15 results on '"M Imamaki"'
Search Results
2. Prediction of improvement in regional left ventricular function after coronary artery bypass grafting: quantitative stress-redistribution 201Tl imaging in detection of myocardial viability
- Author
-
M, Imamaki, T, Maeda, S, Tanaka, Y, Sugawara, and T, Shimakura
- Subjects
Male ,Thallium Radioisotopes ,Myocardial Ischemia ,Humans ,Female ,Heart ,Postoperative Period ,Coronary Artery Bypass ,Middle Aged ,Radionuclide Imaging ,Ventricular Function, Left ,Aged - Abstract
This study investigated the usefulness of quantitative assessment of Thallium-201 stress redistribution myocardial scintigraphy combined with quantitative assessment of regional left ventricular function using the centerline method for predicting of recovery regional left ventricular function following myocardial revascularization.Twenty patients with chronic total obstruction of the proximal portion of left anterior descending artery and/or right coronary artery were studied. Percent Tl-uptake method was used to evaluate myocardial viability before CABG. Regional LV function was evaluated before and after CABG with the centerline method. The territory of LAD was defined by chords 10 to 58 and that of RCA was defined by chords 59 to 80 in the centerline method. The parameter of regional left ventricular function was the mean (SF-Av.)/SD of each LAD and RCA territory.In cases showing a % uptake value under 50%, the preoperative value of (SF-Av.)/SD was -3.18+/-0.74 and postoperative value was -2.63+/-0.8 1. The difference between these values was not significant. When the %uptake value over 50%, the preoperative value of (SF-Av.)/SD was -2.80+/-0.49 and the postoperative value was -2.27+/-0.28. The postoperative value was significantly higher than the preoperative value(p=0.007).Even in cases of severe left ventricular dysfunction, regional left ventricular function improved if the value of % uptake in the redistribution Thallium imaging was 50% or over. Quantitative analysis of myocardial scintigraphy combined with quantitative analysis of left ventriculography is a useful method for predicting recovery of regional left ventricular function following myocardial revascularization.
- Published
- 2002
3. [Total arch replacement using prior selective cerebral perfusion]
- Author
-
M, Imamaki, M, Masuda, A, Ishida, H, Shimura, M, Hirano, K, Nishimura, N, Nakajima, and M, Miyazaki
- Subjects
Male ,Perfusion ,Survival Rate ,Blood Vessel Prosthesis Implantation ,Aortic Aneurysm, Thoracic ,Cerebrovascular Circulation ,Preoperative Care ,Humans ,Aorta, Thoracic ,Female ,Middle Aged ,Aged - Abstract
Prior selective cerebral perfusion is the method whereby selective cerebral perfusion and systemic perfusion start almost simultaneously, and the arch vessels are clamped. Cerebral circulation is isolated from systemic circulation to avoid cerebral embolization owing to detachment of atherosclerotic material from the aorta, caused by the "sandblasting" effect of high-velocity jets of blood exiting the aortic canula. Twenty-seven consecutive patients underwent total arch replacement for degenerative aortic arch aneurysm using prior selective cerebral perfusion from 1992 to 2001. Surgical death (within 1 month after operation) was 2 cases (7.4%), in-hospital death was 5 cases (18.5%). Systemic circulatory arrest time is almost equal to the time which distal anastomosis takes. The time was 81.4 +/- 24.3 minutes. Selective cerebral perfusion time was 194.9 +/- 30.9 minutes. Extracorporeal circulation time was 280.6 +/- 55.3 minutes. The time for emergence from anesthesia was 6.0 +/- 2.7 hours. Permanent neurologic dysfunction which was thought to occurred within 48 hours after surgery was noted in 1 case (3.7%). Postoperative survival at 8 years was 73.3%. There was 1 arch aneurismal related accident. Prior selective cerebral perfusion may be useful for avoiding cerebral embolization.
