Tsuguo Hasegawa

Interleukin 6 gene transcripts are expressed in human atherosclerotic lesions

Factors controlling the proliferation of vascular smooth muscle cells (SMC) are thought to be key elements in the progression of atherosclerosis. We have previously shown that interleukin 6 (IL-6) stimulates the growth of SMC in vitro and that IL-6 gene transcripts are expressed in atherosclerotic lesions of genetically hyperlipidemic rabbits. To understand the involvement of IL-6 in the development of human atherosclerosis, we investigated IL-6 mRNA expression in atherosclerotic arteries from patients undergoing surgical vascularization, utilizing reverse transcription polymerase chain reaction (RT-PCR) and in situ hybridization analyses. In RT-PCR analysis, the atherosclerotic arteries showed 10- to 40-fold levels of IL-6 mRNA expression over the non-atherosclerotic artery. In in situ hybridization analysis, IL-6 gene transcripts were observed in the thickened intimal layer of atherosclerotic lesions. These results strongly suggest the involvement of IL-6 in the development of human atherosclerosis.

Infectious Mediastinitis After Cardiac Operations: Computed Tomographic Findings

BACKGROUND Infectious mediastinitis after cardiac operations is of great concern to cardiac surgeons because of its poor prognosis. Prompt surgical interventions such as debridement and irrigation are the key to treatment of infectious mediastinitis. METHODS We surveyed retrospectively the cases of 722 consecutive cardiac surgery patients at our hospital. Mediastinitis developed in 21 patients after the cardiac operation. We performed computed tomography in 11 of these patients before resternotomy and in 10 patients as the control 2 to 3 weeks after the cardiac operation. RESULTS Mediastinal soft tissue swelling was seen in 7 patients, bilateral pleural effusion was found in 9 patients, sternal dehiscence or sternal erosion was observed in 8 patients, and subcutaneous fluid accumulation was found in 7 of the mediastinitis group. Unilateral pleural effusion was seen in 6 and bilateral effusion in 1, and mediastinal soft tissue swelling was seen in 1 patient of the control group. CONCLUSIONS Our study showed that mediastinal soft tissue mass combined with bilateral pleural effusion can be a characteristic computed tomography finding in poststernotomy infectious mediastinitis, and that chest computed tomography is more sensitive to detecting sternal dehiscence, sternal erosion, and subcutaneous fluid accumulation.

Clinical experience with an anatomic snuff box arteriovenous fistula in hemodialysis patients.

&NA; The present study was performed to evaluate the clinical usefulness of an anatomical snuff box arteriovenous fistula with special reference to its short‐term and long‐term patency in 139 hemodialysis patients. A snuff box fistula was established in 139 patients, including 39 with diabetic nephropathy (DN group) and 100 with non diabetic nephropathy (non DN Group). Fistula blood flow was measured by Doppler ultrasound in 18 patients. Early and late obstruction was observed in 24 (17%) of the 139 patients. The long‐term patency rate of the snuff box fistula in the non DN group was 87% at 57 months, whereas the patency rate at 57 months in the DN group (72%) was significantly (p < 0.05) lower than that in the non DN group. The increase in arterialized vein blood flow in DN patients was less marked than that in the non DN patients. These results suggest that the high prevalence of late obstruction in DN patients may partly be reflected by an insufficient increase of arterialized vein blood flow at the snuff box site. ASAIO Journal 1996;42:177‐180.

Pleural adenosine deaminase levels in tuberculous pleurisy —Its diagnostic performance under the different prevalences in the different age of population—

In the diagnosis of pleural effusion, tuberculous pleurisy should always be considered because the prevalence of tuberculosis in Japan remains high. The measurement of adenosine deaminase (ADA) levels in pleural fluid is useful for the diagnosis of the tuberculous pleurisy because of its high sensitivity and specificity. However, no studies have addressed the post-test probability (= positive predictive value; PPV) of the test. Since the PPV depends on the pre-test probability (= prevalence) of the tuberculous pleurisy that varies with age, we have retrospectively evaluated the PPV in the different age population; the young (-35 years of age), the middle (36-65 years), and the old (66-years). A total of 208 data sets were collected; the tuberculosis (n = 52), malignancy (n = 34), non-specific infection (n = 31), transudates (n = 45), the others (n = 36), and unknown causes (n = 10). It was found that 1) the prevalence of tuberculous pleurisy was decreased with age, (70% in the young, 28.7% in the middle, and 8.5% in the old), 2) the PPV was the lowest in the old (53.8%), while the highest in the young (95.0%), and 3) no significant correlation was found between age and the ADA activity in pleural effusion.

