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K Kawazoe

Publications and source records attributed to K Kawazoe.

At least 19 recordsLinked to original sources

Effect of the maze procedure for atrial fibrillation on atrial and brain natriuretic peptide.

We studied plasma levels of atrial and brain natriuretic peptides at rest and after exercise before and after intracardiac surgery with and without the maze procedure in patients with chronic heart failure secondary to valvular heart disease. The present study found that an increased response of both cardiac natriuretic peptides is attenuated with resulting water retention after the maze procedure.

Atrial Fibrillation

Serial evaluation of atrial function by Doppler echocardiography after the maze procedure for chronic atrial fibrillation.

The primary goal of the maze procedure is to prevent thromboembolism by restoring atrial function. We used Doppler echocardiography to evaluate the atrial function of patients who had undergone the maze procedure for the treatment of chronic atrial fibrillation. Thirty-five patients who converted to sinus rhythm after the maze procedure were enrolled in this study. Doppler echocardiography was performed in all patients in the early (mean, 19 days) and late (mean, 245 days) phases of the postoperative period. Left and right atrial active contraction fractions and left and right atrial storage fractions were calculated. The relationship between the pre-operative left atrial dimension and the left atrial active contraction fraction was evaluated in the late postoperative phase. The left atrial active contraction fraction was significantly increased in the late phase, but there was no change in the left atrial storage fraction. While the right atrial storage fraction was improved in the late phase, the right atrial active contraction fraction was increased even in the early phase. In patients with non-rheumatic mitral valve disease, a significant negative correlation was observed between the pre-operative left atrial dimension and the left atrial active contraction fraction in the late postoperative phase (r = 0.61; P < 0.05). However, no correlation between these parameters was observed in patients with rheumatic mitral valve disease. Atrial function was improved after the maze procedure. Serial difference were observed between left and right atrial function during recovery. Thus, in patients with non-rheumatic mitral valve disease, the left atrial dimension prior to the maze procedure may be useful in predicting the atrial contractile function postoperatively.

Atrial Fibrillation

Electrocardiographic nature of restored sinus rhythm after Cox maze procedure in patients with chronic atrial fibrillation who also had other cardiac surgery.

OBJECTIVE: To characterise heart rate variability and high frequency components of restored sinus rhythm after the maze procedure. The maze procedure for chronic atrial fibrillation may prevent thrombotic events and improve the quality of life. However, the electrocardiographic nature of restored sinus rhythm after the maze procedure has not been fully elucidated. PATIENTS AND METHODS: Between March 1993 and August 1995, 104 consecutive patients undergoing the maze procedure in combination with other cardiac surgery were studied. There were 100 long-term survivors (78 with mitral valve disease, 9 with aortic valve disease, 8 with congenital heart disease, and 5 others). Twenty age-matched patients with mitral valve disease who were in normal sinus rhythm preoperatively were enrolled as a control group. 30 days after surgery, the presence of arrhythmias and the circadian changes of heart rate variability were estimated by ambulatory electrocardiographic monitoring and the filtered P duration was evaluated by signal-averaged electrocardiogram. RESULTS: Restoration of sinus rhythm was observed in 73 of 100 cases. Subjects were classified into three groups according to their postoperative ambulatory electro-cardiographic monitoring findings: patients in group 1 (n = 73) (1a: 58 regular sinus rhythm; 1b: 15 sinus rhythm with frequent premature atrial contractions (> 1000/day); patients in group 2 (n = 21) still had persistent atrial fibrillation; and patients in group 3 (n = 6) required permanent pacemaker implantation because of sick sinus syndrome. The success rate of restoration of sinus rhythm was 88.3% if left atrial diameter was small (< 65 mm). Circadian changes in the low frequency to high frequency power ratio in group 1a were significantly diminished compared with control group (P < 0.01). Furthermore, the filtered P duration in group 1a (150 (20) ms) and group 1b (158 (23) ms) were longer than in the control group (122 (11) ms) (P < 0.01). CONCLUSIONS: The maze procedure may result in a decreased sinus response and non-uniform transmission of impulses in the atrium.