- Published
- 2002
4. [Surgical treatment of traumatic rupture of the aortic valve]
- Author
-
M, Imamaki, T, Shimakura, H, Kurihara, T, Maeda, and Y, Sugawara
- Subjects
Male ,Heart Injuries ,Aortic Valve ,Heart Valve Prosthesis ,Aortic Valve Insufficiency ,Accidents, Traffic ,Humans ,Middle Aged ,Wounds, Nonpenetrating - Abstract
Rupture of the aortic valve after a blunt chest trauma is rare. A 63-year-old man was injured in an automobile accident and was hospitalized elsewhere due to acute respiratory failure 4 days after the accident. On admission, he was intubated immediately. The patient did not respond to available medical treatments and was therefore transferred to our hospital. His condition was diagnosed as severe left heart failure, and an emergency operation was performed. The right coronary and non-coronary cusps were perforated and the commissure between the right coronary and non-coronary cusps was torn. The aortic valve was excised and a SJM 25 AEC prosthetic valve was inserted. The patient recovered well postoperatively.
- Published
- 1996
5. [A case report of a successful Redo Bentall operation]
- Author
-
M, Imamaki, A, Hashimoto, S, Aomi, A, Takazawa, M, Nonoyama, M, Hirai, M, Yashima, A, Morishita, and H, Koyanagi
- Subjects
Male ,Reoperation ,Time Factors ,Heart Valve Prosthesis ,Aortic Valve Insufficiency ,Humans ,Cardiac Surgical Procedures ,Middle Aged ,Aneurysm, False ,Blood Vessel Prosthesis - Abstract
An initial Bentall operation was performed on a patient aged 38 years with annuloaortic ectasia and aortic regurgitation. An echocardiogram and RI angiogram revealed a perigraft aortic aneurysm on the same patient aged 45 years. The aneurysm gradually developed and the maximum diameter reached 90 mm in size. The Redo-Bentall operation (Piehler modification) was successfully done once again on the same patient aged 56 years. The anastmosis between the right coronary orifice and the graft was detached on all sides. The anastmosis between the left coronary orifice and the graft was detached two thirds of all sides.
- Published
- 1996
6. [Selection of the surgical methods and surgical outcome of the distal arch aneurysm]
- Author
-
H, Niinami, A, Hashimoto, S, Aomi, A, Takazawa, M, Imamaki, S, Noji, and H, Koyanagi
- Subjects
Adult ,Heart Bypass, Left ,Male ,Perfusion ,Cardiopulmonary Bypass ,Aortic Aneurysm, Thoracic ,Humans ,Aorta, Thoracic ,Female ,Cardiac Surgical Procedures ,Middle Aged ,Aged ,Blood Vessel Prosthesis - Abstract
Between January, 1985, and December, 1993, 20 patients (18 males, 2 females; median age 65 years) underwent repair of aneurysms of the distal arch. fourteen patients had sacciform aneurysms and 6 patients had fusiform aneurysms. The approaching methods to the aneurysms were left thoracotomy in 3 patients and median sternotomy in 17 patients, including the so-called "door open method" in 2 patients. The supportive methods during surgery were left heart bypass using a centrifugal pump in 3 patients cardiopulmonary bypass with selective cerebral perfusion in 11 patients, and cardiopulmonary bypass with retrograde cerebral perfusion in 6 patients. The operative methods were patch closure in 4 patients, graft replacement using the inclusion technique in 13 patients, and total arch replacement using the exclusion technique in 3 patients. One patient who underwent left heart bypass died intraoperatively from intractable bleeding, one who had undergone selective cerebral perfusion died postoperatively of rupture of the distal anastomosis and two patients, who were supported with retrograde cerebral perfusion, died postoperatively because of perioperative myocardial infarction or rupture of the dissection arising from the aneurysm. There were three cases with cerebral complications postoperatively. These three patients were supported with selective cerebral perfusion. Graft exclusion technique using a prosthetic graft with three branches under the retrograde cerebral perfusion shortened cardiopulmonary bypass time and heart and brain ischemic time, so that this technique might reduce cerebral complications and should be a promising surgical treatment for the distal arch aneurysm.
