Current topics in surgery for multiple ventricular septal defects.

In this review article, we describe several topics, including the sandwich technique, the transatrial re-endocardialization technique, the limited apical left ventriculotomy approach and device closure. The sandwich technique was introduced for the closure of muscular ventricular septal defects (VSD) by sandwiching the septum between two felt patches placed in the left and right ventricle. This technique requires neither the transection of muscular trabeculae nor ventriculotomy. Although the sandwich technique has resulted in the improvement of surgical outcomes, cases of postoperative cardiac dysfunction have been reported. Multiple smaller VSDs have been closed with transatrial re-endocardialization. Septal dysfunction may be avoided through this technique, in which the septal trabeculae are approximated in two layers of superficial, endocardial running sutures. Recently, a number of reports have recommended a limited apical left ventriculotomy approach. With this technique, a much shorter incision of around 1 cm at the apex of the left ventricle may be sufficient for achieving the complete closure of apical muscular VSDs. The transcatheter or perventricular device closure of muscular VSDs has increasingly been performed with good results. Although favorable early and mid-term results of device closure have been reported, this method is not always safer or less invasive than surgical closure. Long-term evaluations should be performed to determine whether the right and left ventricular functions are affected by treatment with relatively large devices in the heart.

Spontaneous Hemothorax Caused by Pulmonary Micro-Venous Hemangioma.

Various etiologies of spontaneous hemothorax have been reported, though the cause remains unidentified in some patients despite an exploratory thoracotomy. We report on an 89-year-old man with spontaneous hemothorax resolved by partial resection of the lung using complete video-assisted thoracoscopic surgery. The histopathologic findings revealed a ruptured micro-venous hemangioma located just below the bleeding visceral pleura. To the best of our knowledge, this is the first report of spontaneous hemothorax caused by a pulmonary micro-venous hemangioma.

Critical contribution of MCL-1 in EMT-associated chemo-resistance in A549 non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is one of the leading causes of death in all lung cancer patients due to its metastatic spread. Even though cisplatin treatment after surgical resection of the primary tumor has been established as a standard chemotherapy for residual disease including metastatic spread, NSCLC often acquires a resistance against chemotherapy, and metastatic disease is often observed. Amongst many potential mechanisms, epithelial-to-mesenchymal transition (EMT) has been considered as an important process in acquiring both metastatic spread and chemo-resistance of NSCLC. In this study, we identified MCL-1 as a critical molecule for chemo-resistance in A549 cells associated with TGF-ß-induced EMT. Importantly, downregulation of MCL-1 by siRNA or inhibition of MCL-1 with pan-BCL2 inhibitor to inhibit MCL-1 was able to overcome the EMT-associated chemo-resistance in A549 cells. Collectively, MCL-1 can be a new therapeutic target for overcoming EMT-associated chemo-resistance in NSCLC patients in the context of post-operative chemotherapies.

Current topics in surgery for isolated total anomalous pulmonary venous connection.

Surgical correction of total anomalous pulmonary venous connection (TAPVC) remains a challenge, with reported early mortality rates of up to 20%. In this review article, we describe several topics, including surgery for neonates, diagnoses with multidetector computed tomography (MDCT), and primary sutureless repair. Several studies have reported mortality rates of around 10%, and demonstrated unchanged hospital mortality in neonates, despite improvement of the overall mortality of cohorts including older patients. Previous reports identified a low body weight at the time of the operation, preoperative pulmonary venous obstruction (PVO), and a prolonged cardiopulmonary bypass time as risk factors for hospital mortality. With the development of new technologies, MDCT has become a good diagnostic modality for use in the pre- and post-operative evaluation. MDCT delineates the drainage site of the vertical vein and the atypical vessel into the systemic vein, and it can also evaluate the existence of obstruction in the vertical vein. Following favorable experiences with post-repair PVO, the indications for sutureless repair as a primary operation have been expanded for infants, including those at risk of developing PVO after the repair of TAPVC. Primary sutureless repair has proven especially useful for difficult patient groups, such as those with congenital PVO, infracardiac TAPVC with small pulmonary veins, or mixed-type TAPVC.

Rare lipomatous tumor of the posterior mediastinum in children.

