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Objectives: Although the “mechanical valve” has historically been the popular choice to use as a prosthetic valve to treat dialysis patients requiring aortic value replacement (AVR) for aortic stenosis, bioprosthetic valves have also started to be considered for use, due to improvements of surgical outcomes observed through its technical improvements. In this study, we demonstrated our valve treatment strategy and investigated the early outcome to patients with dialysis. Methods: 470 patients received an AVR between January 2009 and December 2012. We retrospectively reviewed and analyzed the clinical course of 32 patients with dialysis. 15 patients were male and 17 patients were female, with an average age of 72.4 ± 7.3 years (range: 57-86 years). The mean duration of hemodialysis was 8.7 years (range: 0.1-36 years). The mean Society of Thoracic Surgery score and Euro Score II was 17.0% and 8.9%, respectively. We used a bioprosthetic valve for patients aged >65 years. Results: Mean observation period was 958 days. Regarding early mortality, there were 5 operative deaths within 30 days after operation (15.6%). There were 6 operative late deaths (20.7%). 1- and 3-year survivals in the bioprosthetic valve group were 68% and 46%, respectively. On the other hand, those in the mechanical valve group were 75% and 50%, respectively. Conclusion: The use of bioprosthetic valves should be considered due to its added benefits and because there is no statistically significant difference on survival and valve-related complications between bioprosthetic and mechanical valve group.

Several cases of traumatic ventricular septal defect (VSD) have been reported. However, traumatic VSD complicated by tricuspid rupture is rare. We report a case of traumatic VSD with tricuspid rupture who required repeated repair of both conditions. A 69-year-old man was transferred to our hospital for emergent surgical repair of traumatic VSD and tricuspid rupture. Although emergent repair was performed, a new left-to-right shunt and moderate tricuspid regurgitation appeared during his postoperative course. A reoperation was performed 4 months after the first operation. The borders of the defect were very fibrotic and strong compared with those in the first operation. Surgical treatment of traumatic VSD should be postponed in hemodynamically stable patients. When emergent repair is performed, careful follow-up is necessary to diagnose new VSD.

Coronary revascularization methods continue to be refined, and the emergence of the drug-eluting stent (DES) has especially changed clinical practice related to ischemic heart disease. For chronic hemodialysis (HD) patients, however, the impact of DES on clinical outcome is yet to be determined. Forty-six consecutive chronic HD patients who underwent myocardial revascularization in our institute were retrospectively reviewed. Twenty-eight patients underwent coronary artery bypass surgery (CABG) and 18 patients underwent percutaneous coronary artery intervention (PCI). Patient characteristics were similar between the two groups. In the CABG group, bilateral internal thoracic artery (ITA) bypass grafting was performed in 27 patients and off-pump CABG was performed in 20 patients. In the PCI group, a DES was used in 12 patients. The number of coronary vessels treated per patient was higher in the CABG group (CABG: 4.25 +/- 1.32 vs. PCI: 1.44 +/- 0.78; p < 0.001). Two-year survival rates were similar between the two groups (CABG: 94.1% vs. PCI: 73.9%; p = 0.41), but major adverse cardiac event-free survival (CABG: 85.9% vs. PCI: 37.1%; p = 0.001) and angina-free survival (CABG: 84.9% vs. PCI: 28.9%; p < 0.001) rates were significantly higher in the CABG group. The one-year patency rate for the CABG grafts was 93.3% (left ITA: 100%, right ITA: 84.6%, sapenous vein: 90.9%, gastro-epiploic artery: 100%), and six-month restenosis rate for PCI was 57.1% (balloon angio-plasty: 75%, bare metal stent 40%, DES: 58.3%). Even in the era of DES, clinical results favored CABG. The difference in clinical results is due to the sustainability of successful revascularization.