Adult

Can the maze procedure be combined safely with mitral valve repair?

BACKGROUND AND AIMS OF THE STUDY: The safety of combining mitral valve repair with the maze procedure for chronic atrial fibrillation in the surgical management of patients with mitral valve disease is not well elucidated. We present our operative results regarding mortality and morbidity after such combined surgery. As a comparison, our operative results after mitral valve repair in patients without chronic atrial fibrillation are presented. METHODS: Between April 1993 and December 1994, 39 patients with chronic atrial fibrillation underwent mitral valve repair and concomitant maze procedure (group 1) at the Iwate Medical University. During the same period, 36 patients with sinus rhythm and one patient with DDD pacemaker underwent mitral valve repair (group 2). In order to evaluate the operative risk, morbidity, and mortality of adding the maze procedure to mitral valve repair, total cardiopulmonary bypass time, aortic cross-clamp time, intraoperative blood loss, intubation period, and duration of ICU stay were compared between the groups. RESULTS: Total cardiopulmonary bypass time and aortic cross-clamp time in group 1 were longer than in group 2 (174.0 +/- 38.8 min versus 150.1 +/- 54.4 min; p = 0.032, 122.5 +/- 30.7 min versus 95.8 +/- 38.2 min; p = 0.0012). However, the duration of ICU stay, intubation period, and intraoperative blood loss were not different between the groups. There were no hospital deaths in either group. Four patients in group 1, and two patients in group 2 required re-exploration for bleeding (p = NS). Two patients in group 1, and none in group 2 required pacemaker implantation postoperatively (p = NS). Two patients in group 2, and none in group 2 had minor cerebral infarction (p = NS). At hospital discharge, 28 patients in group 1 (72%) and 35 patients (97%) in group 2 were in sinus rhythm. CONCLUSIONS: The maze procedure can be combined with mitral valve repair without adding undue operative risk to patients. Those patients with chronic atrial fibrillation undergoing mitral valve repair may be advised for the possibility of concomitant maze procedure.

Aged

[Adherence to valve repair surgery: from the mitral to the aortic valve].

Mitral valve repair for regurgitation has recently become more predictable based on its high reproducibility and excellent long-term durability. Since October 1992, mitral valve repair has been attempted in 123 patients with dominant regurgitation and achieved in 121 patients (98%). The hospital mortality was 1.7% and reoperation was carried out in five patients (4.1%). Follow-up study of mitral regurgitation by echocardiography showed that the regurgitation was trivial or none in 100 patients (88%), mild in 9 (8%) and moderate or over in 5 (4%). The indication of mitral valve repair is now being expanded to more complex lesions, ischemic papillary muscle rupture, active infective endocarditis and recurrent lesion. Furthermore, repair for insufficient aortic valve was begun in January 1994 and has been performed in 34 patients (87%) of 39 with aortic regurgitation. The hospital mortality was 2.9% and reoperation was needed in two patients (6%). The degree of aortic regurgitation after discharge was estimated as trivial or none in 23 patients (70%), mild in 7 (21%), and moderate in 1 (3%). The results of mitral valve repair support an aggressive approach toward mitral regurgitation with valve repair. Although aortic valve repair seems to be less satisfactory, a definite group of patients will benefit by preventing the need for a prosthetic valve.

Aortic Valve

Impaired endothelium-dependent vasorelaxation in peripheral vasculature of patients with thromboangiitis obliterans (Buerger's disease).

