduced the necessity of late reoperation and facilitated distal aortic reoperation.

Adult↗
PubMed2002

Histological changes in canine aorta 1 year after stent-graft implantation: implications for the long-term stability of device anchoring zones.

PURPOSE: To examine aortic histology 1 year after stent-graft implantation in a canine model as a means of assessing the durability of endograft fixation. METHODS: Fourteen mongrel dogs each received 1 stent-graft and 1 bare stent placed endoluminally in the abdominal aorta. Eight animals were followed for 1 year, 3 for 4 to 8 weeks, and the remaining 3 for 24 to 48 hours. Aortic specimens were stained with hematoxylin-eosin, elastica-van Gieson, and Masson's trichrome and examined with light and electron microscopy and immunohistochemistry to identify smooth muscle cells (SMC), endothelialization, aortic wall ultrastructure, and changes at the device anchoring sites. RESULTS: No dilatation or dissection was noted at any of the device anchoring sites. The aortic media at 1 year was remarkably decreased in thickness: 891 +/- 196 microm in the control tissue versus 388 +/- 70 microm for the proximal stent-grafted aorta and 457 +/- 148 microm for the bare-stented aortic segment. Other important histological features were reduced elastic lamellae in the stent-grafted aorta versus control (p<0.0001), increased SMC density in the stent-grafted aortic region (p<0.0001 versus control), and absence of inflammatory infiltrate. Complete neointimal covering and endothelialization of the luminal endograft surface were found. SMCs generally showed no ultrastructural features of necrosis. CONCLUSIONS: Aortic stent-grafts induce distinctive histological changes in the aortic wall at 1 year, even when implanted in a healthy aorta. Although there is considerable medial elastin loss, an increased medial SMC density, an exuberant neointima, and a general absence of perigraft inflammation suggest an ongoing process of structural restoration at the device anchoring sites.

Animals↗
PubMed2002

Simultaneous carotid endarterectomy, coronary artery bypass grafting and abdominal aortic aneurysm surgery.

A case with a disease triad of an ulcerative lesion in the left internal carotid artery (LICA), severe coronary insufficiency, and an infrarenal abdominal aortic aneurysm (AAA) is presented in whom we performed simultaneous carotid endarterectomy (CEA), coronary artery bypass grafting (CABG), and Y-graft replacement of the AAA. The operative technique is detailed and justification of the simultaneous approach in such patients is discussed.

Aortic Aneurysm, Abdominal↗