Objective: It is well known that the presence of carotid artery stenosis increases the risk of perioperative stroke in patients undergoing cardiac surgery with cardiopulmonary bypass. Although off-pump coronary artery bypass grafting (CABG) can avoid the adverse effects of cardiopulmonary bypass, the influence of carotid artery stenosis on the incidence of stroke in patients undergoing off-pump CABG has not been well clarified.Methods:We conducted a retrospective study of 461 patients who underwent elective off-pump CABG after screening for carotid artery stenosis at our institute between September 2004 and May 2007. The incidence and etiologies of stroke were identified. Preoperative screening revealed significant carotid artery stenosis in 49 patients. Clinical results were compared between patients with and without carotid artery stenosis. Results: Postoperative stroke occurred in two (0.43%) of the 462 study patients, and in-hospital mortality occurred in three (0.65%). Stroke was due to decreased perfusion resulting from hypovolemic shock in one and thrombosis in the other. There was neither stroke nor inhospital mortality in patients with carotid artery stenosis, although there were two strokes (0.49%) and three in-hospital mortalities (0.73%) in patients without carotid artery stenosis. Conclusions: The influence of carotid artery stenosis on the incidence of perioperative stroke may be little in off-pump CABG, especially in patients with moderate carotid artery stenosis. # 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Background Surgery for acute type B aortic dissection is associated with significant mortality and morbidity. The purpose of this study was to assess the clinical outcome of surgical management of complicated acute type B aortic dissection. Methods During the last 5 years, 112 patients were admitted for acute type B aortic dissection. Of these patients, 24 consecutive patients were enrolled who underwent surgical management during the acute or subacute stage. The mean age was 66.7 ± 9.1 years; 8 patients were female. Indications for surgery were rupture in 10 patients, impending rupture in 7, and malperfusion in 7. Fifteen patients were transferred from another hospital. The overall clinical outcome including morbidity, aorta-related events, and death were retrospectively assessed. Results The mean duration from the time of onset to surgery was 7.1 ± 9.0 days. Graft replacement of the aorta included the total aortic arch with cerebral perfusion in 6 patients, and replacement of the distal aortic arch or descending aorta with left heart bypass in 12. The remaining 6 patients underwent peripheral bypass for ischemia. Significant complications occurred in 7 patients (24.8%). The operative mortality rate was 8.3% (2 of 24); 5.6% (1 of 18) with central operation and 16.7% (1 of 6) with peripheral operation. The 5-year survival rate was 82.6 ± 7.9% and freedom from aorta-related events at 1 and 5 years were 95.2% ± 4.7% and 68.0% ± 16.6%, respectively. Conclusions Surgical management of patients with complicated acute type B dissection has an acceptable perioperative risk and survival. This study suggests earlier surgery with left heart bypass may be beneficial for appropriate patients.

Background The site of cannulation for repair of ascending aortic dissection remains controversial. The objective of this study was to evaluate the incidence and management of intraoperative malperfusion syndrome using femoral cannulation for repair of acute type A aortic dissection. Methods Between May 2002 and February 2007, 107 patients with initial femoral artery cannulation for the repair of type A aortic dissection were enrolled in this study. The mean age was 63.7 ± 11.8 years; 51 patients were female. Preoperative findings indicated malperfusion in 16 patients. Intraoperative malperfusion syndrome was diagnosed by both radial arterial pressure measurements and transesophageal echocardiography. Clinical outcomes, including specific operative procedures and complications related to the cannulation, were assessed. Results The ascending aorta was replaced in 59 patients, hemiarch in 16, and total aortic arch in 32. Intraoperative malperfusion syndrome was noted in 3 patients (lowering of radial pressure in 2, obstruction of the true lumen in 1) at the initiation of cardiopulmonary bypass. After immediately switching to transventricular cannulation, the surgical replacement was successfully performed. The remaining 104 patients underwent surgery during femoral artery bypass without perfusion abnormalities. There was 1 in-hospital death (0.9%), but no deaths among the malperfusion patients. Cerebrovascular deficit occurred in 7 patients (6.5%). One vascular and 3 wound complications occurred related to the femoral cannulation. Conclusions During the repair of acute ascending aortic dissection, malperfusion syndrome related to femoral artery cannulation has an acceptable incidence, and can be managed under appropriate intraoperative monitoring, particularly at the initiation of cardiopulmonary bypass.