BACKGROUND: Thromboangiitis obliterans (TAO) is an occlusive arterial disease and a separate disease entity from atherosclerosis. It occurs mainly in the small and medium-sized vessels. Although the cause of TAO is unknown, systemic factors (immunological or humoral) may be involved in addition to abnormal peripheral microcirculation. Endothelium is now recognized as an important factor in the maintenance of microvascular circulation and the inhibition of platelet aggregation. This study examines the possible impairment of endothelium-dependent vasodilation in the peripheral vasculature of patients with TAO. METHODS AND RESULTS: Forearm blood flow (FBF) changes induced by the endothelium-dependent vasodilator acetylcholine, the endothelium-independent vasodilator sodium nitroprusside, and occlusion-induced reactive hyperemia were measured plethysmographically in eight patients with TAO and in eight healthy control subjects matched for age and smoking status. The increase in FBF response to intra-arterial acetylcholine infusion was lower in patients with TAO than in healthy control subjects (peak FBF, 22.9 +/- 2.9 versus 14.1 +/- 2.8 mL/min per dL of tissue volume; P < .01). In contrast, there was no significant difference in the increase in FBF response to sodium nitroprusside infusion between the two groups (peak FBF 13.1 +/- 4.0 versus 16.3 +/- 2.5 mL/min per dL of tissue volume; P = NS). In the case of reactive hyperemia, there were no significant differences between the two groups at any time points of hyperemia (peak FBF, 32.9 +/- 4.0 versus 31.4 +/- 3.3 mL/min per dL of tissue volume; P = NS). CONCLUSIONS: These results indicate that peripheral endothelium-dependent vasodilation is impaired in the nondiseased limb of patients with TAO. This type of vascular dysfunction may contribute to such characteristics as segmental proliferative lesion and thrombus formation in the peripheral vessels of patients with TAO.

Acetylcholine

Successful utilization of the median sternotomy approach in the management of descending necrotizing mediastinitis: report of a case.

We describe herein the case of a patient in whom a median sternotomy was successfully employed for mediastinal drainage in the treatment of descending necrotizing mediastinitis (DNM). Although most reports describe cervical or thoracotomy approaches, our experience strongly suggests that median sternotomy is a satisfactory alternative approach for treatment of this disease.

Adult

Nonobstructing accessory mitral valve tissue and ventricular septal defect.

A 4-month-old boy with ventricular septal defect was found to have accessory mitral valve tissue attached to the anterior leaflet of the mitral valve. Operation was successfully performed to excise the accessory mitral tissue in the left ventricular outflow tract and close the ventricular septal defect. Most previously reported cases with accessory mitral valve tissue were associated with left ventricular outflow tract obstruction. This boy had no pressure gradient across the left ventricular outflow tract. The indications for prophylactic excision of nonobstructing accessory mitral valve tissue in a patient with other forms of congenital cardiac disease are discussed.

Heart Septal Defects, Ventricular

Expression of bcl-2 oncogene product in primary non-Hodgkin's malignant lymphoma of the oral cavity.

The B-cell leukemia/lymphoma-2 (bcl-2) proto-oncogene is peculiar, as its product appears to provide survival advantage to B cells by blocking apoptosis. Expression of bcl-2 protein was analyzed in 54 cases of primary non-Hodgkin's malignant lymphomas of the oral cavity by immunohistologic staining of paraffin-embedded tissue. The immunophenotype of each tumor was established with the use of a panel of monoclonal and polyclonal antibodies to lymphoid cell differentiation antigens. The cases in the present study were 42 B-cell lymphomas, 7 T-cell lymphomas and 5-lymphomas revealing histiocytic markers. Sixteen of the 42 B-cell lymphomas were positive for bcl-2 protein, and were composed of 7 low-grade B-cell lymphomas and 9 high-grade B-cell lymphomas. Seven low-grade B-cell lymphomas were composed of one mucosa-associated lymphoid tissue type, three centrocytic types and three centroblastic-centrocytic types. Nine high-grade B-cell lymphomas comprised four centroblastic types, one immunoblastic type and four lymphoblastic types. Enhanced expression of the bcl-2 oncogenic protein was detectable in lymphoma cells in 2 cases for the T-cell lymphoma, and one case for the true histiocytic lymphoma. In contrast to the previous reports of American node-based lymphomas, Japanese primary oral lymphomas in our series expressed a lower frequency of bcl-2 protein. Furthermore, the present study indicated that bcl-2 protein was expressed on a wide variety of B-cell lymphomas, T-cell lymphomas and true histiocytic lymphoma, and that differences in bcl-2 protein expression may be useful in the diagnostic separation of lymphoblastic lymphoma with B-cell marker from Burkitt's lymphoma.

