Biomedical subjects

Toshinobu Kazui

Publications and source records attributed to Toshinobu Kazui.

7 recordsLinked to original sources

PubMed2006

Aortic valve myxoma mimicking vegetation: report of a case.

We report a case of cardiac myxoma of the aortic valve. To our knowledge, this represents only the seventh such case ever documented. A 61-year-old woman underwent an echocardiography to screen for hypertensive-diabetic cardiac complications, which showed a mass on her aortic valve. Although she had not experienced a fever, the mass closely resembled a vegetation, resulting in an initial diagnosis of infective endocarditis. We extirpated the mass and repaired the aortic valve with the patient under cardiopulmonary bypass. The postoperative course was uneventful. Histological examination confirmed that the mass was a myxoma.

Aortic Valve↗

PubMed2006

Initial clinical experience with the Heartstring.

OBJECTIVE: The Heartstring is one of the devices that enable proximal anastomosis without clamping the aorta. We have applied the device not only to low-risk patients with normal aortas but also to high-risk patients with diseased aortas. The purpose of this study was to investigate the initial outcomes of using this device. METHODS: The Heartstring was used on 87 patients between January and December 2004. The patients comprised 62 men and 25 women 48-86 years old (mean 68.4 +/- 8.4 years). The ascending aorta was evaluated by computed tomography (CT) scanning before surgery. If a patient's aorta was severely calcified, epiaortic echocardiography was performed. The aortas were ranked into four grades, and the preoperative patient's status were evaluated by the EuroSCORE. Angiography was performed on the third postoperative day. RESULTS: CT scanning revealed that 74 patients had no calcification in the ascending aorta, 10 patients had scattered calcification, and 3 patients had plate-like calcification. The EuroSCORE was 6.86 +/- 1.03. We performed 93 proximal anastomoses and 149 distal anastomoses. The average distal anastomosis was 1.6 +/- 0.6 sites per graft. Of the distal anastomoses, 74.2% were to the circumflex artery territory. Postoperative coronary angiography revealed that all grafts were patent. CONCLUSION: The Heartstring facilitates safe proximal anastomosis, even in high-risk patients. Their short-term outcome was good. The device assists in bypassing circumflex artery territory. Long-term follow-up is necessary.

Aged↗

PubMed2006

Aortic valve repair for aortic regurgitation: intermediate-term results in patients with tricuspid morphology.

BACKGROUND AND AIM OF THE STUDY: Surgical results after aortic valve repair in patients with aortic regurgitation (AR) of tricuspid valve morphology and with no evidence of aortic root disease have not yet been clarified. METHODS: Between January 1994 and June 2001, aortic valve repair was performed in 40 patients (eight females, 32 males; mean age 61.0 +/- 10.5 years) of this type. Surgical results and follow up data were summarized after aortic valve repair (for AR) in these patients. RESULTS: One patient died in hospital (mortality 2.5%). The mean cardiopulmonary bypass time was 143.5 +/- 47.4 min, and mean aortic cross-clamp time 99.8 +/- 34.3 min. At follow up, the mean AR grade was 1.5 +/- 0.8 and mean NYHA class 1.0 +/- 0; both parameters showed significant improvement compared to preoperative status (p < 0.0001). Survival was 94.9% at one year and 82.6% at five years. The five-year reoperation-free rate was 87%. CONCLUSION: Aortic valve repair for AR in patients with tricuspid valve morphology is a safe procedure that provides good intermediate-term results.

Aortic Valve Insufficiency↗

PubMed2006

Dynamic morphologic changes in the normal aortic annulus during systole and diastole.

