Yoshihide Sawada

Increased local angiotensin II formation in aneurysmal aorta.

We investigated the levels and locations of angiotensin II-forming enzymes, angiotensin converting enzyme (ACE) and chymase, in aneurysmal and normal aortas. Aneurysmal aortic specimens (n = 14) were obtained at the time of operative aneurysm repair from 14 patients ranging in age from 57 to 84 y. Normal aortic specimens (n = 16) were obtained from 16 patients (48 to 72 y) who underwent coronary artery bypass surgery. The ACE and chymase activities were determined using each specimen. Sections of each specimen were immunostained with antibodies for ACE and chymase. The ACE activities in the aneurysmal and normal aortas were 0.82 +/- 0.10 and 0.14 +/- 0.05 mU/mg protein, respectively, and this difference was significant. The chymase activities in the aneurysmal and normal aortas were 17.9 +/- 2.40 and 1.02 +/- 0.18 mU/mg protein, respectively, and this difference was also significant. In the aneurysmal aorta, ACE-positive cells were detected with macrophages in the intima and media and chymase-positive cells were detected with mast cells in the media and adventitia, whereas positive ACE and chymase cells in the normal aorta were located only in the endothelium and adventitia, respectively. Angiotensin II-forming enzymes, chymase and ACE, were significantly increased in the aneurysmal aorta, and increased angiotensin II may be associated with the development of aneurysmal formations.

Combined coronary revascularization and splenectomy

Idiopathic thrombocytopenic purpura is rarely associated with coronary artery disease. In this report, we describe the successful surgical management of a patient with idiopathic thrombocytopenic purpura and angina pectoris.

Angiotensin II receptor antagonist, L-158,809, prevents intimal hyperplasia in dog grafted veins.

We investigated the levels of the angiotensin II-forming enzymes, chymase and angiotensin converting enzyme (ACE), in dog grafted veins, and studied the effect of an angiotensin II type 1 receptor antagonist, L-158,809, on vascular proliferation in the grafted veins. The right external jugular vein was grafted to the ipsilaterial carotid artery. In the group treated with L-158,809, the drug (10 mg/kg per day, p.o.) were administered orally from 7 days before the operation to 28 days after it, while the others were administrated placebo. In the placebo-treated group, the chymase activity in the grafted veins was increased about 10-fold and the ACE activity was doubled. The areas of intima and media were significantly increased in the grafted veins in the placebo-treated group. L-158,809 significantly reduced the intimal area of the grafted veins. An angiotensin II receptor antagonist, L-158,809, prevented the vascular proliferation in the grafted veins, and the development of the proliferation may depend on activation of local angiotensin II formation.

Descending branch of lateral femoral circumflex artery as a free graft for myocardial revascularization : A case report

The lateral femoral circumflex artery (LFCA) is one of the branches of the deep femoral artery. In the field of plastic and reconstructive surgery, the LFCA has been used to supply composite tissue of skin and/or muscle. 1-3 The LFCA has three major branches: the ascending, transverse, and descending branches. The descending branch of the LFCA passes downward through the intermuscular space between the rectus femoris muscle and the vastus lateralis muscle and finally terminates in the vastus muscle near the knee joint, The descending branches of the LFCA have a very large diameter (2 to 3 ram) and do not taper like those of the radial arteries. 3 The descending branch of the LFCA has an attractive caliber and length. We report the first case in which a descending branch of the LFCA was used as a graft for myocardial revascularization. A 77-year-old woman had a 7-month history of increasing angina on exertion. ElectrocardiOgraphic changes were consistent with effort angina. Cardiac catheterization revealed a 99% stenosis of the proximal right coronary artery and a 75% stenosis of the middle third of the left anterior descending coronary artery. For this patient, we had planned to perform coronary artery bypass grafting (CABG): a left internal thoracic artery (LITA) in situ to the left anterior descending coronary artery and a saphenous vein graft to the right coronary artery. However, the saphenous vein had varices and was unacceptably thin. We also decided to avoid grafting the right internal thoracic artery to the right coronary artery for this elderly woman because devascularization of the sternum suggested a greater risk of sternal wound infections with the use of bilateral internal thoracic artery grafts. We concluded that the descending branch of the LFCA could be used to bypass the right coronary artery. We had evaluated the descending branches of the LFCA bilaterally by means of a femoral arteriogram 5 days before this operation. The arteriogram showed a good qUality vessel Without stenosis (Fig. 1). The descending branch of the left LFCA was harvested

Comparison of prostacyclin production of human gastroepiploic artery and saphenous vein

