Uhito Yuasa

Changes in False Lumen After Transluminal Stent-Graft Placement in Aortic Dissections Six Years’ Experience

Background—Transluminal stent-graft placements (TSGPs) are a new, less invasive procedure now recognized as the choice for aortic disease repair. Treatment of aortic dissections with TSGPs has resulted in good early results, but the long-term results and changes in the false lumen have not been elucidated in detail. Methods and Results—TSGPs were performed in 49 patients with primary tears in their descending aortas, and the follow-up period ranged from 4 months to 6 years. The patients were divided into 32 acute-onset and 17 chronic dissections; of the acute-onset cases, there were 15 Stanford type A retrograde dissections. Periodic enhanced spiral CT was conducted after TSGP. The false lumen in the ascending aorta in 14 (93%) of the Stanford type A cases was obliterated completely within 3 months. The CT study was continued for >2 years for 17 acute-onset dissection and 11 chronic dissection patients. The average false lumen diameters of the proximal, middle, and distal descending aorta before treatment were 15.9, 16.2, and 15.6 mm in the acute-onset dissection group and 28.1, 25.2, and 21.0 mm in the chronic dissection group, respectively. The false lumen diameters 2 years after treatment were 3.0, 3.7, and 3.1 mm in the acute-onset dissection group and 10.6, 10.5, and 11.9 mm in the chronic dissection group, respectively. Two years after TSGPs, the false lumen of the thoracic aorta totally disappeared in 76% of the acute-onset dissection group and 36% of the chronic dissection group. No cases showed rupture after TSGP. Conclusions—Complete obliteration of the false lumen is more likely in acute-onset cases than in chronic cases.

Pulmonary leiomyosarcoma extending into left atrium or pulmonary trunk: complete resection with cardiopulmonary bypass☆☆☆★★★

Primary pulmonary leiomyosarcoma is a rare tumor. Few cases have been treated surgically because of its rapid invasion into the pulmonary trunk or heart and tendency toward massive intrapulmonary metastases. We report the cases of two patients with leiomyosarcoma originating in a pulmonary artery or vein that involved the pulmonary trunk or left atrium, both of whom underwent complete surgical resection with cardiopulmonary bypass (CPB). Since their operations, these patients have shown no evidence of recurrent tumor. PATIENT 1. A 72-year-old woman with persistent cough, chest pain, and hemoptysis was referred to our hospital for evaluation and treatment of presumed pulmonary thromboembolism. An angiogram revealed filling defects in the pulmonary trunk, absence of filling of the left main pulmonary artery, and decreased arterial filling in the left lung. A biopsy specimen was obtained from a tumor in the left main pulmonary artery by means of a suction catheter, and the pathologic diagnosis of sarcoma was made. Computed tomography disclosed a mass occluding the left main pulmonary artery and densely filling pulmonary artery branches. Median sternotomy was performed and CPB was applied. The left pulmonary veins were ligated and the left main pulmonary artery was incised. A large tumor completely filled the left main pulmonary artery. Extension of the incision into the pulmonary trunk disclosed that the tumor invaded its wall laterally on the left. The portion of tumor located in the left main pulmonary artery and pulmonary trunk, including the left main pulmonary artery and the left lateral wall of the trunk, was excised. Direct suture closure of the pulmonary trunk was carried out and CPB was terminated. The left main bronchus was transected and left pneumonectomy was completed. Fig. 1 shows the resected left lung and pulmonary artery. Tumor in the main pulmonary artery extended intraluminally into its branches. The tumor was diagnosed histologically with the aid of immunohistochemical stainFrom the Department of Thoracic and Cardiovascular Surgery, Mie University, School of Medicine, Tsu, Japan.

Coronary artery aneurysm in a patient with Marfan syndrome

True aneurysm of the coronary artery in Marfan syndrome is very rare. We present a patient with Marfan syndrome who had aneurysms from the ascending aorta to the thoracoabdominal aorta and a large aneurysm of the left main coronary artery after an original Bentall operation. Prosthetic graft replacement of total aorta, coronary artery bypass grafting, and removal of the aneurysm of the left main coronary artery were successfully performed.

Stent-graft placement combined with percutaneous fenestration for the treatment of aortic dissection in a patient at risk of developing renal ischemia

A 51-year-old man, suffering from an aortic dissection with the entry tear in the descending thoracic aorta, underwent replacement of the ascending aorta and aortic arch with resection of the entry tear. Although the false lumen of the descending thoracic aorta was thrombosed after surgery, redissection developed in the descending aorta 2 months later. Percutaneous fenestration was performed before stent-grafting because it was judged that there was a significant risk of left renal ischemia. Entry closure with a stent-graft was performed successfully and no renal ischemia developed. The patient is doing well at 1 year after the procedure.

