白石 学

Transplantation of bone marrow mesenchymal stromal cells (MSCs) is an emerging treatment for heart failure. We have reported that epicardial placement of MSC-sheets generated using temperature-responsive dishes markedly increases donor MSC survival and augments therapeutic effects in an acute myocardial infarction (MI) model, compared to intramyocardial (IM) injection. This study aims to expand this knowledge for the treatment of ischemic cardiomyopathy, which is likely to be more difficult to treat due to mature fibrosis and chronically stressed myocardium. Four weeks after MI, rats underwent either epicardial MSC-sheet placement, IM MSC injection, or sham treatment. At day 28 after treatment, the cell-sheet group showed augmented cardiac function improvement, which was associated with over 11-fold increased donor cell survival at both days 3 and 28 compared to IM injection. Moreover, the cell-sheet group showed improved myocardial repair, in conjunction with amplified upregulation of a group of reparative factors. Furthermore, by comparing with our own previous data, this study highlighted similar dynamics and behavior of epicardially placed MSCs in acute and chronic stages after MI, while the acute-phase myocardium may be more responsive to the stimuli from donor MSCs. These proof-of-concept data encourage further development of the MSC-sheet therapy for ischemic cardiomyopathy toward clinical application.

Atrioesophageal fistula (AEF) is a potentially lethal complication of catheter radiofrequency ablation for atrial fibrillation. A 49-year-old man with paroxysmal atrial fibrillation who underwent catheter ablation around the pulmonary vein was admitted 31 days after the procedure, suffering seizures and fever. Magnetic resonance imaging of the brain showed ischemia and multiple lesions of acute infarction in the right occipital lobe of the cerebrum. Computed tomography (CT) of the chest showed a small accumulation of air between the posterior left atrium and the esophagus, suggesting an AEF. Endoscopic snaring of the esophageal mucosa, repeated a few times, supported by nil by mouth and antibiotic therapy, resulted in improvement of his condition with no recurrence of symptoms. Subsequent chest CT scans confirmed disappearance of the leaked air and the patient was discharged home 45 days after admission with no neurological compromise.

Objective: Waffle procedure, a small grid-like incision of epicardium, is a surgical technique for constrictive pericarditis with epicardial thickening. Yet evidences to endorse this approach for improved outcomes are lacking. The aim of this study is to elucidate better surgical treatment strategy for constrictive pericarditis with epicardial thickening. Methods: Twenty-five patients (mean 64.1 years) who underwent pericardiectomy for constrictive pericarditis between January 1992 and July 2012 were included in this study and were classified into two groups according to the procedure they received single total pericardiectomy (Group A, n = 17) and total pericardiectomy with the Waffle procedure (Group B, n = 8). Early and mid-term outcomes were analyzed for each group. Results: No major postoperative complications or all-cause deaths at 30 days were observed in each group. Upon discharge, postoperative echocardiography showed statistically significant increase of left ventricular end-diastolic volume (from 76.6 ± 30.3 to 91.0 ± 27.3 ml p &lt  0.02) and systolic volume (from 44.4 ± 19.1 to 54.5 ± 17.3 ml p &lt  0.05) in Group B than those in Group A. The 5-year cardiac event-free rate was similar between groups [83.6 ± 10.8 % for group A and 83.3 ± 15.2 % for group B (p = NS)] as well as the mean value of NYHA classification for each at the mid-term periods (1.5 for Group A and 1.3 for Group B). Conclusion: Waffle procedure improved echocardiographic elements of diastolic function of patients with epicardial thickening more than did total pericardiectomy without additional compromises.

A secondary aortoenteric fistula is a relatively rare complication of abdominal aortic reconstruction. The clinical manifestation of aortoenteric fistula is usually upper gastrointestinal bleeding. We report a patient who developed acute aortic occlusion following chronic cellulitis, which is an uncommon finding. A 50-year-old man with a history of aortobifemoral bypass grafting was admitted for tiredness, fever and swelling of his right leg. On the 40th day of admission, he developed acute aortic occlusion. Computed tomography revealed right distal aortic graft occlusion and the presence of gas surrounding the graft. Gastroduodenoscopy showed an underlying Dacron graft consistent with an aortoenteric fistula in the third part of the duodenum. We excised the infected graft and reconstructed the abdominal aorta with a new prosthetic graft in situ, which was wrapped with the vascularized pedicle of the omentum. The duodenal defect was repaired with segmental duodenal resection and end-to-end anastomosis. The patient recovered well after surgical management and has remained in good condition for 2 years without developing any signs of recurrence of infection.

