[Surgical treatment of acute aortic dissections--a clinical study using a ringed intraluminal graft].

From 1984 to 1994, surgery was performed using a ringed intraluminal graft (RIG) in 75 patients with acute aortic dissection (DeBakey's type I in 37 cases, type II in 10 cases and type III in 28 cases). The operative death rate was 24% for type I, 30% for type II and 21% for type III. The average time from onset to surgery was short (47 +/- 67 hours for type I, 34 +/- 36 hours for type II and 47 +/- 77 hours for type III). The outcome of these cases indicated that this technique was effective for saving the lives of patients in the acute early stage of aortic dissection. No characteristic complications developed after this surgery. The postoperative course of patients was followed by using CT scans, MRI, angiography. No patients developed aneurysmal formation in the ligated area or dislocation of the RIG. There were no deaths directly attributable to the RIG. Patients who were autopsied in the late postoperative period showed no aneurysm of the ligated area or necrosis of the aortic wall. In conclusion, RIG surgery effectively saved the life of patients with acute aortic dissection and the RIG could be used as prosthetic graft for long-term periods.

Nephrotic syndrome associated with subacute bacterial endocarditis (SBE): a case report.

We experienced a female nephrotic patient associated with subacute bacterial endocarditis. Her proteinuria was completely normalized after antibiotic therapy and valve replacement. Immunofluorescence and an electron microscopic study of a renal biopsy specimen showed little evidence of immune complex in the glomeruli. Marked deposition of properdin in the glomeruli and the reduced level of serum complement may indicate involvement of the complement system in the pathogenic mechanism of massive proteinuria in this case.

Surgical treatment of infective endocarditis.

From February, 1975 through October, 1990, 26 patients underwent surgical treatment for infective endocarditis at Tokai University Hospital. The overall operative mortality rate was 11.5% (3/26). The three patients who died were suffering from aortic prosthetic valve endocarditis (PVE) in the active stage. Among 16 patients in the active stage, the mortality rate was 18.7% (3/16) Among 10 patients with native valve endocarditis (NVE) in the healed stage, all survived. Among the total of 21 patients with NVE, the mortality rate was zero and among those with PVE, the rate was 60% (3/5). Various species of streptococci were the most common organisms encountered, followed by Staphylococcus epidermides. The two PVE patients with S. epidermides died. Nine of the 11 NVE cases in the active stage were of the localized type. Only one case of the localized type of PVE suffered from an infected mitral bioprosthetic valve. The 6 extensive-type cases had aortic valve endocarditis (2NVE, 4PVE). Three patients with the extensive type of PVE died. We conclude that patients with infective endocarditis who develop progressive congestive heart failure, recurrent embolization, or progressive sepsis despite antimicrobial treatments, should undergo prompt valve replacement within 7 days after institution of therapy.

Artificial valve replacement for congenital bicuspid aortic valves.

The congenital bicuspid aortic valve functions almost normally provided degeneration does not occur, but complications of infective endocarditis and calcification of the cusps with aging are indications for surgical intervention. We compared 22 cases with an incompetent bicuspid aortic valve (14 cases with stenosis and eight with regurgitation) with 96 cases of acquired tricuspid aortic valve (30 cases with stenosis and 66 with regurgitation) who were treated by aortic valve replacement (AVR) during the same period. Compared with the stenotic tricuspid aortic valve cases, the stenotic bicuspid aortic valve cases: 1) were older at AVR (59.3: 51.7 years, P < 0.05), 2) had a smaller diameter of preoperative valve orifice (6.9: 9.2 mm, P < 0.05), 3) had a smaller valve ring diameter (23.0: 24.3 mm, P < 0.05), 4) used artificial valves of almost identical size (22.0: 22.5), and 5) included no operative deaths (0: 10%). In contrast, compared with the tricuspid aortic valve cases with regurgitation, the bicuspid aortic valve cases with regurgitation: 1) were younger at AVR (39.5: 45.8 years), 2) had a higher incidence of infective endocarditis (62.5: 19.6%, P < 0.02) as a complication, and 3) showed a higher operative death rate (25.0: 6.1%), although this difference was not statistically significant. Suture repair of the incised portion of the aorta must be performed meticulously in patients with prominent poststenotic dilatation of the ascending aorta.

