Galacto-oligosaccharides ameliorate dysbiotic Bifidobacteriaceae decline in Japanese patients with type 2 diabetes.

Gut microbiota affects the host's metabolism, and it is suggested that there are differences in gut microbiota composition between patients with type 2 diabetes and healthy individuals. Additionally, dysbiosis may increase the concentration of lipopolysaccharides (LPS), causing metabolic endotoxemia, which induces impaired glucose tolerance. Several studies have reported relationships between metabolic diseases and the gut microbiota; and prebiotics, such as oligosaccharides, are commonly consumed to regulate gut microbiotas in healthy individuals. Galacto-oligosaccharides (GOS) are a major prebiotic, which specifically increase Bifidobacteriaceae abundance. Recent studies have reported that Bifidobacteriaceae improved metabolic endotoxemia or impaired glucose tolerance. However, there are few studies reporting the effects of GOS on patients with type 2 diabetes. In the current study, we compared clinical parameters, faecal gut microbiota, their associated metabolic products and their components such as LPS, and LPS-binding protein (LBP) produced by the host, between patients with diabetes and healthy controls. We then assessed the effects of GOS on glycaemic control, and gut microbiotas and metabolites in patients with type 2 diabetes in a double-blind controlled manner. LBP levels were significantly higher in patients with diabetes than those of healthy subjects, which was consistent with previous reports. The abundance of Bifidobacteriaceae and the diversity of intestinal microbiota were significantly lower in patients with diabetes than in healthy subjects. Interestingly, Bifidobacteriaceae was markedly restored in patients with diabetes after consumption of GOS, whereas LBP and glucose tolerance did not improve during this short-term trial period. In the present study, we demonstrated that GOS can ameliorate dysbiosis in patients with diabetes, and continuous intake of GOS may be a promising method for managing type 2 diabetes.

[Constrictive pericarditis after minimally invasive coronary artery bypass grafting: report of a case].

Constrictive pericarditis (CP) after off-pump coronary bypass surgery, especially after minimally invasive direct coronary artery bypass (MIDCAB), had rarely been reported. We presened a surgically treated case of CP after MIDCAB via left anterior small thoracotomy. A 57-year-old man underwent MIDCAB with placement of an internal mammary artery to the left anterior descending coronary artery uneventfully. Four years after the operation, he began to experience exertional dyspnea. Computed tomography of the chest showed pericardial thickening. Cardiac catheterization revealed elevation and equalization of the pressures in the 4 chambers, as well as low cardiac output. Pericardiectomy using cardiopulmonary bypass through a median sternotomy was performed successfully without injury to the bypass graft. Postoperative hemodynamic measurements were improved. The patient has resumed normal activity and remained free from heart failure for over 5 years.

[Evaluation of paravalvular leakage occurring after the 3rd mitral valve replacement].

We evaluated the frequency of paravalvular leakage (PVL) in 21 patients who had undergone mitral valve replacement (MVR) 3 times or more in our department between January 1981 and December 2003. Of these 21 patients, 5 underwent MVR 4 times, including the one who underwent the 5th MVR. Seven (38%) of 18 patients who had successfully undergone MVR 3 times and all 2 patients who had successfully undergone MVR 4 times developed PVL. PVL recurred in 6 (67%) of 9 patients who had undergone the 3rd MVR due to the occurrence of PVL. However, PVL recurred in only 1 (11%) of 9 patients who had undergone the 3rd MVR due to some postoperative complications other than PVL. Among 10 patients who developed PVL after the 1st or 2nd MVR, PVL recurred in 7 patients after the 3rd MVR. However, among 8 patients who did not develop PVL after the 1st or 2nd MVR, PVL occurred after the 3rd MVR only in 1 patient. These findings suggest that repeated MVR increases the incidence of PVL, and that patients with a past history of PVL are at a higher risk of developing PVL after repeated MVR.

[The strategy to avoid malperfusion of vital organs during operation for acute aortic dissection; multi-monitoring and right brachial artery perfusion].

