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.