Akihiko Yamauchi

Pre-administration of angiopoietin-1 followed by VEGF induces functional and mature vascular formation in a rabbit ischemic model

Angiopoietin‐1 (Ang1) and vascular endothelial growth factor (VEGF) play important roles in vascular formation and maturation, suggesting that the combination of these two would be a promising therapy for ischemia. However, it remains unclear what the best schedule of administration of these cytokines might be.

Hybrid treatment for aortic arch and proximal descending thoracic aneurysm: experience with stent grafting for second-stage elephant trunk repair

BACKGROUND Aortic aneurysm affecting the arch and proximal descending thoracic aorta may require a two-stage repair, which includes proximal elephant trunk graft placement and completion of descending thoracic aortic repair. The combination of open surgery and endovascular grafting may improve the morbidity and mortality of the patient population at risk. METHODS Between February 2001 and March 2007, 258 patients underwent thoracic aortic endovascular grafting at our institution, wherein 31 patients underwent a hybrid approach involving proximal arch repair and elephant trunk graft replacement, and endovascular completion procedures. All patients, who underwent combined endovascular and open procedures in the management of the aortic arch and proximal descending thoracic aortic aneurysms, were reviewed and analysed retrospectively. RESULTS The interval between the first and second stage ranged from 0 to 14 months with a mean interval of 3.1 months. Follow-up ranged from 0 to 70 months with a mean of 31 months. Technical success was achieved in all patients. The 1, 12, 36 and 60-month mortality rates were 6.4%, 16.5%, 26.7% and 26.7%, respectively. Caudal migration of the endograft occurred in three patients, who underwent conversion to open surgery. Two cases of paraparesis but no paraplegias or strokes were recorded. CONCLUSIONS Staged procedures using endovascular grafting in the treatment of the arch and proximal descending thoracic aneurysm may have the potential to reduce morbidity and mortality rates. Although long-term results are still pending, this early experience demonstrates the safety and early-term effectiveness of this hybrid approach, which consists both of endovascular and open surgical procedures.

Isolated cerebral perfusion for intraoperative cerebral malperfusion in type A aortic dissection.

Cerebral malperfusion due to expansion of a false lumen can occur acutely during aortic repair when retrograde femoral perfusion is initiated. We detected this catastrophe by a rapid decrease in regional cerebral oxygenation and successfully treated it by immediate isolation of the cerebral circulation from the systemic circulation. The surgical management, including the above technique, for this rare event is described.

Endovascular stent-grafting of anastomotic pseudoaneurysms following thoracic aortic surgery

PurposeAnastomotic pseudoaneurysm is a rare but life-threatening complication after thoracic aortic surgery. Endovascular stent-grafting is a less invasive treatment for thoracic aortic aneurysm; however, its clinical usefulness for anastomotic pseudoaneurysms following thoracic aortic surgery is unclear.MethodsA series of 12 anastomotic pseudoaneurysms in 10 patients, which occurred following thoracic aortic surgery, underwent endovascular stent-grafting in our university hospital. Eight emergent endovascular stent-grafting cases were included in this study. A hand-made stent-graft, reconstructed by suturing graft material to an endoskeleton of modified Gianturco Z stents, was used in all cases.ResultsThe delivery success rate was 91.7%, and the hospital mortality rate was 25.0%. Two cases were converted to open surgery during the postoperative phase because of a type I endoleak. Complete absorption or shrinkage of the anastomotic pseudoaneurysm was observed in seven of nine cases.ConclusionEndovascular stent-grafting for patients with anastomotic pseudoaneurysms of the thoracic aorta following thoracic aortic surgery has become a possible optimal treatment. However, long-term outcome remains unclear, and periodical follow-up is required.

Surgical resection of primary cardiac lymphoma presenting as a huge mass: report of two cases.

Primary cardiac lymphoma (PCL) is a rare malignancy that is sometimes diagnosed at later stages because it is not associated with specific symptoms. Although chemotherapy is the standard for treating PCL, the value of surgical resection is controversial. We describe two patients who were treated by surgical resection and chemotherapy. Case 1 is a 37-year-old man with a history of acute lymphocytic leukemia and shortness of breath, and Case 2 is a 70-year-old woman with general fatigue. Both of them were presented at hospital. In Case 2, arrhythmic syncope occurred and direct current cardioversion was performed. Echocardiography showed a massive tumor in the right atrium and disturbed hemodynamics in both cases. The restricted venous return was alleviated by emergency surgery. The pathology report indicated primary cardiac lymphoma that was regressed by post-operative chemotherapy. A massive PCL should be surgically resected to prevent sudden death.