BACKGROUND: Malperfusion of vital organs is the most serious complication during cardiopulmonary bypass for acute aortic dissection. METHOD: From 2001 to 2006, 40 patients underwent operation for acute type A aortic dissection. Right brachial artery perfusion was performed in 20 patients. From May 2005, transesophageal echocardiography and cerebral oxygenation measured by near infrared spectroscopy were continuously monitored during operation. RESULTS: There were 3 in-hospital deaths and 3 brain infarction. Switching of blood flow during cardiopulmonary bypass occurred in 3 patients; 2 patients suffered from diffuse brain infarction while. in the other patient, switching of perfusion was detected at once by multi-monitoring and resolved by induction of right brachial artery perfusion. CONCLUSION: Close monitoring of cerebral oxygenation by near infrared spectroscopy, transesophageal echocardiography and right brachial artery perfusion are effective in operation for acute aortic dissection.

[Long-term results of conventional aortic valve replacement for small aortic annulus].

We studied cardiac function, clinical outcome and quality of life (QOL) long after aortic valve replacement for pure aortic stenosis. Forty-four patients in small group [St. Jude Medical (SJM) 17 HP, 19 A], and 69 patients in non-small group (19 HP, 21 A, 23 A) operated on from 1984 to 2004 were enrolled in this study. We assessed the clinical data, aortic pressure gradient, left ventricular mass index (LVMI), and ejection fraction (EF) by preoperative and postoperative echocardiography. Moreover to evaluate QOL after the operation, we performed SF-36 used for the evaluation of health and QOL worldwide. Mean follow-up is 7.1 +/- 4.8 years in small group, and 6.8 +/- 4.6 years in non-small group. There were 2 hospital deaths in small group, and 1 in non-small group. The actual survival rate at 10-year were 89.2% in small group, and 85.6% in non-small group. There was no significant difference in hospital mortality, LVMI, long-term survival rate, and the scores of SF-36 between the 2 groups. The use of small sized prosthetic valves in patients with small aortic annulus might be justified when there is no patient-prosthesis mismatch.

[Early and long-term results of valve replacement in patients on chronic hemodialysis].

Cardiac valve replacement carries a high-risk in hemodialysis patients and has been questioned for its results. The purpose of this study is to focus on the early and long-term results in our institution. We retrospectively analyzed the data from 41 hemodialysis patients who underwent valve replacement in our unit from July 1978 to March 2004. Bioprosthetic valves were used in 5 patients (12.2%). The overall operative mortality (30 days) was 17%. The in-hospital death rate was 22%. Late survival rate was 68% at 2 years, 54% at 3 years, 49% at 5 years, and 27% at 10 years for all patients. The incidence of major bleeding and stroke was 41%.

[Lateral femoral circumflex artery for coronary artery bypass surgery in a patient receiving hemodialysis: report of a case].

A 59-year-old man receiving hemodialysis had a 2-vessel coronary disease. We performed double coronary artery bypass grafting with the left internal thoracic artery to the left anterior descending artery, and the composite graft of right internal thoracic artery and lateral femoral circumflex artery to the right coronary artery. Postoperative coronary angiogram showed that the LFCA bypass graft was widely patent and supplied sufficient blood to the anastomosed vessel. There was no stenosis at the anastomotic site. He had no postoperative complication. Long-term follow-up and more cases is necessary to establish the usefulness of LFCA as an arterial free graft for coronary revascularization in patients receiving hemodialysis.

[Two cases of reoperative coronary bypass grafting through a small left thoracotomy].

