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Hitoshi Hirose

Publications and source records attributed to Hitoshi Hirose.

At least 19 recordsLinked to original sources
PubMed2006

Slow earthquakes coincident with episodic tremors and slow slip events.

We report on the very-low-frequency earthquakes occurring in the transition zone of the subducting plate interface along the Nankai subduction zone in southwest Japan. Seismic waves generated by very-low-frequency earthquakes with seismic moment magnitudes of 3.1 to 3.5 predominantly show a long period of about 20 seconds. The seismicity of very-low-frequency earthquakes accompanies and migrates with the activity of deep low-frequency tremors and slow slip events. The coincidence of these three phenomena improves the detection and characterization of slow earthquakes, which are thought to increase the stress on updip megathrust earthquake rupture zones.

Journal Article↗
PubMed2006

Nonoperative management of traumatic aortic injury.

BACKGROUND: The standard management for patients with blunt aortic injury is surgery; however, a small number of patients have been medically managed. The outcome of these nonoperatively managed patients is unknown. METHODS: Seven patients diagnosed as blunt aortic injury were managed without aortic surgery between January 1993 and April 2002, and their outcomes were retrospectively investigated. RESULTS: There were three men and four women, with a mean age of 48.7+/-22.7 years and Injury Severity Score of 37.7+/-16.9. The reason for nonoperative management was refusal of surgery (2), do-not-resuscitate order (1), diffuse brain injury (2), small intimal tear (1), and technical difficulty (1). Two patients died resulting from associated injuries. Five patients are alive, and in three patients complete resolution of aortic injury was observed. CONCLUSIONS: In selected patients with multiple associated injuries or severe comorbidity, nonoperative management after blunt aortic injury can be a treatment of choice.

Adult↗
PubMed2005

Midterm results of mitral valve repair with artificial chordae in children.

OBJECTIVE: We have used artificial chordal replacement with expanded polytetrafluoroethylene sutures for mitral valve repair in children and reported favorable early clinical results. In this article we evaluate the midterm results of mitral valve repair with expanded polytetrafluoroethylene sutures in 39 children. METHODS: From April 1995 through September 2003, mitral valve repair with chordal replacement using expanded polytetrafluoroethylene sutures was performed in 39 patients. In all patients the preoperative grade of mitral regurgitation was moderate or more because of prolapse of the anterior mitral leaflet. The mean age and body weight at the time of the operation were 4.7 +/- 5.3 years (range, 1 month to 17.8 years) and 14.4 +/- 12.2 kg (range, 3.9-54.4 kg), respectively. The number of expanded polytetrafluoroethylene sutures ranged from 1 to 3 (mean, 1.4). The mean follow-up period and body weight at the latest follow-up were 5.0 +/- 2.3 years (range, 1.1-8.5 years) and 25.7 +/- 16.4 kg (range, 6.9-73 kg), respectively. RESULTS: There were no operative or late deaths. Only one patient required mitral valve replacement, which occurred 17 days after repair. Two patients underwent redo mitral valve repair 2 and 5 years after initial repair, respectively. The actuarial freedom from reoperation at 5 and 8 years was 94.8% and 89.5%, respectively. At the latest follow-up, trivial or less mitral regurgitation was observed in 33 (84.6%) patients. CONCLUSIONS: Mitral valve repair with expanded polytetrafluoroethylene sutures in children demonstrated favorable midterm outcome. The procedure is safe and effective, with potential for patients' growth.

Adolescent↗
PubMed2005

Acute subclavian artery occlusion by blunt trauma: a case report.

We report a case of acute left subclavian artery occlusion after blunt trauma, presenting with symptoms of acute left upper arm ischemia. Angiography was performed to confirm the injury. The injured left subclavian artery was approached via left thoracotomy, and an interposition graft was placed. The patient recovered without any complications.

Adult↗
PubMed2005

Systematic off-pump coronary artery bypass.