Background The treatment strategy of acute intramural hematoma involving the ascending aorta remains uncertain. The objective of this study was to evaluate the effectiveness of surgical treatment for this condition. Methods A total of 41 patients underwent operation for acute intramural hematoma involving the ascending aorta between 2000 and 2006. Mean age was 67.2 ± 10.1 years, with 26 female patients and 10 in cardiogenic shock at presentation. Early and midterm results, including mortality, morbidity, survival, event-free rates, and the persistence of residual hematoma, were analyzed retrospectively in all patients. Mean follow-up period was 29.7 ± 18.1 months. Results All but one patient underwent operation within 72 hours from the onset of symptoms. Thirty-four patients underwent isolated ascending aortic replacement, three had hemiarch repair, and four required total arch replacement. There were no in-hospital deaths. Stroke occurred in two patients and transient neurologic dysfunction in one. Postoperative computed tomographic scan showed residual distal hematoma progression to classical double-barrel dissection in two patients. At five years follow-up, survival was 100%. During the follow-up period, one patient had a new type B aortic dissection. A follow-up study confirmed hematoma resorption in 29 patients (70.7%). The estimated freedom from intramural hematoma-related events was 92.6 ± 4.1% at five years. No independent predictor of intramural hematoma-related events was found on multivariate analysis. Conclusions Immediate surgical treatment of acute aortic intramural hematoma involving the ascending aorta with open distal replacement of ascending aorta results in lower mortality rates and excellent midterm survival.

A chitinolytic bacterium was isolated from Lake Suwa and identified as Aeromonas hydrophila strain SUWA-9. The strain grew well on a synthetic medium containing colloidal chitin as sole carbon source. Chitin-degrading activity was induced by colloidal chitin or N-acetylglucosamine (GlcNAc). Most of the activity, however, was not detected in culture fluid but was associated with cells. A beta-N-acetylglucosaminidase was purified after it was solubilized from cells by sonication. The purified enzyme hydrolyzed N-acetylchitooligomers from dimer to pentamer and produced GlcNAc as a final product. The enzyme also hydrolyzed synthetic substrates such as p-nitrophenyl (pNP)-N-acetyl-beta-D-glucosaminide and pNP-N-acetyl-beta-D-galactosaminide. A gene coding for the purified beta-N-acetylglucosaminidase was isolated. The ORF identified is 2661 nucleotides long and encodes a precursor protein of 887 amino acids including a signal peptide of 22 amino acid residues. The amino acid sequence deduced showed a high similarity to those of bacterial beta-N-acetylhexosaminidases classified in family 20 of glycosyl hydrolases.

僧帽弁閉鎖不全症に膵島細胞腫瘍を合併した症例を経験した.症例は76歳女性,僧帽弁閉鎖不全症III°のため手術目的に入院.術前CT検査にて膵尾部に1.5cm大の腫瘤を認めた.腹部血管造影も施行し膵島細胞腫と診断された.腫瘍の悪性度,腫瘍手術における心疾患の耐術性を検討し,僧帽弁置換術(Carpentier Edward生体弁)を先行,身体的,精神的回復を待ち, 3カ月後に膵体尾部切除を行った.膵腫瘍の病理所見は膵島細胞腫であった.

