Riichiro Toda

Operation for adult patent ductus arteriosus using cardiopulmonary bypass.

BACKGROUND Surgical repair of adult patent ductus arteriosus is more hazardous than when performed on young patients. METHODS Nine adult patent ductus arteriosus patients underwent surgical repair between January 1986 and December 1998. There were 3 male and 6 female patients (mean age 55.0 years). The ratio of pulmonary blood flow to systemic flow was 2.40 +/- 0.95, and pulmonary arterial pressure was 56.0 +/- 26.4 mm Hg. The operation was performed using transpulmonary approach under total cardiopulmonary bypass. Balloon occlusion method was also utilized. RESULTS Direct closure was made in 5 and patch closure in 4 patients. Cardiopulmonary bypass and balloon occlusion were safely established. Cardioplegic arrest was not required in the 2 most recent patients. No operative death has occurred. Pulmonary arterial systolic pressure decreased to 35.3 +/- 6.6 mm Hg at 6 months after operation. The mean follow-up period for all patients is 55 months. To date, neither recannalization of the ductus nor pseudoaneurysm has been recognized. CONCLUSIONS Cardiopulmonary bypass with balloon occlusion provides a safe operation for adult patients with complicated patent ductus arteriosus.

Effect of a neutrophil elastase inhibitor (ONO-5046 Na) on ischemia/reperfusion injury using the left-sided heterotopic canine heart transplantation model

BACKGROUND Ischemia/reperfusion injury is a major cause of transplanted heart dysfunction. Several reports have demonstrated that polymorphonuclear neutrophil (PMN) elastase derived from the activated neutrophils might play an important role in this injury. Herein, we investigated the protective effects of PMN elastase inhibitor (ONO-5046 Na) on ischemia/reperfusion injury using a left-sided canine heterotopic heart transplantation model. METHODS We used 10 pairs of adult beagle dogs. The donor heart was transplanted heterotopically into the left thoracic cavity of the recipient without cardiopulmonary bypass. A bolus of ONO-5046 Na (10 mg/kg) was introduced intravenously to 5 recipients (group II) at 15 minutes before reperfusion and was followed by continuous infusion (10 mg/kg per hour) for 180 minutes. Five dogs (group I) did not receive ONO-5046 Na and thus served as a control. After reperfusion, we evaluated transplanted heart function and obtained blood samples from the coronary sinus over a 360-minute period. RESULTS E(max) and pre-load recruitable stroke work in group II showed significantly better recovery than group I. Blood levels of PMN elastase, creatine kinase MB, lactate and inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6, interleukin-8) were significantly lower in group II. Depletion of myocardial concentration of adenosine triphosphate at 120 minutes after reperfusion and myocardial water content was significantly lower in group II. CONCLUSIONS ONO-5046 Na, which inhibits PMN elastase, could reduce ischemia/reperfusion injury in heart transplantation. These results indicate that clinical application of ONO-5046 Na should be considered.

Penetrating atherosclerotic ulcer.

Abstract The pathogenesis of penetrating atherosclerotic ulcer (PAU) in aortic disease remains controversial. Between January 1995 and April 1999, five patients underwent treatment for a PAU in our hospital. All were men, ranging in age from 46 to 74 years, with a mean age of 66.2 years. The PAU was located on the thoracic descending aorta in three patients and on the abdominal aorta in two. Preoperative diagnosis was established by contrast-enhanced computed tomographic scan and aortogram. Surgery was performed in four patients, as graft replacement in three, and patch plasty in one. The remaining patient is being carefully observed on antihypertensive therapy. No connective tissue disorder, trauma, dissection, or infection was seen in any of the patients who underwent surgery, all of whom had uneventful postoperative courses with no perioperative complications or enlargement of the aorta. We conclude that surgical treatment should be performed for patients with PAU to prevent an aortic catastrophe caused by rapid development of the lesion. This report might provide further evidence of the importance of PAU.

Surgical Treatment of Malignant Fibrous Histiocytoma in the Left Atrium and Pulmonary Veins: Report of a Case

Abstract This report describes the case of a 16-year-old boy who underwent surgical treatment of a cardiac malignant fibrous histiocytoma (MFH). He was admitted to our hospital for exertional dyspnea. An ultracardiogram (UCG) revealed a tumor about 10 cm in diameter, in the left atrium. Extirpation of the left atrial tumor, including the part extending into the pulmonary veins, was performed under cardiopulmonary bypass. Histological examination confirmed a diagnosis of MFH. No adjuvant chemotherapy or radiotherapy was given. While there has been no evidence of local recurrence or metastasis in the 9 months since his operation, strict follow-up is being done by UCG and computed tomography. A few reviews of this entity have been reported; however, they have confused autopsy cases with surgical cases. Therefore, we reviewed only the surgical cases of this type of cardiac tumor documented in the literature. According to our review of the literature, this patient is the youngest among the 42 cases of surgically treated cardiac MFH reported to date.