PURPOSE: We assessed the feasibility of systematic off-pump coronary artery bypass (OPCAB) and identified risk factors for on-pump conversion. METHODS: Between July 1, 2002 and December 31, 2003, OPCAB was attempted for all patients who required isolated coronary artery bypass in our institution. The perioperative results of patients were prospectively entered into a structured database, the results were analyzed to identify the risks of requirement of cardiopulmonary bypass. RESULTS: OPCAB was performed in all but 4 patients, giving an OPCAB success rate of 98.3% (229/233). The reason for cardiopulmonary bypass was hemodynamic instability occurring during reoperative surgery in 3, and cardiogenic shock in 1. The isolated risk factor for on-pump conversion was reoperation (relative risk 11.6). Mean number of distal anastomoses performed under OPCAB was 3.7+/-1.2, and the complete revascularization rate was 92.1% (211/229). There was one hospital death (0.4%). During a mean follow-up period of 1.0+/-0.4 years, two patients developed angina, which were treated with catheter intervention; otherwise, there was no death, or other cardiac events observed. CONCLUSION: Systematic OPCAB was feasible except in patients undergoing reoperative surgery or patients with on-going deep cardiogenic shock. Systematic OPCAB provided successful complete revascularization and its short term results were acceptable.

Aged↗
PubMed2005

Tetraplegia after coronary artery bypass, a rare complication.

Paraplegia after coronary artery bypass is rare. We present here a rare case of acute paraplegia after coronary artery bypass due to cervical disc herniation. This patient further developed respiratory failure due to denervation of respiratory muscles, resulting in tetraplegia. Prompt diagnosis with MRI and surgical decompression should be performed, otherwise permanent neurological impairment may occur.

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PubMed2004

Skeletonized radial artery grafting: one-year patency rate.

BACKGROUND: The skeletonized radial artery harvesting technique has routinely been used in our institute. Its clinical outcome is acceptable; however, the graft patency rate at 1 year has not been reported. METHODS: Between July 1, 2003, and October 31, 2002, 50 consecutive patients underwent isolated coronary artery bypass using skeletonized radial artery grafts in our hospital. There were no hospital deaths or perioperative myocardial infarctions. All patients completed follow-up by November 2003. Twenty of these patients (18 asymptomatic volunteers and 2 symptomatic patients) underwent coronary angiography at 1 year, and the results were analyzed. RESULTS: At a mean (+/-SD) follow-up period of 1.2 +/- 0.2 years, there were no deaths. Two patients developed angina due to graft occlusion (1 in the radial artery and another in the gastroepiploic artery). Twenty-one radial artery grafts and 36 distal anastomoses with radial artery grafts were evaluated by angiography at 1 year (0.9 +/- 0.1 years). There was 1 radial artery graft occlusion affecting 1 distal anastomosis, giving a perfect graft patency rate of 95.2% (20/21) and a perfect anastomosis patency rate of 97.2% (35/36). The patient with the occluded radial artery graft had a history of peripheral vascular disease and diabetes. There were no graft stenoses or string signs. CONCLUSION: At our limited follow-up, the results of using skeletonized radial artery grafts are excellent. Extensive skeletonization will not affect the graft patency rate or early graft spasm. Careful examinations of the radial artery grafts in patients with a history of peripheral artery disease and diabetes are mandated.

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PubMed2004

Skeletonized gastroepiploic artery for off-pump coronary artery bypass grafting.

BACKGROUND: Skeletonized arterial grafting may reduce the risk of graft spasm and may improve graft patency. Previously we reported a pilot study of skeletonized gastroepiploic artery (GEA) grafting with favorable results. Skeletonized GEA harvesting with an ultrasonic scalpel has now become our routine procedure. In this report, we compare the early clinical outcomes of skeletonized versus pedicled GEA grafting to assess the safety and benefit of use of skeletonized GEA in coronary artery bypass grafting. METHODS: Between July 2002 and October 2003, the GEA was used as a conduit for isolated off-pump coronary artery bypass grafting in 105 patients. Of these, 21 patients (group P) received pedicled GEA and 59 patients (group S) received skeletonized GEA grafts (excluding 25 patients whose results were reported in the pilot study). The perioperative and early follow-up data were prospectively collected and compared. RESULTS: No graft injury was found in either group. The preoperative characteristics were similar in the two groups except that group S had a smaller body surface area (1.64 +/- 0.16 m 2 in group S versus 1.73 +/- 0.16 m 2 in group P, P <.05) and a significant number of patients with diabetes (36/59, 61.0% versus 7/21, 33.3%, P <.05). The number of distal anastomoses was 4.3 < 1.0 versus 3.9 +/- 0.9 ( P = not significant [NS]). An in situ GEA composite graft was constructed in 8 (13.6%) of the patients in group S and none of the patients in group P ( P = NS). There was one hospital death due to infection in group S. Otherwise, there were no cases of low output syndrome or postoperative myocardial infarction in either group. During early postoperative follow-up, no angina recurrence or myocardial infarction was found. CONCLUSION: The GEA can be skeletonized safely with an ultrasonic scalpel. Skeletonization enables a wider variety of choices in the use of GEA grafting.

