Objectives: The aim of this study was to investigate the yearly changes in scores of medical students’ written examinations in physiology and to find evidence in these scores for the lowering of academic performance levels of medical students in Japan after the number of medical students was increased.
Methods: With the scores of examinations in physiology from 2002 through 2012, the mean scores, standard deviations（SD）, the mean±SD, the numbers of students, the numbers of failing students, and the percentages of failing students were examined.
Results: The scores of examinations in physiology decreased significantly after the number of medical students was increased.
Conclusion: One cause of the lowering of academic performance levels of medical students in Japan is the increase in the number of medical students.

Persistent fifth aortic arch has been thought to be rare but often relevant to systemic circulation, however when it connects to the pulmonary artery (PA) in pulmonary atresia, it may be the sole arterial supply to the lung. This report describes a case of rare arch anomaly including right aortic arch (RAA), PA sling in conjunction with persistent left fifth aortic arch (PLFAA) and left subclavian artery arising from the left fourth arch. The tetralogy of Fallot, pulmonary atresia, and total anomalous of pulmonary venous connection (cardiac) were also diagnosed. A neonate was referred to our hospital for surgical treatment of cardiac and extracardiac anomalies. Persistent fifth aortic arch connecting with pulmonary artery was initially thought to be patent ductus arteriosus (PDA), so prostaglandin E 1 administration was commenced. He underwent emergency colostomy for anal atresia. Subepiglottic tracheal stenosis was diagnosed at initiation of anesthesia. At age 1-month-old, he required systemic to pulmonary shunt and reimplantation of left pulmonary artery through a median sternotomy using extracorporeal circulation. At the operation the PDA was divided and oversewn, and the wall structure was the same as that of a normal artery. The left pulmonary artery behind trachea was dissected and we then cut away and reimplanted to pulmonary trunk. Tracheostomy was performed at the age of two months. With the technical development of diagnostic imaging, the morphological features of arch anomaly were clearly demonstrated, but some understanding of embryological aspects are still required for diagnosis.

Isolated unilateral absence of the pulmonary artery without any intracardiac anomaly is a rare congenital cardiovascular disorder. We performed a successful anatomical repair after systemic-to-pulmonary shunt. The patient was a 1-day-old boy who was transferred to our institution because of continuous murmur. Cardiac echography revealed anomalous origin of the right pulmonary artery from the ascending aorta (AORPA). This aorto-right pulmonary arterial blood flow, however, disappeared in the following 2 days. We altered the diagnosis to right unilateral absence of pulmonary artery (UAPA) from AORPA. A right systemic-to-pulmonary shunt using a 3 mm polytetrafluoroethylene (PTFE) graft was placed, aiming for growth of the right pulmonary artery at the age of 8 days. Forty days after the initial surgery, he underwent a definitive procedure. The right pulmonary artery was anatomically reconstructed with an 8-mm PTFE graft. He was discharged in excellent condition on postoperative day 41. Cardiac catheterization, 1 year later, showed the surgically created right pulmonary artery was patent. A pulmonary perfusion scintigraphy showed satisfactory blood distribution in the right lung.

The supracardiac type is the most common total anomalous pulmonary venous connection (TAPVC) and is thought to be relatively rarely accompanied by pulmonary venous obstruction. An ascending vertical vein usually passes anterior to the left pulmonary artery, connecting to the brachiocephalic vein without obstruction. Now we report two cases in which the vertical vein passed between the left pulmonary artery and left bronchus with severe pulmonary vein obstruction in neonate. The cases are 12-day and 8-day males both of which were diagnosed mainly by UCT and underwent a succesful emergency operation. The former case with more severe pulmonary congestion than the later, had slower improvement of respiratory function and mild pulmonary hypertension after operation. The ascending vertical veins of both cases are compressed between left pulmonary artery and left main bronchus and then the pulmonary venous obstruction will appear and increase pulmonary hypertension. Resultant distention of the pulmonary artery will cause greater compression of the vertical vein. This will create a “hemodynamic vise.” For these cases, an earlier operation is required at the point of post-operative recovery.

Giant left atrium (LA) in association with mitral valve disease is a significant risk factor for mortality and morbidity. It may cause obstruction of the bronchus, pulmonary artery, inferior vena caval orifice, or left ventricle, and has also required prolonged hospital stay. We describe our experience of left atrial reduction by means of circular LA resection concomitant with mitral valve plasty in 2 children with severe mitral regurgitation (MR) and giant LA. Case 1 was a 1-year-old boy, who had severe MR and giant LA, presenting with left bronchial obstruction. He underwent mitral valve plasty and circular LA resection. His LA volume, which was calculated using enhanced chest CT examination, was decreased by 23% postoperatively, comparing that before the operation. The cardiothoracic ratio on chest X-ray changed from 60% to 49%, and his sequential symptoms from giant LA disappeared. His postoperative course was uneventful and he was discharged on postoperative day 21. Case 2 was a 12-year-old girl with severe MR and giant LA. Her LA together with the sternum and spine compressed the right atrium and caused right heart failure. She underwent mitral valve plasty and circular LA resection. Her LA volume was decreased by preoperative 22%. Cardiothoracic ratio on chest X-ray changed from 63% to 57%. Her sequential symptoms from giant LA disappeared. Her postoperative course was uneventful and she was discharged 28 days after the operation. The circular LA resection technique reduced LA volume effectively, and the patients became free of clinical symptoms. Even in children, this procedure should be indicated in selective cases who presented clinical symptoms caused by the expanded LA.

