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Takao Imazeki

Publications and source records attributed to Takao Imazeki.

9 recordsLinked to original sources
PubMed2006

[Aortic valve replacement through a partial sternotomy].

BACKGROUND: Instead of a median sternotomy which has been accepted as the standard approach to cardiaovascular surgery, we have selected a partial sternotomy as a minimally invasive surgery since 1997. Every technique and device must be reevaluated because the entire heart cannot be easily assessed. METHOD: In this paper we reported the pitfalls and results of 108 cases of aortic valve replacement through an upper and lower partial sternotomy. Single surgeon had used the single technique through the same operation field from 1997 to 2005. RESULTS: Mortality rate was 1.9% (2 patients). Aortic cross clamp time was a little longer in this series than in the conventional median sternotomy group. There were no differences in operating time, pumping time, intubation duration or bleeding. ICU stay and hospital stay were shorter in this series than in the conventional sternotomy group. The operating time was shorter in the regurgitation group than in the stenosis group. There were no differences in pumping time, intubation duration, bleeding, ICU stay or hospital stay. CONCLUSION: The minimally invasive cardiac surgery for the aortic valve replacement could be routinely and safely indicated.

Aortic Valve↗
PubMed2006

[Rupture of a chronic dissecting giant aneurysm into the pulmonary artery; report of a case].

Aortopulmonary fistula is an extremely rare complication of aortic dissection. We report a case of a chronic dissecting giant aneurysm with an aortopulmonary fistula. A 78-year-old woman experienced sudden onset chest pain and oppression. Chest X-ray showed ascending aortic and left ventricular enlargement and pulmonary congestion. Computed tomography (CT) confirmed the 100 mm ascending aortic aneurysm with dissection and aortopulmonary fistula. Operative repair was performed under profound hypothermic circulatory arrest with selective cerebral perfusion. The proximal and distal end were obliterated using a gelatin-resorcin-formaldehyde tissue glue and reinforced with a Teflon felt circumferential strip. The ascending aorta was replaced by a 30 mm coated Dacron vascular graft and the aortopulmonary fistula was closed with pledgeted vertical mattress suture. Postoperative CT showed a normally functioning vascular implant without any sign of aortopulmonary shunt or pulmonary artery stenosis.

Aged↗
PubMed2005

Venous drainage method for cardiopulmonary bypass in single-access minimally invasive cardiac surgery: siphon and vacuum-assisted drainage.

Vacuum-assisted venous drainage (VAVD) can facilitate venous drainage in single-access minimally invasive cardiac surgery (SAMICS). We retrospectively examined the use of VAVD in SAMICS in our hospital for this report. VAVD has been performed according to a VAVD protocol since 2000. Data from the 110 patients who underwent SAMICS in our institute from January 2000 to June 2002 were reviewed retrospectively. The total negative pressure was maintained at no greater than -90 mmHg. Indications for use of VAVD (protocol) were: insufficient venous return by siphon drainage alone, persistent elevation of the central venous pressure (CVP), and, insufficient venous drainage in the operative field. Of 110 patients, 97 (88.2%) underwent VAVD. The body surface area was significantly smaller in the group that did not require VAVD (the non-VAVD group) than in the group that did (VAVD group) (VAVD group versus non-VAVD group: 1.586 +/- 0.175 versus 1.408 +/- 0.153 m(2), P < 0.001). Other factors such as cardiopulmonary bypass time, aortic cross-clamp time, postoperative maximum lactate dehydrogenase, postoperative maximum creatinine, postoperative maximum blood urea nitrogen were similar in the two groups. VAVD is necessary in SAMICS except for small patients. A VAVD total negative pressure of -90 mmHg did not hinder operative procedures or cause clinical problems.

Adolescent↗
PubMed2005

Kommerell's diverticular rupture complicated by aberrant left subclavian artery and right aortic arch successfully treated surgically.

We report a rare case of a rupture in Kommerell's diverticulum in a 73-year-old woman with Edwards IIIB aberrant left subclavian artery (A-LSA) and right aortic arch. This case was further complicated by an inferior vena cava defect. We performed an emergency operation through a right posterolateral approach. The descending aorta was replaced and the Kommerell's diverticulum was excised, followed by A-LSA reconstruction, performed under deep hypothermia with selective cerebral perfusion. We believe the prognosis was excellent.

Aged↗
PubMed2004

[Surgical treatment for the valvular disease through partial sternotomy].