The mediastinum is a unique anatomic area containing various structures and pluripotent cells, which allow for the development of a range of tumors. We report two pediatric cases of a lipomatous tumor of the posterior mediastinum. Complete surgical excision of the mass in each was achieved through a lateral thoracotomy. Histopathologic findings showed a lipoma in one case and a lipoblastoma in the other. A lipomatous tumor in the posterior mediastinum is extremely rare and preoperative diagnosis is difficult. When an operative plan is being considered, the presence of a potentially malignant tumor should be kept in mind.

[Endovascular stent-graft insertion followed by resection of a locally-advanced lung tumor that invaded the thoracic aorta].

A 52-year-old man with fever and dyspnea was admitted to our hospital. Chest computed tomography showed a mass measuring 3.5×3.0 cm in the S(1+2) segment of the left lung with involvement of the aorta. Although cytological examination using broncho fiberscopy did not show any malignancy, we suspected the mass to be T4N0M0 lung cancer. The tumor was diagnosed as having invaded the aorta using intravascular ultrasound. First, an endovascular graft was inserted, and then, a left upper lobectomy with resection of the infiltrated aortic wall was performed without cardiopulmonary bypass. The patient had an uneventful recovery without any complications. Pathological examination revealed the tumor to be a large-cell carcinoma. We think that an aortic endograft can be useful for resection of an infiltrated aortic wall, although further studies are necessary.

Management of pulmonary venous obstruction.

Although improved surgical techniques have led to significantly better outcomes of surgery for total anomalous pulmonary venous connection, the risk of progressive pulmonary venous obstruction continues to be a clinical problem. Both obstructed total anomalous pulmonary venous connection and post-repair pulmonary venous obstruction are associated with a significant risk of recurrent obstruction or death, requiring reoperation for stenosis. In general, side to side anastomosis of the pulmonary venous confluence to the functional left atrium has been performed for supracardiac and infracardiac total anomalous pulmonary venous connection. Repair of total anomalous pulmonary venous connection to the coronary sinus invariably involved unroofing the coronary sinus, followed by pericardial patch closure of the atrial septal defect. Recently, sutureless technique has been adopted as the primary operation for the subgroups of patients that are thought to be at high risk for post-repair pulmonary venous obstruction, such as those with total anomalous pulmonary venous connection associated with right isomerism, infracardiac total anomalous pulmonary venous connection with small individual pulmonary veins, or mixed-type total anomalous pulmonary venous connection. Because the sutureless technique does not require direct anastomosis to the confluence, aggressive resection of the obstructed pulmonary venous tissue can be achieved, and surgically induced distortion of the suture line can be avoided, which may help to prevent subsequent pulmonary venous obstruction. Conventional management strategies for recurrent pulmonary venous obstruction have typically been associated with poor outcomes. Recent reports have supported the use of the sutureless technique to treat post-repair pulmonary venous obstruction.

[Immunoglobulin G4-related inflammatory pseudotumor of the lung].

A 61-year-old man was pointed out a solitary nodule located in the left lung (S9) measuring 18 × 29 mm in size along with lymphadenopathy by chest computed tomography (CT). Positron emission tomography( PET) scan showed a positive sign corresponding to the nodule[ standardized uptake value (SUV) max 5.8]. No diagnostic material was obtained from the transbronchial tumor biopsy, since it was difficult to rule out malignancy, surgical biopsy was performed with sampling of mediastinal lymph nodes. Histopathological examination showed marked infiltration of inflammatory cells, many of which were demonstrated to be immunoglobulin (Ig) G4-positive plasma cells by immunohistochemical staining. Hence, IgG4-related inflammatory pseudotumor of the lung was diagnosed.

Complete port-accessed lobectomy by the muscle-sparing method.

We report the case of a 53-year-old woman who underwent complete port-accessed middle lobectomy by a new technique that preserves all muscles, including the extracostal and intercostal muscles. The operation was performed by using only thoracovideoscopy, and the resected lobe was withdrawn in a pouch through a subxiphoid incision through the substernal route. This complete port-accessed lobectomy is a new technique and is thought to be less invasive than video-assisted lobectomy with minithoracotomy.