Isolated tricuspid valve stenosis caused by infective endocarditis in an adult: Report of a case

We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause.

The Role of Leukocyte Depletion by in Vivo Use of Leukocyte Filter in Lung Preservation After Warm Ischemia

The oxygen metabolites of leukocytes have been implicated as playing the central role in reperfusion injury of preserved lung for transplantation. Furthermore, it is still unknown how leukotrienes take part in this process. Twelve mongrel dogs were used, divided into two groups. In group A, left thoracotomy and hilar stripping of the left lung was performed under anesthesia. During warm ischemia (two hours) and reperfusion (two hours), a filter was used three times between the femoral artery and vein, and quantitative in vivo blood filtration was performed. In group B, warm ischemia and reperfusion was done in the same fashion without filtration. As for tissue free radical assay, lipid peroxidation products were measured by means of thiobarbituric acid. Tissue leukotriene B4 and C4 levels were measured by radio immunoassay. In addition, peripheral blood count and tissue wet/dry ratio were analyzed. Significant leukocyte depletion of peripheral blood with leukocyte efflux from reperfused lung was observed in group A. Significant increase of tissue malondialdehyde (MDA) titers after reperfusion was observed in group B, whereas no significant fluctuation of tissue MDA titers was noted in group A. Concerning leukotriene B4 and C4, no significant increase was observed in either group. Tissue damage estimated by lung wet/dry ratio was considered to be controlled in group A compared with group B. Thus, the authors conclude that in vivo use of a leukocyte filter is efficient in removal of peripheral blood leukocytes and in preservation of reperfused lung after warm ischemia and that oxygen metabolities of leukocytes are considered to play a role in tissue damage in this process.

Three-channeled aortic dissection

A 68-year-old woman in whom a thoracic aortic dissection (DeBakey type III) had been followed up for 6 years was admitted to our hospital with a complaint of chest pain. A graft replacement of the descending thoracic aorta was performed. A communication between the second and third channels was detected intraoperatively. Nine cases of three-channeled aortic dissection whose third dissection existed within the outer wall of the second one were previously reported, and 4 of them had a communication between the two false channels.

Transseptal left-heart catheterization with Swan-Ganz flow-directed catheter

Four cases of transseptal left-heart catheterization with the use of a Swan-Ganz flow-directed balloon-tipped catheter are reported. An 8.5F Teflon catheter covered with a Teflon tube (4 mm outer diameter) was inserted into the left atrium by the Brockenbrough technique. A Swan-Ganz catheter was then introduced into the left atrium through the Teflon tube and left-heart catheterization was performed. Unlike conventional methods, this method made it easier to insert a catheter into the left ventricle and also enabled advancement of the catheter into the aorta. Our experience suggests that this method is a valuable addition to cardiac catheterization laboratories.

The effectiveness of transesophageal ultrasonography in preoperatively diagnosing an esophageal cyst in a 75-year-old woman: Report of a case

We present herein the unusual case of a 75-year-old woman in whom an esophageal cyst was preoperatively identified with the aid of transesophageal ultrasonography. She underwent successful extirpation and has remained well since her discharge from hospital. The transesophageal ultrasonogram was shown to be a powerful diagnostic tool for the identification of a mediastinal mass located adjacent to the esophagus.

Rapidly growing mural thrombus in an abdominal aortic aneurysm

SummaryWhile mural thrombus accompanied by an abdominal aortic aneurysm (AAA) is not rare, the growth rate of such a thrombus has not yet been adequately documented. We present here a very rare case of a 62-year-old female patient with an AAA in whom the mural thrombus in the aneurysm grew very rapidly over a short period. We could follow the growth of the mural thrombus in the AAA by two-dimensional (2-D) abdominal echography. Patients with an AAA must be closely monitored by this technique which is able to detect the presence of the thrombus and allow evaluation of its growth.