Low-dose aspirin (325 mg/day), administered to those with several conditions involving ischemic disorders, can cause upper gastrointestinal (GI) complications. In this prospective study, we aimed to clarify the incidence of aspirin-induced gastric ulcers in consecutive Japanese patients and identify suitable preventive measures.We recruited 125 consecutive adult outpatients who received low-dose aspirin (enteric-coated tablets 100 mg) for8 weeks. Endoscopy and blood tests were used to evaluate their gastric injury (which was scored using a modified Lanza scale) and anti-Helicobacter pylori antibody titer, respectively.We found that 39.8% of patients received either no upper GI drug or only mucoprotective drugs, 39.8% received medium-dose histamine H2 blockers, and 20.4% received proton-pump inhibitors (PPIs). Anti-H. pylori antibody titers were positive in 43.7% of patients. The incidence of definitive gastric ulcers in this population was 0.97%. Ordered logistic regression analysis revealed that the odds ratio for the increase in the modified Lanza score was 0.20 for medium-dose histamine H2 blockers and 0.09 for PPIs.The incidence of postoperative definitive gastric ulcers in Japanese patients receiving ≤100 mg enteric-coated aspirin was 0.97%. The use of PPIs and histamine H(2) blockers may prevent aspirin-induced gastric injury in such patients.

The influence of ischemic zone size and hemodynamics on the reperfusion-induced arrhythmia in the anesthetized rat heart was examined. The heart was subjected to regional ischemia for 4 min by the occlusion of LAD followed by reperfusion for 7 min. After the reperfusion, 64% of the rats died due to irreversible VF. The size of the ischemic zone, the increase in heart rate during ischemia and the incidence of ischemic arrhythmia (VPBs and/or VT) of the animals that died after the reperfusion were significantly greater or higher than those of the surviving animals. There were positive correlations between the size of the ischemic zone and the increase of heart rate during ischemia and the incidence of ischemic arrhythmia. These results indicate that the size of the ischemic zone is a main factor that determines the degree of reperfusion-induced arrhythmia and also contributes to the increase in heart rate and the occurrence of arrhythmia during ischemia. Therefore, in addition to monitoring the blood pressure, heart rate and electrocardiogram, measurement of the size of the ischemic zone is essential for the evaluation of drug effects on reperfusion-induced arrhythmia using this animal model.

The purpose of this study was to assess the clinical features and characteristics of the blood flow in uterine vascular abnormalities using ultrasound and magnetic resonance imaging (MRI). A total of 17 women were diagnosed with uterine vascular abnormalities by ultrasound. The clinical characteristics of the patients and the distribution and waveform of the intrauterine vessels were examined using transvaginal gray-scale and Doppler ultrasonography, spin-echo MRI, and MR angiography. The average age of the 17 subjects was 44.3 years, and 5 were postmenopausal women. The number of pregnancies and deliveries was 2.0 and 1.7, respectively. Of the 17 subjects, 7 had a moderate or severe grade of dysmenorrhea and 7 had a history of vascular disease. In all subjects, vaginal ultrasound demonstrated tubular or numerous tortuous anechoic areas in the uterine wall, and Doppler ultrasound showed that the tubular or numerous dilated tortuous vessels had an atypical wave flow, unlike that of an artery or a vein. The distribution of displayed flow varied, and the waveforms of the Doppler ultrasound displayed three patterns. The averages of the pulse Doppler flow indices showed low impedance in the abnormal uterine vessel and the uterine artery, especially in cases of true arteriovenous malformations. MR angiography demonstrated distinct, tortuous, and coiled vascular channels in the pelvis during and just after the arterial phase. Characterization of the clinical features of uterine vascular abnormalities is considered to be valuable for obstetricians and gynecologists.