213 patients who underwent surgical treatment for the valvular disease through partial sternotomy were studied. We started the minimally invasive valvular surgery in July 1997. All the valvular diseases were indicated for the minimally invasive surgery except for the annulo-aortic ectasia and the concomitant disease with coronary artery bypass surgery. Ascending aorta was selected as an arterial cannulation place if we could choice it through intraoperative echocardiography. Venous cannulae 22-24 Fr were inserted into the venae cavae directly or through right atrium. Negative pressure venous drainage (maximally 90 mmHg) was performed if necessarily. We did single approach as possible. Mortality rate was 3.8%. We could complete 96.2% of our series as a minimally invasive surgery. Post operative intensive care unit (ICU) stay and hospital stay through partial sternotomy were significantly shorter than those through full sternotomy.

Aged↗
PubMed2003

Long-term follow-up of polyurethane vascular grafts for hemoaccess bridge fistulas.

The new polyurethane vascular graft (PVG) has been reported to be better than the expanded polytetrafluoroethylene (PTFE) graft in terms of early access and prompt hemostasis, but long-term patency and safety of PVGs have not been investigated objectively. To evaluate late clinical outcome of the PVG, we compared the complication and patency rates of stretch PTFE grafts with those of PVGs implanted for hemodialysis vascular access. Subjects were 53 patients who received 58 arteriovenous grafts between October 1997 and July 2000. They were divided in a prospective fashion into two groups according to the type of implanted graft: PVG ( n = 30) or PTFE ( n = 28). The study group comprised 27 men and 31 women with a mean age of 61.7 +/- 10.9 years (range: 23-84 years). The average number of previous accesses was 5.1 +/- 3.1 (range: 0-12). There were no differences between the groups in term of age, sex, body surface area, etiology of renal disease, presence of diabetes, previous access procedures, anatomical positions of grafts, or mean follow-up period. Primary patency rates for the PVG and PTFE grafts were equivalent at 1 year (60.7% vs. 56.5%) and at 2 years (54.7% vs. 51.8%). Similarly, secondary patency rates for the two groups did not differ at 1 year (78.7% vs. 79.9%) or at 2 years (78.7% vs. 69.3%). These findings indicate that the PVG is an acceptable alternative to the PTFE graft for blood access.

Adult↗
PubMed2003

Vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery.

This retrospective study evaluated the influence of vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery. A total of 104 patients who underwent cardiac surgery via minimal access incision were included in this study. Cardiopulmonary bypass was initiated with gravity alone, and vacuum-assisted venous drainage was applied only when the bypass flow was 2.2 l/min/m2 or less. We compared intraoperative variables of the patients to whom vacuum-assisted venous drainage (vacuum group) was applied with those who underwent gravity venous drainage alone (gravity group). In the 13 patients who most recently underwent isolated valve operations without maze procedures, free hemoglobin was measured to evaluate hemolysis. Vacuum-assisted venous drainage was required in 77 (72.6%) patients. Except for a smaller body surface area in the gravity group (P = 0.0118), patient characteristics did not differ significantly between the two groups. Free hemoglobin 60 mins after the beginning of cardiopulmonary bypass was higher in the vacuum group than in the gravity group (21.5 +/- 7.3 vs 11.1 +/- 7.1 mg/dl, P = 0.0284). Operative mortality and morbidity did not differ significantly between the groups. We found vacuum-assisted venous drainage to be a safe, simple, and effective technique in cases of minimally invasive cardiac surgery. However, there is a potential risk of hemolysis and air embolism, as shown in our findings and previous reports.

Blood Loss, Surgical↗
PubMed2003

Delayed blow-out type rupture of the right ventricle following blunt chest trauma.

A 36-year-old man suffered multiple traumatic injuries when he fell from a crane. Fractures of both lower extremities, a compression fracture of the fourth lumbar vertebra, and bilateral hemopneumothoraxes were identified. The sternum was not fractured, but was tender. The day after admission, the right ventricular free wall ruptured and was diagnosed by echocardiography. An emergency operation was performed. A Gore-tex sheet was sutured from inside the ventricle, and a Hemashield graft was sutured over the tear. The risk of hemorrhage is high in the patient with multiple traumatic injuries when heparin is required. Mechanical ventilation was required until the 13th postoperative day because persistent hemothorax. After an operation to reduce a leg fracture, the patient was discharged from the hospital on the 66th postoperative day.

Adult↗