Adult

[A case report of total cavopulmonary connection following total cavopulmonary shunt].

A 20-year-old man underwent total cavopulmonary shunt for univentricular heart type A (A.L.L.) with hemiazygos connection six years ago. Four years later, his condition deteriorated with easy fatigue and cyanosis. Cardiac catheterization showed recanalization of ligated SVC. Chest CT showed tight adhesion between the chest wall and the ascending aorta. We approached the heart through left anterolateral thoracotomy in order to avoid injury of the aorta and the ventricle during redo median sternotomy. Total cavopulmonary connection with intraatrial conduit was performed under circulatory arrest and retrograde cardioplegia without aortic cross clamp. His postoperative course was satisfactory. Left thoracotomy was useful for total cavopulmonary connection following total cavopulmonary shunt associated with postoperative adhesion.

Adult

Cell viability of aortic allografts after long-term cryopreservation and clinical application to aortic root replacement in a patient with aortitis.

A key point in the establishment of a tissue cryopreservation system is to maintain cell viability for an extended period. The viability of the tissue cells in the authors' cryopreservation system was examined, and the first clinical application reported. The tissue culture method demonstrated 95% of rat aortas (21 of 22 specimens) and 88% of human cardiac valves (seven of eight) to be viable after 6.4 months and 5.8 months of cryopreservation, respectively. The first clinical case, a 54-year-old man with aortic valve replacement and complications of aortitis, underwent successful aortic root replacement. Whereas the use of allografts in aortitis cases is controversial, such an approach was assumed reasonable because the mechanical stress between the native aortic annulus and the inserted valve could be reduced by aortic root replacement with the allograft.

Adult

Surgical management of infective endocarditis associated with cerebral complications. Multi-center retrospective study in Japan.

To establish guidelines for the surgical treatment of patients with infective endocarditis who have cerebrovascular complications, we conducted a detailed retrospective study of 181 of 244 patients with cerebral complications among 2523 surgical cases of infective endocarditis of the Japanese Association of Thoracic Surgery. The results showed that 9.7% of all patients with infective endocarditis had associated cerebral complications: 108 (44.3%) had active native valve endocarditis, 96 (39.3%) had healed native valve endocarditis, and 40 (16.4%) had prosthetic valve endocarditis. The hospital mortality of the patients with cerebral complications was 11.0% in the group as a whole: 13.9% in active native valve endocarditis, 3.1% in healed native valve endocarditis, and 37.5% in prosthetic valve endocarditis. Diseased valves included the following aortic valve in 55.5%, mitral valve 49.8%, tricuspid valve in 1.3%, and pulmonary valve in 1.3%. In 181 patients with cerebral complications, organisms were detected as follows: gram-positive cocci in 133 (73.5% [Streptococcus in 85, Staphylococcus in 32]), gram-negative in 18 (9.9%), fungus in 11 (6.1%), and unknown in 64.6%, cerebral bleeding in 31.5%, cerebral abscess in 2.8%, and meningitis in 1.1%. Hospital mortality rate and an exacerbation rate of cerebral complications, including related death, according to the interval from onset of cerebral infarction to cardiac surgery, were as follows: 66.3% and 45.5% within 24 hours, 31.3% and 43.8% between 2 and 7 days, 16.7% and 16.7% between 8 and 14 days, 10.0% and 10.0% between 15 and 21 days, 26.3% and 10.5% between 22 and 28 days, and 7.0% and 2.3% over 4 weeks later, respectively. A significant correlation existed between the interval and the exacerbation of cerebral complications (tied p = 0.008). Preoperative risk factors affecting exacerbation of cerebral complications were as follows: (1) severity of cerebral complications (p = 0.006), (2) intervals (p = 0.012), and (3) uncontrolled congestive heart failure as indications for cardiac surgery (p = 0.014). One patient underwent a cardiac operation within 24 hours of the onset of cerebral hemorrhage and died of cerebral damage. No exacerbations occurred in 10 patients who underwent their operation between 2 and 28 days. Nevertheless, exacerbations occurred in 19.0% of patients whose operation was done more than 4 weeks later. These data suggest that cardiac operations can be done safely 4 weeks after cerebral infarction, and if the delay is more than 2 weeks, the exacerbation rate will be around 10%. The risk of progression of cerebral damage is still significant 15 days and even 4 weeks after cerebral hemorrhage.