- Published
- 1995
7. [Surgical treatment of aortico-left ventricular communication due to infective endocarditis]
- Author
-
H, Niinami, A, Hashimoto, S, Aomi, A, Takazawa, M, Imamaki, and H, Koyanagi
- Subjects
Fistula ,Heart Valve Prosthesis ,Heart Ventricles ,Aortic Valve Insufficiency ,Suture Techniques ,Aortic Diseases ,Rheumatic Heart Disease ,Humans ,Female ,Endocarditis, Bacterial ,Middle Aged ,Aneurysm, Infected ,Aortic Aneurysm - Abstract
A 51-year-old woman was referred to our institute for surgical treatment from an other hospital where she was diagnosed as having a mycotic aneurysm located at the aortic annulus due to infective endocarditis. The aneurysm communicated with the left ventricle, with aortic stenosis and regurgitation, mitral stenosis and tricuspid regurgitation caused by rheumatic fever. On admission to our institute, the infective endocarditis was at the healed stage. The mycotic aneurysm was located at the aortic annulus of the right coronary cusp, and was closed using a prosthetic patch with mattress sutures. Aortic valve replacement with a 19-mm St. Jude Medical prosthesis was then performed on this patch. The mitral and tricuspid valves were also replaced with 27-mm and 29-mm St. Jude Medical prostheses, respectively. The patient is doing well 1 year after surgery.
- Published
- 1995
8. [Transcranial Doppler measurement of middle cerebral artery blood flow during continuous retrograde cerebral perfusion]
- Author
-
H, Sakahashi, A, Hashimoto, S, Aomi, H, Tokunaga, T, Koyanagi, M, Imamaki, O, Tagusari, M, Hirai, M, Satoh, and H, Koyanagi
- Subjects
Adult ,Male ,Cardiopulmonary Bypass ,Aortic Aneurysm, Thoracic ,Ultrasonography, Doppler, Transcranial ,Aorta, Thoracic ,Middle Aged ,Blood Vessel Prosthesis ,Perfusion ,Aortic Dissection ,Hypothermia, Induced ,Cerebrovascular Circulation ,Monitoring, Intraoperative ,Humans ,Female ,Blood Flow Velocity ,Aged - Abstract
This is the first report of cerebral blood flow measurement with transcranial Doppler (TCD) during aortic arch reconstruction using continuous retrograde cerebral perfusion (CRCP) with deep hypothermia. Cerebral blood flow velocity was measured in 6 patients. CRCP was performed via the superior vena cava (SVC) at 30 cmH2O of internal juglar vein pressure and at 18 degrees C or lower of minimum bladder temperature. During the operation, the flow velocity of the middle cerebral artery (MCA) was continuously measured with TCD fixed on the temple. The cerebral blood flow during CRCP was different in each of the 6 patient. The retrograde MCA flow could be measured during CRCP in 3 patients, and the flow velocity was 11-60% of the MCA flow velocity before cardiopulmonary bypass. In the other 3 patients, retrograde MCA flow could not be detected during CRCP, but antegrade MCA flow could be found after antegrade perfusion was resumed. The antegrade flow velocity right after CRCP became more than the MCA flow before CRCP, which was regarded as a reaction due to cerebral ischemia. All the patients awoke within several (2-9) hours after operations and had no permanent neurological complications. But 2 patients developed drowsiness for several days after the operations; their CRCP times were 127 and 131 minutes. It is concluded that CRCP is a simple technique for brain protection, but the cerebral blood flow during CRCP is a simple technique for brain protection, but the cerebral blood flow during CRCP is different in each patient.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
9. [Experience in modified maze operation preserving the anterior internodal tract (AINT)]
- Author
-
H, Nakano, T, Shimakura, H, Ishidoya, M, Ishiyama, M, Imamaki, and M, Shibuya
- Subjects
Heart Valve Prosthesis Implantation ,Male ,Atrial Fibrillation ,Heart Valve Diseases ,Methods ,Humans ,Mitral Valve ,Female ,Middle Aged ,Aged - Published
- 1994