A successfully treated case of blunt traumatic right coronary ostium rupture

Cardiac tamponade due to coronary artery rupture, as a consequence of blunt trauma, is a rare but usually fatal condition. We successfully obtained primary hemostasis with emergency room thoracotomy, followed by delayed definitive treatment of the ruptured right coronary artery ostium in a motor vehicle accident victim with multifocal hemorrhagic lesions. Survival of patients with the described serious trauma has not been reported, and we discuss herein our treatment strategy.

Extrapleural resection of lung metastasis in a patient with dense pleural adhesions using VATS

We report the case of a 78-year-old man with dense pleural adhesion who underwent a resection of a lung metastasis by video-assisted thoracic surgery (VATS) through an extrapleural approach. The approach for diagnosis and therapeutic wedge resection of a lung tumor by VATS is easier and safer than an intrapleural approach if the patient has dense pleural adhesions.

Premature atrial contraction as a predictor of postoperative atrial fibrillation

Background Postoperative atrial fibrillation occurs in 20%–60% of patients after cardiac surgery. Recently, premature atrial contraction has been considered an initiator of atrial fibrillation. This study evaluated whether the frequency of premature atrial contractions predicts the occurrence of postoperative atrial fibrillation. Methods The subjects of this study were 70 patients with no history of atrial fibrillation who had undergone a 24-h Holter electrocardiogram before off-pump coronary artery bypass. Their records were reviewed and postoperative electrocardiograms and telemetry strips were analyzed for postoperative atrial fibrillation. Results Postoperative atrial fibrillation was documented in 22 (31.4%) patients. The frequency of preoperative premature atrial contractions was significantly higher in the postoperative atrial fibrillation group (4128 ± 7186 vs. 69 ± 221 beats/24 h, p < 0.001). The incidence of postoperative atrial fibrillation increased with the frequency of preoperative premature atrial contractions which occurred in 60% of patients in the upper 50th percentile group of preoperative premature atrial contractions. Multivariate logistic regression analysis revealed the upper 50th percentile group of preoperative premature atrial contractions (odds ratio = 67; 95% confidence interval: 5.51–838; p = 0.001) to be an independent predictor of postoperative atrial fibrillation. Conclusion A high frequency of preoperative premature atrial contractions is a strong independent predictor of postoperative atrial fibrillation in off-pump coronary artery bypass.

Extended survival of a porcine mitral bioprosthesis for 23 years: Report of a case

Limited durability is the major drawback of bioprosthetic valves, few of which survive for as long as 20 years. We report herein the case of a patient we recently encountered in whom a bioprothesis lasted for 23 years. To our knowledge, this is only the second case of such long survival. The patient was a 56-year-old man who was urgently admitted to our hospital with acute mitral regurgitation, 23 years after undergoing mitral valve replacement with a porcine bioprosthesis. Acute leaflet tears were found to be the cause of the mitral incompetence and the xenograft was successfully replaced with a mechanical valve. We believe that when reoperation is thought to carry a low risk, prophylactic surgery might be justified, even in patients without symptoms.

Herniation of transverse colon into mediastinum after pedicled omental grafting for mediastinitis: report of a case

We describe a rare complication and the treating experience of it after pedicled omental grafting for mediastinitis. The patient was diagnosed as an acute mediastinitis soon after the total arch replacement was performed. A two-staged strategy to treat postoperative mediastinitis was scheduled, i.e., the setting up of a vacuum-assisted closure system until the improvement of inflammation followed by wound closure with pedicled omental grafting. The treatment for acute mediastinitis was successful and the patient followed a favorable postoperative course. During the follow-up, chest X-ray film suggested the gradual enlargement of mediastinum and CT showed the herniation of transverse colon into mediastinum. Surgical correction for the hernia was scheduled and performed successfully by the laparoscopic procedure to prevent a possible cardiac and pulmonary dysfunction.