Surgical treatment of non-penetrating injury to the aorta.

During a 17-year period, eight cases of blunt traumatic injury to the aorta were surgically treated at our hospital. The locations of the lesions were the descending thoracic aorta in four cases, abdominal aorta in two cases, and traumatic DeBakey type IIIb dissection in two cases. Surgical repairs were carried out during the acute or subacute period in four cases and others were electively treated during the chronic period. One patient suffering from acute traumatic dissection of the aorta died of acute renal failure following acute ischemia in the lower extremities 10 days after surgery. Accordingly, the overall mortality rate was 12.5% in this series. We believe that elective operations should be carefully considered if they are possible.

[An experimental study on the relation between lung volume and pulmonary blood flow].

The purpose of this study was to elucidate whether or not the reduction of lung volume is related to the mechanism of blood flow reduction in the atelectatic lung. In adult mongrel dogs, whose main stem bronchus in the thoracotomized lung was obstructed, the change of blood flow in the lung containing N2 was compared with that in the collapsed lung. 1) Under a low partial pressure of O2 in the broncho-alveolar system by obstruction of the main stem bronchus, the blood flow did not change, even when the N2 volume in the lung was varied. Therefore, the change of blood flow in the collapsed lung is not attributable to the reduction of lung volume. 2) The lung blood flow increased when the partial pressure of O2 in the broncho-alveolar system was elevated by infusion of O2 into the collapsed lung, and it decreased with the subsequent O2 absorption leading to lung collapse. Therefore, the change of lung blood flow is due to the change of intraalveolar partial pressure of O2. 3) The reduction of blood flow in the atelectatic lung is caused by hypoxic pulmonary vasoconstriction, and is not influenced by the reduction of lung volume due to the lung collapse.

[Combined medical and surgical treatment of 74 cases of acute type III aortic dissection].

In the early period up to 1986, our treatment of acute type III dissection was anti-hypertension drug therapy as a rule, and Collins operations were performed in two cases of progressive hemothorax. Among 21 patients receiving medical therapy, five died of rupture, and three operated cases died of multiple organ ischemia, and then the hospital mortality was 40%. Since 1987, we have selected hypotensive treatment of strictly maintaining blood pressure less than 120mmHg for the completely thrombosed type of the dissected lumen, and the emergency operation of ringed intraluminal graft insertion (RIG operation) for the blood-flow type and aneurysm formation type of the dissected lumen, diagnosed by the emergency cine-angiography. As the result, among 51 cases having hypotensive therapy, one died of respiratory failure. In the 23 operated cases, in which RIG operation and/or arterial reconstruction was performed, four died of multiple organ ischemia. The hospital mortality was 8%, which was significantly improved compared with that of the early period.

[Torsion after left lower lobectomy and cerebral infarction following the re-exploratory thoracotomy: a case report].

A 38-year-old man had a left lower lobectomy for pulmonary carcinoid. Following the operation, torsion of the left residual upper lobe occurred. Re-explosive thoracotomy was performed on the second postoperative day. The left upper lobe showed a clockwise 180-degree rotation. Pneumonectomy was not done. After the re-thoracotomy, the patient developed right hemiplegia. Head CT showed a cerebral infarction due to the thrombus of pulmonary vein that was released after the repair of the torsion.

[Fontan-type operation in a 14-month-old patient with tricuspid atresia who had [I, D, D], pulmonary atresia and right pulmonary artery stenosis].