Continuous retrograde cerebral perfusion (CRCP) during hypothermic circulatory arrest is a useful adjunct for brain protection during aortic arch surgery. According to our experience, no correlation was observed between perfusion pressure and flow rate. Internal jugular vein valves can restrict the flow of CRCP. We performed a study of internal jugular valves, morphologically in autopsy specimens and functionally in clinical patients. Apparently good venous valves were observed in 18 out of 30 cases (60%) on the right side and in 10 out of 29 cases (34%) on the left side. Of 32 autopsy cases, all but one had venous valves at the venous angle. Angiography of the right brachiocephalic vein revealed internal jugular vein valves in only 15 of 38 patients (39%), and in 34 of the 38 patients (89%) some regurgitation of the valve was demonstrated. In 4 patients (11%), no regurgitation was observed. These results show that internal jugular vein valves can restrict the flow of CRCP in some cases and this may be one possible cause of the lack of correlation between perfusion pressure and flow rate.

Plasma concentrations of tumor necrosis factor α (TNFα), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were measured successively during and after open heart surgery (13 cases). Plasma concentrations of TNFα did not increase during surgery but increased gradually after the 1st operative day reached the maximum level at the 7th operative day (128±15pg/ml, which was a 3-fold increase compared with the previous value). Plasma concentrations of IL-1β remained at the previous level during surgery and increased only once at 6 hours after operation. Conversely, plasma concentrations of IL-6 increased dramatically during cardiopulmonary bypass (CPB) reaching a peak at the end of CPB (260±200pg/ml, which was a 15-fold increase over the previous value) and recovered to previous values rapidly thereafter. Plasma IL-6 concentrations changed rapidly during surgery, while plasma concentrations of TNFα and IL-1β did not increase sharply. This may indicate that IL-6 may play a role as a mediator of acute inflammatory reaction.

Thirteen cases of ruptured abdominal aortic aneurysm were treated during a period of 7 years and 5 months. In 6 cases, left thoracotomy was used before laparotomy to clamp the descending thoracic aorta. The merits and demerits of this method were evaluated in this study. It is useful for early improvement of cerebral and coronary circulation and prevention of sudden spurting hemorrhage, especially in cases with the previous laparotomies. On the other hand, this method has a shorter clamp time limit and requires much time in cases with pleural adhesions. It may increase the amount of operative bleeding and the incidence of postoperative respiratory insufficiency. It may also cause an intraoperative thoracic aortic dissection and rupture of thoracic aortic aneurysms if present. It is considered that this method is advantageous, but should be used only in selected cases.

We report the successful repair of impending rupture of a pseudoaneurysm of the brachiocephalic artery (BCA) in a 70-year-old man. He had undergone a mediastinal tumor resection through a median sternotomy in 1995. Pathological examination revealed non-Hodgkin's lymphoma. Two years later, he underwent radiation therapy of 65 Gray for metastasis to the supraclavicular lymph nodes. On January 18, 2000, plastic surgeons planned to perform a pectoralis major musculocutaneous flap to repair a radiation skin ulcer. During the operation, the BCA was lacerated, possibly in an area of radiation tissue damage. We performed a prosthetic graft (10-mm Gelseal^TM) replacement of the BCA. The right subclavian artery had to be ligated. Postoperative digital subtraction angiography (DSA) showed excellent reconstruction of the artery. Magnetic resonance angiography of the brain showed a deficit in the anterior communicating artery and stenosis of the posterior communicating artery, which indicated that the reconstruction procedure was reasonable. Seven months later, on August 18, 2000, the patient was transferred to our hospital because of swelling of the right neck and oozing from the previous cutaneous wound. CT scan and DSA demonstrated the presence of a pseudoaneurysm of the proximal anastomosis site, which required emergency surgery. Before this third sternotomy, a saphenous vein graft was interposed between both external carotid arteries. Removal of the prosthetic graft and resection of the pseudoaneurysm were performed under mild hypothermia and cardiopulmonary bypass with left common carotid arterial perfusion. Then, the wound was closed completely using a left pectoralis major musculocutaneous flap. The postoperative course was uneventful and DSA showed good patency of the graft and intracranial arteries. The patient was discharged without neurological complications. We conclude that prior reconstruction of the carotid artery is a safe and effective procedure for patients with aneurysmal changes in the BCA, especially in the case of re-operation.

Introduction: Recently, community-based medical education has become widespread in Japanese medical schools, but the current status is not clear on a national level. A second survey of community-based medical education at all Japanese medical schools was conducted. The first survey was done in 2011. Methods: Members of the Council made and distributed a questionnaire to medical schools in order to assess the situation of community-based medical education as of April 2014. Results: A total of eighty schools responded. The number of schools which had community medicine programs was seventy-eight. In the first survey, the number was seventy-three. Seventy-seven schools gave community-based clinical clerkships. Discussion: The number of medical schools that had curriculum about community medicine was more than indicated in the first survey. Further research about the contents or implementation system of community-based clerkships is needed.