Adult↗
PubMed2004

Aortic nontouch off-pump complete revascularization using 3 in situ arterial conduits: bilateral internal mammary arteries and gastroepiploic artery.

BACKGROUND: Arterial grafts have been used frequently in recent coronary artery bypass grafting (CABG). Off-pump CABG can facilitate early patient recovery. A combination of in situ graft and off-pump technique results in complete aortic nontouch surgery; however, outcome has not been well established. METHODS: Between May 1998 and December 2001, 1035 consecutive isolated CABG operations were performed at Juntendo-Shin-Tokyo Hospital Group. Of these, off-pump CABG using in situ bilateral internal mammary arteries and in situ gastroepiploic artery was performed in 48 patients (41 men and 7 women; mean age, 74.5 +/-9.9 years). Perioperative and follow-up data were studied. RESULTS: The average number of distal anastomoses was 3.4 +/-0.7, and complete revascularization was achieved in all patients. There were no hospital deaths. Perioperative myocardial infarction was observed in 1 patient, congestive heart failure in 1, stroke in 2, and mediastinitis in 1. Postoperative catheterization was performed in 30 patients and revealed no graft occlusions. During the follow-up period of 2.3 +/- 1.2 years, no remote deaths, angina recurrence, or coronary interventions were observed. CONCLUSION: Off-pump CABG using an all in situ arterial graft can be performed safely, and follow-up results are excellent.

Adult↗
PubMed2004

Off-pump coronary artery bypass grafting for patients with left main disease.

BACKGROUND: Multivessel off-pump coronary artery bypass grafting (CABG) has been performed with favorable results in our institute. In this study, we analyzed the outcomes in patients who underwent off-pump CABG for left main disease, since the surgical outcomes for such patients have not been clarified. METHODS: Between March 1, 1999 and July 30, 2002, a total of 147 patients with left main disease (112 males and 35 females, mean age 66.9 +/- 9.8 years) underwent off-pump CABG. Perioperative and follow-up data were entered into a structured database and the results were analyzed. RESULTS: Urgent or emergent surgery was performed in 25 patients (17.0%), and a preoperative intra-aortic balloon pump was used in 12 patients (8.2%). The mean number of bypass grafts was 3.2 +/- 1.0, and complete revascularization was performed in 127 patients (86.4%). There were 4 incidences of intraoperative conversion from off-pump to on-pump surgery. The mean intubation period, intensive care unit stay and postoperative hospital stay were 9.4 +/- 13.0 h, 2.3 +/- 1.4 days and 13.4 +/- 7.3 days, respectively. There was 1 hospital death (0.7%). Postoperative myocardial infarction was observed in 2 patients (1.4%), postoperative stroke in 1 (0.7%), prolonged ventilator support in 5 (3.4%) and mediastinitis in 3 (2.0%). During the follow-up period of 2.1 +/- 1.0 years, there were 4 deaths and 7 cardiac events. The actuarial 3-year survival rate was 97.0%, and the event-free rate was 94.3%. CONCLUSION: Our observations support off-pump CABG as a surgical option with a favorable outcome for patients with left main disease.

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PubMed2004

Off-Pump Coronary Artery Bypass Using Skeletonized Gastroepiploic Artery, a Pilot Study.