A 14-month-old male with tricuspid atresia who had [I, D, D], pulmonary atresia, right pulmonary stenosis and a Blalock-Taussig shunt successfully underwent a Fontan-type operation accomplished by making a direct right atrial-pulmonary arterial connection with a Gore-Tex roof patch. The patient had an uneventful postoperative course without development of the heart failure.

[Pathological findings of the aortic wall at the site of ligation against the rigid rings of an intraluminal graft for acute DeBakey type I aortic dissection].

A ringed intraluminal graft has been utilized in the surgical treatment for dissecting aneurysm since 1978. Histological findings of the aortic wall long after surgery, however, have not been described in detail, and concern remains about possible pressure necrosis at the point of encirclement. The following report is for a case of acute type I aortic dissection which required the use of an intraluminal surgical graft in a patient who died eight months postoperatively of a disease unrelated to previous surgical management. The pathological findings at autopsy were as follows. At the site of circumferential ligations around the aorta, 1) discontinuity of the elastic fibers in the media was found only at the outer surface, 2) there was no compression necrosis in the outer half of the media, although a dark shade of elastic fibers was recognized, 3) there were no pathological changes in the inner half of the media. In addition, complete repair of the intimal tear as well as closure of the false lumen replaced by collagen fibers was confirmed histologically in the whole length of aorta where the intraluminal graft had been placed. We conclude that concerns about the fragility of the aortic wall at the site of circumferential ligation, the migration of prosthesis, and the formation of thrombi is alleviated by these pathological observation.

[A case of a 10-year survivor with squamous cell carcinoma of the lung, treated with radiation after an exploratory thoracotomy].

We have experienced a rare case of an unresectable lung cancer in a male patient who has survived 10 years after radiation therapy. The patient was aged 58 at the time of diagnosis. In May 1978, he was hospitalized because of an abnormal shadow in the upper left lung filed, and the diagnosis of squamous cell carcinoma was made by TBLB. Since subsequent surgery revealed an extensive tumor invasion to the large blood vessels, an exploratory thoracotomy was performed. Following postoperative 60 Gy radiation therapy, tumor regression was observed on examination of chest x-ray films. In July, 1988, 10 years and 3 months after this surgery, a back pain developed due to the recurrence of the tumor, and radiation therapy was given again. This relieved the pain. As of December 1988, he receives treatment on an outpatient basis and his performance status has been excellent.

[Diffuse B-cell lymphoma of anterior mediastinum cured by short-term administration of CDDP-containing regimen].

The following report is of a case of diffuse B-cell lymphoma of the anterior mediastinum that was originally treated by resection and radiation in a patient who had pleural and subcutaneous metastases four months after operation. A total dose of 120 mg of CDDP, 60 mg of BLM, and 15 mg of VBL was administered in five weeks. The metastases completely disappeared by this dose alone, and the patient is alive and well seven and a half years after the chemotherapy.

[Early detection of central nervous system dysfunction during cardiopulmonary bypass using EEG monitoring].

The EEG was monitored in fifty-four patients during and after various surgeries requiring cardiopulmonary bypass (CPB) to assist in the early detection of central nervous system dysfunction (CNSD). Bilateral frontopolar EEG signals were processed with a 2-channel, real-time Fast-Fourier-Transformer (FFT) analyser and Compressed Spectral Arrays (CSA) were obtained. The fifty-four patients were divided into 3 groups based upon clinical outcome; Group 1: patients without CNSD (83%); Group 2: patients with delayed recovery from anesthesia but without CNSD (4%); and Group 3: patients with apparent postoperative CNSD (13%). There was no difference in the CSA among these groups prior to rewarming, but after the rewarming phase, two distinct sets emerged. Groups 1 and 2 showed a shift of the CSA predominant peak from a low frequency to a higher frequency. On the other hand, Group 3 patients demonstrated either stable predominant peaks in the lower frequencies or gradual flattening of the CSA. We conclude that the intra-operative EEG monitoring is a useful tool for the early detection of CNSD during and after CPB.