10. [Effectiveness of continuous retrograde cerebral perfusion for surgical treatment of aneurysms of the aortic arch--comparison with antegrade cerebral perfusion]
- Author
-
T, Akimoto, A, Hashimoto, S, Aomi, T, Hirayama, M, Kitamura, T, Koyanagi, M, Imamaki, F, Yamaki, O, Tagusari, and H, Koyanagi
- Subjects
Adult ,Male ,Perfusion ,Aortic Aneurysm, Thoracic ,Cerebrovascular Circulation ,Humans ,Aorta, Thoracic ,Female ,Middle Aged ,Aged - Abstract
Several methods have been used for an adjunct to perform operation of aortic arch aneurysms. However, their results were often not so reasonable. Recently retrograde cerebral perfusion was reported as a new adjunctive method. In our institute, for the past 6 and a half years from May 1985 to April 1992, 50 patients underwent reconstruction of the transverse aortic arch by using two methods of artificial cerebral perfusion. One method is continuous antegrade cerebral perfusion (ACP, for 32 patients), and the other is continuous retrograde cerebral perfusion (RCP, for 18 patients), each technique was combined with deep hypothermia (18-20 degrees C) and low flow perfusion (10-30 ml/kg/min) to lower half body performed from femoral artery. In our RCP circuit, an additional pump was used for cerebral perfusion to superior vena cava, but the circuit was much simpler than the circuit in ACP. We compared the two methods (ACP versus RCP) as regards to the following items and the results were showed in parentheses; hospital death (8/32, 25%: 2/18, 11%), respiratory complication (8.27, 30%: 3/18, 17%), neurological complication (7/29, 24%: 1/18, 5.5%), duration of extracorporeal circulation (306.8 +/- 74.5 min: 260.4 +/- 60.0 min), periods of pre-ECC in the operation (160.3 +/- 69.2 min: 117.7 +/- 35.3 min), duration of cerebral perfusion (113.6 +/- 45.4 min: 74.1 30.5 min) and amount of bleeding (3424 +/- 2881 ml: 1802 +/- 1291 ml). RCP has superior advantages in all of those in comparison with ACP. These results suggest that RCP is a useful adjunctive method for reconstruction of aortic arch with a low operative risk.
- Published
- 1993
11. ['Separate hypothermia' retrograde cerebral perfusion for repair of aortic arch]
- Author
-
M, Imamaki, M, Nakajima, T, Hirayama, H, Hikawa, S, Hagiwara, and I, Ideta
- Subjects
Aged, 80 and over ,Male ,Extracorporeal Circulation ,Aortic Aneurysm, Thoracic ,Aorta, Thoracic ,Middle Aged ,Blood Vessel Prosthesis ,Perfusion ,Aortic Dissection ,Postoperative Complications ,Hypothermia, Induced ,Cerebrovascular Circulation ,Humans ,Female ,Aged - Abstract
We have developed a new technique of retrograde cerebral perfusion. To avoid the disadvantages by deep hypothermia, and to protect the brain for longer time, we perfused from SVC cannula with blood cooled at 10-15 degrees C, at the same time from femoral artery with blood cooled at 20-26 degrees C. From October 1991 to December 1992, 8 patients underwent surgical repair using this method. By this method, the cases of which cerebral perfusion time were 147, 134, 125, 119, 110 minutes, did not have neurological deficits.
- Published
- 1993
12. [A case report of chronic traumatic dissecting aneurysm of the thoracic aorta]
- Author
-
M, Imamaki, A, Hashimoto, S, Aomi, H, Tokunaga, and H, Koyanagi
- Subjects
Male ,Aortic Dissection ,Chronic Disease ,Accidents, Traffic ,Humans ,Aorta, Thoracic ,Middle Aged ,Wounds, Nonpenetrating ,Aortic Aneurysm ,Blood Vessel Prosthesis - Abstract
A 63-year-old male, who sustained a blunt chest trauma in a traffic accident, was referred to our hospital for his traumatic aneurysm. An operative repair was undertaken 3 months after the trauma. The descending aorta was dissected along 5 cm, and its diameter was about 6 cm. Graft replacement was performed under the left heart bypass by using the BioMedicus centrifugal pump. He is doing well 3 years after the operation.