A reoperation by a MIDCAB (minimally invasive direct coronary artery bypass) was performed on 2 patients, including one who had undergone a surgical repair of a left ventricular rupture and another who had undergone a coronary artery bypass operation. In both patients, the left internal thoracic artery was isolated by a left small thoracotomy and then was anastomosed to the LAD (left anterior descending artery). One patient showed stenosis at the site of anastomosis and thus required coronary arterioplasty postoperatively, but was discharged without any further complications. When performing a reoperation by MIDCAB, complications such as injuries to the heart and patent graft during surgery and postoperative complications can be minimized by only performing a bypass to LAD. Such a bypass is usually sufficient in cases in which either marked adhesion is expected in the area of the circumflex artery or if anastomosable branches are not available in the area of the circumflex artery. This surgical technique was found to be an effective modality for a reoperation of the coronary artery, if suitable cases are carefully selected.

Comparison of durability of bioprostheses in tricuspid and mitral positions.

BACKGROUND: Few reports have assessed differences in the durability of mitral and tricuspid bioprostheses after simultaneous implantation of the same bioprosthesis in both positions. We investigated the long-term outcome after simultaneous mitral valve replacement (MVR) and tricuspid valve supraannular implantation (TVSI) with the Carpentier-Edwards bioprostheses in patients with severe tricuspid regurgitation and advanced mitral valve disease. METHODS: Between 1982 and 1998, 37 patients in our hospital underwent MVR and TVSI with Carpentier-Edwards bioprostheses. The mean age of the patients was 55+/-11 years. The average postoperative follow-up was 7.9+/-4.5 years after surgery (range 0 to 14.6 years, 315.1 patient-years). The follow-up rate was 100%. We evaluated the actuarial survival rate, the actuarial freedom from structural valve deterioration (SVD) and reoperation, and postoperative complications. RESULTS: The overall actuarial survival rate at 13 years after the operation was 69%+/-31%. The actuarial freedom from SVD and reoperation in the mitral and tricuspid positions were 78+/-22 and 100% and 70+/-30 and 90%+/-10% (p = 0.03), respectively. No patient had systemic or pulmonary thromboembolism, or complications associated with fatal arrhythmia. CONCLUSIONS: These results suggest that the bioprostheses in the tricuspid position yield significantly better long-term results than those in the mitral position after simultaneous MVR and TVSI.

Tricuspid valve supra-annular implantation in adult patients with Ebstein's anomaly.

BACKGROUND: Tricuspid valve supra-annular implantation (TVSI) has been performed for adult patients with Ebstein's anomaly at our hospital for several decades. TVSI is characterized by reliable reduction of tricuspid annulus size without affecting the conduction system; by prevention of residual tricuspid regurgitation (RTR) through preservation of the native tricuspid valve; and by implantation of the bioprosthesis at a supra-annular site. METHODS: Ten adult patients with Ebstein's anomaly underwent TVSI. The right ventricular diameter and residual tricuspid regurgitation were evaluated by echocardiography preoperatively, at discharge, 1 year after the operation, and over the long term (12.4 +/- 5.5 years). Actuarial survival rate, actuarial freedom from structural valve deterioration rate, and postoperative occurrence of arrhythmia were also evaluated. RESULTS: The actuarial survival rate at 19 years was 76 +/- 15%. Tricuspid regurgitation disappeared in 8 patients just after operation. Right ventricular diameter was significantly smaller at discharge than preoperatively (63 +/- 11 vs 37 +/- 9, p < 0.01), and there were no significant differences between values at discharge and at follow-up. The actuarial freedom from structural valve deterioration rate and the reoperation rate were both 100%. There were no fatal complications related to arrhythmia or thromboembolism. CONCLUSIONS: TVSI is useful for adult patients with Ebstein's anomaly. The absence of complications related to fatal arrhythmia and thromboembolism, good durability of the bioprosthesis, and a simple operative procedure are merits of this therapy.

Surgical strategy for severe tricuspid valve regurgitation complicated by advanced mitral valve disease: long-term outcome of tricuspid valve supra-annular implantation in eighty-eight cases.