The study aim was to assess the long-term durability of mitral valve (MV) repair for MV prolapse using echo-Doppler evaluation.Between July 1991 and December 2006, MV repair was performed in 603 patients with nonischemic, severe mitral regurgitation (MR). A subset of 517 patients (mean age 56.3 +/- 12.0 years) with MR caused by leaflet prolapse resulting from degeneration of the MV was subsequently investigated. The main techniques used for MV repair included chordal replacement with ePTFE sutures for 274 of 278 patients with anterior leaflet (AL) prolapse, and leaflet resection for 239 patients with posterior leaflet (PL) prolapse. A prosthetic ring or band was used for annuloplasty in 340 patients, and a band of autologous pericardium in 161; no ring or band was used in the remaining 16 cases. Postoperative serial transthoracic echocardiography was performed for all hospital survivors before discharge, and on at least one occasion after discharge in 507 patients. Echocardiographic follow up was available for up to 15 years (mean 4.4 +/- 3.6 years). Residual MR flow detected by color Doppler echocardiography was classified according to the maximum regurgitant jet area (MRA).The 30-day mortality was 0.57% (three deaths). There were 21 late deaths and 22 reoperations (five of which were re-repair for hemolysis). Kaplan-Meier survival and freedom from reoperation at 14 years were 79.0 +/- 6.0% and 74.5 +/- 9.6%, respectively. Estimates of freedom from severe MR (MRAor = 7.0 cm2) at five, 10 and 14 years were 94.2 +/- 1.5%, 82.8 +/- 3.6% and 77.5 +/- 5.5%, respectively. Freedom from severe MR at 14 years for 239 patients with isolated PL prolapse was 98.4 +/- 1.6%.Echocardiographic follow up of MV repair for MV prolapse demonstrates good long-term results. In particular, the results of MV repair for isolated PL prolapse were excellent.

Dehiscence or aortic valve commissural tear is a rare cause of acute aortic regurgitation (AR). We report a case of aortic valve commissural dehiscence with progressive AR and aortic root dilatation that was successfully repaired with aortic root and ascending aortic replacements. Clinical Summary A 67-year-old man was admitted to the Sakakibara Heart Institute with new onset of exertional precordial pain. His electrocardiogram and cardiac enzymes were normal. Contrast-enhanced computed tomography showed a small pericardial effusion but did not reveal aortic dissection. A transthoracic echocardiogram showed mild AR with no dilatation of the cardiac chamber. Furthermore, a flap or intimal tear of the proximal aorta was absent on transthoracic echocardiography. Because the patient had a history of paroxysmal atrial fibrillation, an antiarrhythmic drug was prescribed before discharge. After 1 month, he was readmitted to the Sakakibara Heart Institute because of the progression of dyspnea on exertion. He had a new diastolic murmur and a systolic murmur. Chest x-rays revealed pulmonary congestion. Transthoracic echocardiography demonstrated severe AR and moderate mitral regurgitation with dilatation of the left ventricle. Computed tomography showed aneurysmal enlargement of the ascending aorta with aortic root dilatation (ascending aorta, 47 mm; sinotubular junction, 44 mm; sinus of Valsalva, 44 mm); however, there was no evidence of aortic dissection. Transesophageal echocardiography was performedto assess the cause of AR. Transesophageal echocardiography revealed a prolapse of both the right and left coronary cusps (Figure 1) with no intimal flap in the ascending aorta. Surgery was planned after medical control of the patient’s heart failure. Amediansternotomywasperformed.Whenthepericardiumwas opened,bloodyserouseffusionwas observed.Cardiopulmonary bypass was performed with ascending aortic and bicaval venous cannulations. Bilateral pulmonary vein isolation with radiofrequency ablation was done before cardiac arrest. After aortic clamp and cardiac arrest, mitral annuloplasty with a semi-rigid ring (size, 28 mm) was performed. The body temperature was decreased to 25C, systemic perfusion was temporarily arrested, and retrograde cerebral perfusion was started. The ascending aorta was resected and replaced with a 24-mm knitted Dacron graft (Hemashield Gold, Boston Scientific, Natick, Mass) with 1 branch. After the completion of distal aortic anastomosis, systemic perfusion through the side branch of the graft was resumed. There was no dissection or intramural hematoma in the ascending aorta. There was a dehiscence of the commissure between the right and left coronary cusps of the aortic valve (Figure 2). The valve leaflets were slightly atherosclerotic but almost intact, and the aortic wall was normal. We performed aortic root replacement with a commercially available composite valved conduit (23‐26 mm; Carboseal, CarboMedics, Austin, Tex). Total cardiopulmonary bypass time was 188 minutes. The postoperative course was uneventful, and no neurologic deficit occurred.