BACKGROUND AND AIM OF THE STUDY: The three-dimensional motion of semilunar attachment of the leaflet 'annulus' remains obscure. It has been suggested that the aortic root is distensible and moves during the cardiac cycle. In the present study, the aortic root was evaluated using two dimensions. The aortic root, notably motion of the aortic annulus, was evaluated using multidetector computed tomography (MDCT), and a three-dimensional reconstruction of the aortic annulus was performed. METHODS: Twenty-five patients (17 males, eight females) underwent MDCT. None of the patients had aortic root disease, aortic valve disease, bicuspid valve, myocardial infarction or atrial fibrillation. The aortic annulus was measured in systole and diastole, and divided into three parts: the right coronary cusp (RCC), left coronary cusp (LCC) and non-coronary cusp (NCC). The lengths of the aortic annulus, sinus of Valsalva and sinotubular junction (STJ) were also measured in systole and diastole on longitudinal views. RESULTS: The lengths of each aortic annulus part in systole and diastole were as follows. In systole: RCC 41.8 +/- 8.1 mm; LCC 39.3 +/- 5.9 mm; NCC 43.7 +/- 7.1 mm. In diastole: RCC 42.4 +/- 7.0 mm; LCC 38.6 +/- 7.8 mm; NCC 41.5 +/- 7.8 mm. No statistically significant differences were observed between lengths in systole and diastole. The longitudinal lengths of aortic annulus, sinus of Valsalva and STJ at each period were as follows. In systole: aortic annulus 22.5 +/- 2.2 mm; sinus of Valsalva 34.9 +/- 4.3 mm; STJ 28.1 +/- 3.2 mm. In diastole: aortic annulus 22.1 +/- 2.2 mm; sinus of Valsalva 34.4 +/- 4.7 mm; STJ 27.2 +/- 3.1 mm. The length of the STJ in systole was significantly greater than that in diastole. CONCLUSION: In the normal aortic root, no part of the aortic annulus changed length during the cardiac cycle. According to changes in aortic root dimensions, the commissures move outwards during the systolic phase.

Adult↗

PubMed2005

Effective use of fibrin glue for acute aortic dissection.

The use of gelatin-resorcine-formalin (GRF) glue for reconstruction of the vascular wall in the context of acute aortic dissection has become more common. However, anecdotal evidence suggests that use of the GRF glue results in higher rates of postoperative redissection. We describe an alternative method of reinforcing the dissected aorta with fibrin glue that may avoid this complication. A fabric sheet is presoaked in fibrinogen solution and then placed within the false lumen. Thrombin solution is then applied to the fabric sheet. That results in obliteration of the false lumen and effective reinforcement of the dissected wall.

Aortic Aneurysm, Thoracic↗

PubMed2004

[Acute mitral valve insufficiency caused by chordae rupture].

The common causes of mitral valve chordae rupture are myxomatous valve disease, infective endocarditis. Acute mitral valve insufficiency from chordae rupture, severe clinical symptoms such as dyspnea and shock are observed. Diagnosis is made with clinical symptoms, chest X-ray and echocardiography. Echocardiography is very useful to evaluate the exact lesions. First, inotropic agents, dilators and intraaortic balloon pumping (IABP) are used to stabilize hemodynamic status. Once hemodynamic status becomes unstable in spite of such therapy, surgical correction of mitral regurgitation (MR) is considered. Mitral valve repair should be the first choice of surgical repair, because it preserves left ventricular function, avoids anti-coagulation therapy. Quadrangular resection and suture, annuloplasty and artificial chordae are reliable surgical techniques. If mitral valve repair is difficult, mitral valve replacement is another option. From 1994 to 2002, there were 12 patients who underwent emergency mitral valve surgery because of chordae rupture. There were 7 men and 5 women with mean age of 52.7+/-14.3 years old. Nine of them received mitral valve repair. Two patients were infective endocarditis. Preoperative MR grade was 4.0+/-0.0. Postoperative MR grade was 0.2+/-0.2. Mean follow-up period was 3.8 years. There were no cardiac events and reoperations. Repair technique is quite reliable even in patients with multiple lesions, and the surgical results were almost same as single lesion patients. Repair technique should be the first choice to treat acute MR caused by chordae rupture.

Aged↗

PubMed2003

Combined aortic and mitral valve repair.

Six patients, median age 63.3 years (range, 54 to 68 years), underwent concomitant mitral and aortic valve repair from January 2000 to August 2001. Surgical reports and general clinical data were reviewed retrospectively. All patients had degenerative valvular disease, although one patient also had annuloaortic ectasia. There were no surgical complications. The 30 day survival rate was 100%, and the New York Heart Association classification score improved from 2.2 (range, 1 to 2) preoperative, to 1.0 (all patients) postoperatively (p = 0.03) As measured by intraoperative transesophageal echocardiography, the left ventricular end-diastolic diameter decreased from 6.0 cm (range, 5.4 to 6.3 cm) to 4.7 cm (range, 4.0 to 5.2 cm) and the left ventricular end-systolic diameter decreased from 3.7 cm (range, 3.4 to 4.1cm) to 3.1 cm (range, 2.9 to 3.7 cm). No patient developed endocarditis, thromboembolism or hemorrhage. There was no valve related morbidity during a 1 year follow up. Double valve repair is an acceptable alternative to valve replacement in selected patients with some types of valvular disease. Longer term follow up with greater numbers of patients is needed.

Aged↗