OBJECTIVE: Although annuloplasty has been the most commonly performed surgical modality for severe tricuspid regurgitation, tricuspid valve supra-annular implantation has been performed in our hospital for more than a decade. The aim of this study was to assess the long-term outcome of tricuspid valve supra-annular implantation in a subgroup of patients with severe tricuspid regurgitation, those who also had advanced mitral valve disease. METHODS: Mitral valve replacement in conjunction with tricuspid valve supra-annular implantation was performed on 88 patients at our hospital between 1984 and 1998. The patients (mean age 57 +/- 11 years) were followed up for an average of 7.2 +/- 4.5 years after the operation (range 0-14 years); total follow-up was 643.1 patient-years. All patients except 2 (97.6%) were included in the follow-up. We evaluated the mortality, the cause of death, survival, the freedom from structural valve deterioration and reoperation, postoperative complications, and long-term echocardiographic findings. RESULTS: Overall survival at 14 years was 69% +/- 7.7%. Freedom from structural valve deterioration at 14 years was 100% and from reoperation, 88% +/- 9. 4%. There were no instances of pulmonary thromboembolism or of complications associated with fatal arrhythmias. Echocardiography showed little residual tricuspid regurgitation, no atrophic and stenotic change in the native tricuspid valve, and no thrombus formation between native valve and the implanted bioprosthesis. CONCLUSIONS: The procedure's simplicity, the good long-term durability of the bioprosthesis, and the absence of fatal arrhythmias and pulmonary thromboembolism indicate that tricuspid valve supra-annular implantation is a useful procedure for patients with severe tricuspid regurgitation complicated by advanced mitral valve disease.

Difference in structural change in the Carpentier-Edwards pericardial valves implanted in the mitral and tricuspid positions.

We report a 29-year-old patient with prosthetic valve dysfunction with severe calcific stenosis in the mitral position but no structural change in the tricuspid position after mitral valve replacement and tricuspid valve supra-annular implantation with same bioprostheses at the seven years before. The difference in structural change between the mitral position and the tricuspid position might be due mainly to the effect of mechanical stress on the cusps, rather than to any difference in serum calcium levels. However, some hormonal effect other than that of the parathyroid hormone on the systemic and pulmonary circulation might be related to the early progression in cusp calcification in the systemic circulation.

Retrospective analysis of cerebral complications after coronary artery bypass grafting in elderly patients.

The present study retrospectively investigated cerebral complications of coronary artery bypass grafting in 205 consecutive patients aged 70 years or older, who underwent elective cardiopulmonary bypass from 1990 to 1997. Computed tomography of the brain and chest was done before surgery. Ten patients had so-called 'aortic no-touch surgery' and suffered no cerebral complications; the other 195 patients had conventional surgery. Adverse cerebral events occurred in 8.7%, including cerebral infarction (4.1%), diffuse encephalopathy (1.0%), convulsions (1.0%), transient disturbance of consciousness (1.0%), and severe loss of volition (1.5%). Multivariate analysis showed that only the detection of calcification of the ascending aorta was significantly associated with cerebral complications (p = 0.029). Total clamping tended to be superior to partial clamping for prevention of cerebrovascular accidents. The mortality rate was 7.3%. In-hospital death was related to age (p = 0.0062), cerebral complications (p = 0.0032), and a low left-ventricular function (p = 0.018). Therefore, chest computed tomography to assess the ascending aorta should be performed preoperatively. Modified techniques like aortic no-touch surgery or other therapies combined with coronary intervention may be needed in elderly patients with severe calcification of the ascending aorta.

Venous function and delayed leg swelling following saphenectomy in coronary artery bypass grafting.