A 65-year-old woman with exercise-related dyspnea was admitted to our hospital. Transthoracic echocardiography demonstrated a large anomalous papillary muscle that originated from the posterior wall of the left ventricle and severe mitral valve regurgitation in systole. Cleft suture, 5-0 polytetrafluoroethylene sutures from a single papillary muscle to the anterior commissure leaflet (AC), 5-0 polypropylene sutures between AC and A1, and between A1 and A2, the double-orifice technique, and ring plasty with 32-mm semi-rigid ring was performed. Postoperative echocardiography showed an improvement in severe mitral valve regurgitation. At the 2-month follow-up, the patient was in good health. In the present case, the elderly patient with an isolated parachute mitral valve but without any other cardiac anomaly and presenting with mitral valve regurgitation is extremely rare. This case of mitral valvuloplasty for a parachute mitral valve with a single papillary muscle in an elderly woman has not been reported before.

Pulmonary artery aneurysm (PAA) is generally a rare lesion, and there is no definitive approach for it. We report the case of a 45-year-old man who was admitted for the evaluation of dyspnea. In childhood, he had been diagnosed with PAA with congenital pulmonary valve stenosis and regurgitation, and he had a percutaneous transvenous pulmonary valve commissurotomy. Transthoracic echocardiogram showed dilatation of the right atrium and right ventricle, with right ventricular hypertrophy. There was severe pulmonary valve regurgitation, and the main pulmonary artery was dilated to 68 mm in diameter. From the surgical findings, the left leaflet of pulmonary valve was torn from commissure with failure to coapt with the other leaflet. After direct sutures of edges of the left leaflet, a nearly normal valvular competence was restored. The PAA was repaired with a Y-shaped 24 x 12 mm Dacron graft replacement. The postoperative course was uneventful, and the patient was discharged.

We report a case of an apico-aortic bioprothesis-valved conduit for a 70-year-old-woman with symptomatic, severe aortic stenosis and severe calcification of the ascending aorta. She had a history of mastectomy and radiation therapy for breast cancer and was suffering from radiodermatitis and chronic thoracic wall infection. Transthoracic echocardiography showed severe aortic valve stenosis with heavy calcification and high aortic valve pressure gradients. In patients with a chronically infected thoracic wall, median sternotomy is considered to be a high risk procedure, resulting in postoperative mediastiniti; therefore, we applied a technique in which we used an apico-aortic conduit via posterolateral thoracotomy. We underwent apico-aortic bypass with a hand-made composite graft: 19-mm bioprosthetic valve and a 22-mm woven polyester vascular graft. The surgical intervention successfully decreased pressure gradient across the aortic valve, also separating an incision from chronic infection allowed us to avoid postoperative mediastinitis. The patient had remained in good condition for 15 months without developing any complications.

A 73-year old man underwent transthoracic and transoesophageal echocardiography and computed tomography, which revealed what appeared to be an asymptomatic primary mobile tumour located in the right atrium. During surgery, the mass was found to be associated with the right atrial septum and was subsequently resected. Histopathology of the mass revealed a cardiac varix with phleboliths. The patient had an uneventful postoperative course and no signs of recurrence at the 10-month follow-up.

A 46-year-old man with a medical history notable only for schizophrenia was admitted to hospital with complaints of general fatigue and high fever. Transthoracic echocardiography on day 6 after admission demonstrated a large vegetation (17 mm) on the anterior leaflet of the mitral valve with mild regurgitation and mild aortic regurgitation. The patient also complained of abdominal pain. Abdominal computed tomography showed a remarkable enlargement of the superior mesenteric artery aneurysm (SMAA). An excision of the SMAA and double valve replacement was performed, and the patient was administered a six-week course of intravenous antibiotic therapy. (C) 2011 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.