Adult

Transient cortical blindness following bypass graft angiography. A case report.

Transient cortical blindness, an uncommonly recognized complication of cerebral angiography, is an exceedingly rare event after cardiac catheterization and angiography. This report describes a sixty-two-year-old patient who had transient cortical blindness following bypass graft angiography. In this case, the authors showed that cortical blindness was associated with the breakage of the blood-brain barrier (BBB) and an increase in vascular permeability rather than with primary cerebral circulatory insufficiency. When the possibility exists that an excess volume of contrast medium may enter the cerebral circulation as in this case, that is, following a coronary artery bypass graft (CABG) using the internal mammary artery (IMA), precautionary measures may be necessary such as changing the type of contrast medium to be used or decreasing the volume injected. When cortical blindness occurs, it is a serious clinical problem whether transient or permanent. Therefore, the circumstances leading to this complication should be understood to determine suitable treatment and management.

Blindness

Immunophenotypes of Reed-Sternberg cells and their variants: a study of 68 cases of Hodgkin's disease.

Utilizing a panel of monoclonal and polyclonal antibodies, routine paraffin sections in 68 cases of Hodgkin's disease were examined for the presence of immunoreactivity in Reed-Sternberg (R-S) and related cells by the avidin-biotin-peroxidase complex (ABC) technique. In 14 cases of lymphocyte-predominant Hodgkin's disease (LPHD), R-S cells and the polyploid lymphocytic and histiocytic (L & H) variants of R-S cells were immunoreactive for L26 and alpha 1-antitrypsin (alpha 1-AT) in 9 (64%) and 6 (43%), respectively, whereas the remaining antibodies were negative or rarely positive against L & H variants of R-S cells. R-S cells in 24 cases of mixed cellularity Hodgkin's disease (MCHD) were positive with alpha 1-AT in 63% of cases, positive with LN3 in 71% of cases and positive for BerH2 in 92% of cases. The lacunar cell type of R-S cells in 19 cases of nodular sclerosing Hodgkin's disease (NSHD) were reactive for alpha 1-AT in all cases, BerH2 in 18 cases (95%), and LN3 in 17 cases (89%). Pleomorphic variant of R-S cells in 11 cases of lymphocyte depleted Hodgkin's disease (LDHD) showed reactivity with alpha 1-AT in 9 cases (82%), BerH2 in 6 cases (55%), and LN3 in 9 cases (82%). The incidence of L26 in R-S cells was higher in LPHD than in other three subtypes, whereas the immunohistochemical finding of alpha 1-AT had reverse relevance to the result of L26. The incidence of BerH2 in MCHD and NSHD was higher than that of this antibody in the whole of Hodgkin's disease. R-S cells in NSHD and LDHD were highly positive to LN3, and detection rate of these two types was higher than that in the whole of Hodgkin's disease. No cases showed immunoreactivity with anti-T-cell antibodies (CD3, UCHL1 and DFT1), a marker for natural killer cell (Leu7), and a marker for interdigitating reticulum cell (S-100 protein). These results suggest that correlation between predominant staining pattern and R-S cells and variants thereof in each histological subtype of Hodgkin's disease are as follows: LPHD shows L26+, alpha 1-AT-, BerH2-; MCHD and NSHD show L26-, alpha 1-AT+, BerH2+; and LDHD shows L26-, alpha 1-AT+, BerH2+ or L26+, alpha 1-AT+, BerH2-.

Antibodies, Monoclonal