Some patients are troubled by leg swelling following saphenectomy long after CABG. Postsaphenectomy venous function in the leg has not, however, been well clarified. To determine whether venous dysfunction caused postsaphenectomy swelling, we measured the maximum venous outflow and time constant (tau) in the leg by venous occlusion strain-gauge plethysmography in 45 patients; a venous Doppler test was also conducted in 33 of the 45 at a mean 57.6 +/- 21.3 months after CABG. The saphenous vein was harvested unilaterally from the lower leg or from both the thigh and lower leg in all patients. Edema was seen in 4 patients (8.9%) and 8 reported leg swelling after saphenous vein harvest (17.8%). Legs were classified into three groups: group 1 consisted of 12 with edema or reports of swelling ipsilateral to the saphenous vein harvest site, group 2 consisted of 33 ipsilateral to the saphenous vein harvest without edema, and group 3 consisted of the 45 nonoperated-on, contralateral legs of the same patients as controls. No significant differences were seen in maximum venous outflow, tau, or the incidence of deep vein reflux among groups. No significant relationship was found between venous function and leg swelling occurring delayed after saphenectomy.

[The risk factors of emergency coronary artery bypass grafting in the elderly].

The purpose of this study was to evaluate the risk factor of emergency coronary artery bypass grafting (CABG) in the elderly. From January 1986 to December 1998, there were 37 patients of emergency CABG in 75 years old and over. They were divided into two groups (alive: 27 patients and dead: 10 patients). The risk factors that influenced the mortality were preoperative chronic renal failure and cardiogenic shock, prolonged cardiopulmonary bypass time and aortic cross clamp time, postoperative mediasinitis and perioperative cerebrovascular accident. In conclusion, the predictors of operative mortality of emergency CABG in elderly were preoperative cardiogenic shock and renal dysfunction.

[A surgically treated case of saccular true aneurysms in the ascending aorta].

A surgically treated case of saccular true aneurysms in the ascending aorta caused by cystic medial necrosis is reported. A 59-year-old woman, who had no findings of Marfan syndrome, was admitted to our hospital because of chest discomfort and dyspnea on exertion. Echocardiography showed that massive pericardial effusion and the dilated ascending aorta without dissection. No aortic valve insufficiency nor dilatation of the Valsalva's sinuses were found out. Chest CT scan and aortography also revealed that focal dilatation of the ascending aorta without the intimal flap and the false lumen. Because of the presence of cardiac tamponade, we performed an emergency operation without definite diagnosis of the ascending aortic lesion. Intraoperatively, 2 saccular aneurysms, which were 55 x 45 x 20 mm and 25 x 15 x 15 mm in size, were found out in the ascending aorta. The ascending aorta was replaced with a woven Dacron graft successfully. These aneurysms were histologically diagnosed as true aneurysms caused by cystic medial necrosis. Although saccular true aneurysms of the ascending aorta are rarely observed, they should be considered as one of ascending aortic diseases that cause cardiac tamponade potentially.

[Native aortic valve thrombus revealed by routine echocardiography: a case report].

A 75-year-old man presented with palpitations due to atrial flutter. Transthoracic echocardiography revealed a mobile aortic valve mass (17 mm in diameter) attached to the non-coronary cusp of the aortic valve. There was no evidence of hypercoagulative state. Computed tomography showed old cerebral infarction in the territory supplied by the right middle cerebral artery. The mass was surgically resected. The aortic valve was preserved because there were no organic changes in the valve. Histological examination demonstrated an organized thrombus. Only three cases of thrombus attached to the normal native aortic valve have been reported. Native aortic valve thrombus may be important in the differential diagnosis of aortic valve mass.

[A case of post-radiation constrictive pericarditis developing 12 years after radiation therapy].

A 70-year-old woman underwent radical mastectomy for carcinoma of the left breast in 1982. Postoperative radiation therapy was given in a total dose of 50 Gy for parasternal and left subclavian nodes. Symptoms of heart failure such as exertional dyspnea, facial edema, and hepatomegaly manifested in 1992. Cardiac catheterization revealed marked elevation of mean right atrial pressure and right ventricular end-diastolic pressure. The pressure wave form of the right ventricle showed the so called "dip and plateau" feature. Pericardiectomy without using extracorporeal circulation was performed in 1994. Operative findings and pathological study results were compatible with radiation-induced constrictive pericarditis. She rapidly recovered from heart failure after this operation, and has done very well to date.