Thoracic and thoracoabdominal aneurysm repair under deep hypothermia using subclavian arterial perfusion

BACKGROUND Hypothermic circulatory arrest is a valuable adjunct for thoracic and thoracoabdominal aortic aneurysm repair. Retrograde aortic perfusion through the femoral artery, however, carries a risk of cerebral embolism or malperfusion. To avoid these complications we adopted antegrade aortic perfusion through a prosthetic graft attached to the left subclavian artery through a left thoracotomy. METHODS Ten patients had repair of descending thoracic and thoracoabdominal aortic aneurysm under deep hypothermia with antegrade aortic perfusion through the left subclavian artery. Hypothermic circulatory arrest was used because proximal aortic control was hazardous due to rupture or intraluminal disease, or for spinal cord protection. RESULTS There was no brain injury and one hospital death. The cause of death was massive bleeding from the gastrointestinal tract not related to deep hypothermia or the perfusion method. All 9 survivors were alive and well after a mean follow-up period of 9 months. CONCLUSIONS Using the left subclavian artery as a site of aortic perfusion can avoid retrograde aortic perfusion, hence reducing the potential for brain injury due to embolic stroke or malperfusion through a dissected thoracoabdominal aorta.

Surgical repair of a solitary deep femoral arterial aneurysm: report of two cases.

We report herein two cases of a solitary deep femoral arterial aneurysm that were successfully treated by aneurysmectomy and ligation of the deep femoral artery. The patients were a 69-year-old man and a 73-year-old man, both of whom presented with localized pain and a pulsatile mass in the femoral area showing rapid enlargement. Ultrasonography and arteriography confirmed the diagnosis and revealed no evidence of aneurysm or occlusive disease in the other arteries. Aneurysmectomy and ligation of the deep femoral artery were performed, and no ischemic symptoms or thrombus developed postoperatively in either patient. Preoperative arteriography is essential to delineate not only the state of the aneurysm, but also that of the distal arterial tree. An emergency operation is also mandatory due to the rapid enlargement of this type of aneurysm, even if rupture occurs.

Myxoma of mitral valve associated with infective endocarditis

A 20-year-old man was hospitalized for persistent fever, embolism, and syncopal attack. Echocardiography demonstrated a tumor on the mitral posterior leaflet. It was removed under extracorporeal circulation following extirpation of thrombus in the right common like artery. The tumor consisted of myxoma and vegetation with bacterial colony. Myxoma and/or vegetation had destroyed the mitral posterior leaflet. Accordingly, it was necessary to perform mitral valve replacement. The postoperative course was uneventful. This is the 14th surgical case of mitral valve myxoma, and the first case of that associated with infective endocarditis.

Pasteurella multocida Endocarditis: Report of a Case

The present case involves a 48-year-old male patient who presented with Pasteurella multocida endocarditis associated with preexisting mitral valve stenosis. A mitral valve replacement was successfully performed after 3 weeks of intravenous infusion with antibiotics. Pasteurella multocida is a normal inhabitant of the oral cavity of dogs and cats. Therefore, people who have frequent contact with these animals should be examined periodically for signs of infection.

Organ malperfusion in acute aortic dissection.

OBJECTIVE Organ malperfusion in aortic dissection can precipitate a serious condition. The strategy of treatment for it has been controversial. We have focused on the strategy and outcome of acute aortic dissection with organ malperfusion. SUBJECTS AND METHODS Between January 1995 and December 1998, 134 acute aortic dissection patients were admitted. There were 73 males (65.4 +/- 8.0 years old) and 61 females (66.7 +/- 7.4 years old). There were 83 patients of Stanford type A, and 51 patients of type B. Of them, 24 patients (17.9%) were complicated by organ malperfusion. The brain was affected in 4, the heart in 5, the spinal cord in 2, the liver in 1, the intestine in 1, the kidney in 4, and the lower extremities in 10 patients. Our management strategy for a patient with malperfusion in acute aortic dissection was that the antecedent operation was initially mandatory, and central grafting was secondarily considered. RESULTS Refusal of operation or lethal conditions excluded 8 of the 24 patients from operation. An antecedent operation was mandatory in eight of the remaining 16 patients. The overall mortality was 33.3% (8/24 patients), and operative mortality was 31.3% (5/16 patients) in the patients with malperfusion. The overall mortality was 11.8% (13/110 patients), and the operative mortality was 11.1% (9/81 patients) in the patients without malperfusion. CONCLUSION Organ malperfusion is a major component in the management and treatment of acute aortic dissection. Only an appropriate strategy and therapy could result in a satisfactory outcome.

INFECTED ATHEROSCLEROTIC ULCER OF THE ABDOMINAL AORTA AS A CAUSE OF MYCOTIC ANEURYSM TREATED BY IN-SITU PROSTHETIC GRAFT RECONSTRUCTION : REPORT OF A CASE

A 68-year-old man with an infrarenal mycotic aneurysm underwent successful in-situ graft reconstruction using a woven Dacron graft. A tissue culture taken from the excised aortic wall revealedStaphylococcus epidermidis, and histological study subsequently showed penetrating atherosclerotic ulcers (PAU) involving all layers of the aortic wall and marked neutrophilic infiltration with abscess formation inside the ulcer. Atherosclerotic aortic lesions such as PAU are considered susceptible to bacterial infection, which may lead to the formation of an aneurysm after destruction of the vessel wall. Hence, elderly hypertensive patients, being at high risk for such aortic pathology, require careful studies performed to assess the aorta. The usefulness of computed tomographic (CT) scans to determine the presence of PAU or surrounding inflammation should be borne in mind even when a small mycotic aneurysm exists.