Abstract Background: The problem with using the gastroepiploic artery (GEA)for coronary artery bypass grafting (CABG) is vasospasm. To minimize vasospasm of the GEA, a skeletonized harvesting technique was used for GEA harvesting. We present the initial results of GEA grafting using this technique. Methods: Between September 1, 2002, and December 31, 2002, a total of 25 patients (21 men and 4 women, mean age 65.4 +/- 8.7 years) gave informed consent and underwent elective off-pump CABG using the skeletonized GEA. Skeletonization was completed using an ultrasonic scalpel (Harmonic scalpel, coagulating-scissors; Ethicon Endo-Surgery, Cincinnati, OH, USA). Follow-up data were available until August 31, 2003. Perioperative, early clinical, and follow-up results were analyzed. Results: There were no hospital deaths, perioperative myocardial infarctions, congestive heart failure, strokes, or renal failure. There were no abdominal complications. Follow-up data were available from all patients, with a mean follow-up of 0.8 +/- 0.1 years. There were no cardiac deaths or cardiac events. Conclusion: During our limited follow-up period, the early results of skeletonized GEA grafting were excellent, and cardiac events have been well controlled. Mid-term follow-up study and angiographic study are necessary to confirm our initial clinical outcome data.

Journal Article↗
PubMed2004

Redo coronary artery bypass grafting: early and mid-term results.

OBJECTIVES: Redo coronary artery bypass grafting (CABG) has been gradually increasing in Japan. We prospectively collected redo-CABG data and evaluated these the early and remote results. METHODS: Between 01/01/1994 and 06/30/2002, a total of 71 patients underwent isolated redo-CABG in our hospital group. The interval between operations was 7.8 +/- 6.1 years. Previous surgery was CABG in all patients. Perioperative, early angiographic, and follow-up results were analyzed. RESULTS: The mean number of grafts was 2.9 +/- 1.2. There were 4 incidences of injury to the heart or graft during sternal re-entry or during dissection of the heart. There was 1 hospital death (2.8%) and 19 major complications (26.8%), including 7 patients (9.9%) with postoperative congestive heart failure and 2 (2.8%) with postoperative myocardial infarction. Postoperative angiography was obtained in 47 patients and their overall stenosis free patency rate was 93.9%. Follow-up was completed for all hospital survivors with a mean follow-up of 3.9 +/- 2.2 years. The event-free and survival rates at 5 years were 76.4% and 83.9%, respectively. CONCLUSION: In our limited experience, redo-CABG was performed with acceptable risks and its long-term results were satisfactory.

Adult↗
PubMed2004

Redo-aortic valve replacement after previous bilateral internal thoracic artery bypass grafting.

BACKGROUND: Aortic valve replacement (AVR) after coronary artery bypass using bilateral internal thoracic arteries (ITAs) is a challenge. Management of these patent grafts and myocardial protection are important issues. Moreover the risk and outcome of these complex operations have not been clearly defined. METHODS: Eighteen consecutive patients (all male) who exhibited previous bilateral ITA grafts underwent subsequent AVR surgery from 1990-2001 at the Cleveland Clinic Foundation. Their medical records were retrospectively analyzed. RESULTS: At the time of reoperation, the mean age of the patients was 67 +/- 6.4 years and 33 out of 36 (92%) ITAs were patent. The interval between previous coronary bypass and aortic valve surgery was 10.3 +/- 5.3 years. All patients underwent redo-median sternotomy with aortic cannulation in 12 patients (67%) and femoral or axillary artery cannulation in 6 patients (33%). The patent ITAs were clamped during aortic cross-clamping in 15 patients. In 3 patients the ITAs were not dissected. These 3 patients underwent deep hypothermic arrest for myocardial protection. Concomitant coronary revascularization was performed in 8 patients (44%). There were no hospital deaths. One stroke occurred but there were no other major complications. Average intubation time was 23.1 +/- 27.1 hours, intensive care unit stay was 2.3 +/- 3.1 days, and postoperative hospital stay was 10.3 +/- 7.6 days. CONCLUSIONS: Reoperative aortic valve surgery in the patients with patent bilateral ITA grafts can be performed safely.

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