- Published
- 1991
13. [Frozen blood from one closely related donor reduced complications of blood transfusion without adverse effects in the open-heart surgery]
- Author
-
H, Namba, T, Hata, Y, Sone, S, Takada, M, Imamaki, M, Kuinose, and G, Taniguchi
- Subjects
Adult ,Cryopreservation ,Heart Defects, Congenital ,Male ,Adolescent ,Transfusion Reaction ,Blood Donors ,Middle Aged ,Blood Preservation ,Child, Preschool ,Freezing ,Humans ,Family ,Female ,Cardiac Surgical Procedures ,Child - Abstract
We used frozen blood from one closely related donor in 24 patients (group I) who underwent open heart surgery for congenital heart disease, in order to reduce of complications from a large quantity of blood transfusion. Blood of 600-2200 ml was collected from the single donor and was kept frozen until the operation. Two conditions of the patients were instituted, (1) body weight less than or equal to 40 kg (2) the single donor is father or mother or a close relative. The group of these patients was compared with patients using frozen autologous blood (group II) and patients using banked blood (group III). In group I patients two times of decline of red blood cell counts (RBC), hematocrit (Ht), hemoglobin (Hb) and total protein (TP) were noticed. The first was the period during the cardio-pulmonary bypass. The second was the time about one week after the transfusion of frozen red cells. But degree of the decline was uneventful clinically. The increment of complications induced from the use of frozen red cells was not noticed, and there was no case of serum hepatitis in group I patients. We concluded that the open-heart surgery using frozen blood cells (single donor), if the application was appropriate, could be undergone safely and would be effective on reducing infection and reaction induced from blood transfusion.
- Published
- 1990
14. [Post-operative evaluation of a 17 mm diameter Björk-Shiley Monostrut prosthesis for aortic valve replacement--pressure gradient and effective valve area]
- Author
-
T, Hata, H, Namba, Y, Sone, M, Imamaki, M, Kuinose, and G, Taniguchi
- Subjects
Reoperation ,Evaluation Studies as Topic ,Aortic Valve ,Heart Valve Prosthesis ,Humans ,Female ,Middle Aged - Abstract
A 17 mm diameter Björk-Shiley Monostrut prosthesis was implanted in a 64-year-old female for aortic valve replacement in a semi-emergency. This valve was one of the smallest valves which were available in Japan. The patient was admitted because of severe hemolytic anemia and heart failure. Echocardiography showed regurgitation and calcification of Ionescu-Shiley tissue valve which was implanted 5 years ago. The patient's body surface area was 1.2 m2. Because of narrow aortic annulus, we could barely implant a 17 mm diameter Björk-Shiley Monostrut prosthesis. The valve function was examined by Brockenbrough method. During catheterization, the heart rate was 85 b/min and cardiac index was 3.00 l/min/m2. In these hemodynamic conditions, simultaneous measurements of aortic and left ventricular pressures revealed only 9 mmHg mean systolic pressure gradient. Similarly, 20 mmHg of pressure gradient across the implanted valve was obtained by Gorlin's formula. We could calculate that the effective orifice area of a 17 mm diameter Björk-Shiley Monostrut prosthesis was 1.0 cm2. Postoperative echocardiography demonstrated 42 mmHg systolic pressure gradient across this prosthesis by Doppler techniques, and left ventricular wall thickness was not decreased. To best our knowledges, this was the first case in which post-operative evaluation such a small prosthesis was measured.
- Published
- 1990
15. [Surgical repair of TR and PC caused by cryosurgery of WPW syndrome]
- Author
-
T, Sato, M, Imamaki, H, Saito, H, Nakano, Y, Tuzuku, and N, Watanabe
- Subjects
Pericarditis, Constrictive ,Humans ,Female ,Wolff-Parkinson-White Syndrome ,Middle Aged ,Cryosurgery ,Tricuspid Valve Insufficiency - Published
- 1988
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.