Upside down use of Gore Excluder or Cook Zenith Legs

PurposeEndovascular aneurysm repair is becoming increasingly popular. This technical note describes the usefulness of the upside-down technique of Gore Excluder or Cook Zenith legs.MethodsFour patients with iliac or abdominal aortic aneurysms were treated. Three patients with isolated iliac artery aneurysms and one patient with an abdominal aortic aneurysm, in which the neck diameters were unfit for commercially available stent-grafts, were treated using an Excluder or a Zenith leg in an upside-down technique.ResultsThe aneurysms were completely excluded and no endoleak occurred. There were no serious adverse events.ConclusionsThe upside-down technique using an Excluder leg or a Zenith leg is both feasible and effective.

Coronary artery bypass grafting after radiation therapy for lung cancer

Radiation therapy has been a common treatment modality for many malignant tumors, including lung cancer. Coronary artery disease can be an adverse effect of chest irradiation as well as other major coronary risk factors. Coronary artery bypass grafting in such patients is difficult due to the presence of extensive radiation-induced mediastinal fibrosis. Here, we describe a successful case of surgical treatment for left main of coronary artery occlusion after radiation therapy for advanced lung cancer.

Modulation of Vascular Smooth Muscle Contraction by Calponin Phosphorylation

Calponin is an abundant thin filament-associated smooth muscle protein that has been implicated in the modulation of smooth muscle contraction. Recently, we found that smooth muscle calponin is an excellent substrate for protein kinase C and that phosphorylation reduced the binding of calponin to F-actin and tropomyosin. We found that Thr184 is the preferred site of phosphorylation and is functionally the most important of the sites phosphorylated by protein kinase C in smooth muscle calponin. We have demonstrated that calponin can be rapidly dephosphorylated by type lδ protein phosphatase, just as the 20kDa light chain in intact myosin can be dephosphorylated in vitro. We investigated calponin phosphorylation during endothelin-1 or phorbol 12,13-dibutylate (PDBu) stimulation of intact strips of porcine coronary artery. Stimulation by endothelin-1 or PDBu resulted in a significant increase of 32P incorporation into the calponin in association with the development of force. These results suggest that calponin phosphorylation by protein kinase C plays a potential role in the modulation of smooth muscle contraction by agonists.

Regulation of Smooth Muscle Contraction by Calponin Phosphorylation and Dephosphorylation

Calponin is a thin filament-associated smooth muscle protein that has been implicated to play a role in the regulation of smooth muscle. It inhibits actomyosin ATPase but the capacity for such inhibition is lost upon phosphorylation of calponin by protein kinase C. Thus, it seems possible that phosphorylation of calponin might modulate the contraction of smooth muscle. The objective of the present investigation was to determine whether calponin is phosphorylated by protein kinase C in intact smooth muscle in response to a vasoconstrictor and whether such phosphorylation is of functional significance with respect to the contraction of smooth muscle. Endothelin-1 and phorbol 12, 13-dibutyrate (PDBu) caused 2.3-fold and 2.6-fold increases, respectively, in tthe extent of phosphorylation of calponin during contraction of porcine coronary artery. However, high levels of KCl were ineffective despite development of an identical contractile force. These results suggest that the phosphorylation of calponin in vivo by protein kinase C might play an important role in the contraction of smooth muscle that occurs in response to endothelin-1 and PDBu.

One-Stage Repair of Salmonella enteritidis-Infected Infrarenal Aortic Aneurysm A Case Report

A sixty-three-year-old man was admitted with systemic sepsis, but he was in a hemody namically stable situation and found to have a contained rupture of an infrarenal aortic aneurysm, which was infected with Salmonella enteritidis. An abdominal plain film revealed a gas shadow forming a ring in the midabdomen. Computed tomography (CT) showed a contained rupture of an infrarenal aortic aneurysm with a gas formation in the retroperitoneum. An emergent extra-anatomic bypass from the ascending aorta to (continued on next page) (Abstract continued) the femoral arteries was performed. The retroperitoneal phlegmon and hematoma that contained a large pseudoaneurysm were removed through a separate incision. A CT obtained after surgery showed gas-containing fluid collections in the retroperitoneum and these were followed up by means of CT. Eight months after surgery, the fluid collec tions had resolved. Aggressive surgical treatment and antibiotic therapy have resulted in a successful outcome.