The prostacyclin production of the gastroepiploic artery (GEA) and saphenous vein (SV) were studied in 5 patients undergoing coronary artery revascularization. The GEA produced 90.0 +/- 11.9, 132.4 +/- 13.7, and 191.1 +/- 21.8 pg/mg tissue (mean +/- standard error of the mean) of 6-keto-prostaglandin F1 alpha (prostacyclin metabolite) after 2.5, 5.0, and 10.0 minutes, respectively, of incubation in Krebs-Henseleit buffer at 37 degrees C. The SV produced 39.8 +/- 7.0, 66.7 +/- 9.1, and 123.6 +/- 15.1 pg/mg tissue of 6-keto prostaglandin F1 alpha after 2.5, 5.0, and 10.0 minutes, respectively, of incubation. The GEA produced significantly more 6-keto-prostaglandin F1 alpha than SV at all three sampling times up to ten minutes of incubation (p less than 0.01). Prostacyclin is a potent vasodilator and an inhibitor of platelet aggregation. Prostacyclin production by the internal mammary artery was reported to be much higher than that of SV, and the patency rate of internal mammary artery grafts is reported to be better than that of SV grafts in coronary artery revascularization. Therefore, our results suggest that the patency rate of GEA grafts may be better than that of SV grafts in coronary artery revascularization. The GEA is a promising and excellent graft from the biochemical point of view.

Right ventricular myxoma: report of a case.

We herein report a 36-year-old man who underwent surgical resection for myxoma. Preoperative two-dimensional echocardiography demonstrated a mass in the right ventricle. Intraoperatively, the tumor was found to derive from an anterior papillary muscle of the tricuspid valve. The tumor was successfully excised and the tricuspid valve was repaired with chordoplasty and annuloplasty. A histopathological examination revealed myxoma and a 2-year follow-up has shown no evidence of recurrence or tricuspid valve regurgitation.

Right ventricular myocardial infarction and late cardiac tamponade due to right coronary artery aneurysm —A case report—

Coronary artery aneurysm is a relatively rare disease, which may cuase angina, myocardial infarction, or sudeen unexpected death due to thrombosis, emboliozation or rupture. This report describes a case of a 46 year old male who suffered an inferior myocardial infarction with right ventricular involvement, third degree atrioventricular block, cardiogenic shock and late cardiac tamponade, all caused by a right coronary artery aneurysm. He was successfully treated with emergency coronary artery bypass grafting. A review of the literature is also given to emphasize the importance of prompt recognition and correct management of the coronary artery aneurysm.

Coronary artery bypass graft surgery in dialysis patient

To determine the operative outcome of coronary artery bypass graft surgery (CABG) for severe coronary artery disease in long-term hemodialysis patients, we analyzed a group of 16 patients who underwent CABG over a ten-year period in our institution. Hospital mortality was 12.5% (2 of 16 patients). These two patients died of ischemic colitis and perioperative myocardial infarction, respectively. There were five late deaths: one patient died from myocardial infarction, one from uremia, one from gastro-intestinal bleeding, one from gastric cancer and one from unknown cause. There were four significant postoperative complications (morbidity 25%), consisted of one pulmonary tuberculosis, one sternal dehiscence secondary to mediastinitis, one mediastinal hematoma secondary to late bleeding from the LITA dissection area and one A-V shunt trouble. Graft patency rate within the first two months was 93% (30 to 42 in 13 patients). Hospital survivors experienced complete relief from angina. Actuarial survival was 68.8% at 3 years, 57.3% at 5 years and 28.6% at 7 years. This rate is not significantly different from the survival of all dialysis patients, but seems to be better than that of dialysis patients with not operated coronary artery disease. We concluded that CABG in dialysis patients can be accomplished with acceptable morbidity and mortality and effective relief of symptoms.

INDICATIONS AND PROBLEMS OF CORONARY ARTERY BYPASS GRAFTING WITHOUT CARDIOPULMONARY BYPASS

As an alternative method of myocardial protection and to obviate the inherent risks of cardiopulmonary bypass (CPB), we have been performing coronary artery bypass grafting (CABG) without CPB in carefully selected patients. Since the first such operation was successfully performed in Junuary 1995 on a patient with angina pectoris and lung cancer, four other patients have subsequently undergone this technique. This series of 5 patients, being 1 man and 4 women ranging in age from 68 to 80 years, is presented in this report. The reasons for the selection of this procedure were concomitant diseases including lung cancer, a calcified aorta, and myocardial infarction. The mean time of ischemia for each anastomosis was 15.3 ± 5.3min, and the maximum cardiac muscle creatine phosphokinase (CPK-MB) was less than 14 unit/l postoperatively. None of the patients required ventilatory support for longer than 24h postoperatively, and oral intake was started within 24h after extubation in all patients. Postoperative angiography confirmed graft patency and none of the patients developed any ischemic symptoms. All the patients were discharged between 1 and 2 months postoperatively. Thus, the off-pump technique is useful when concomitant diseases are present and will become an alternative method of treatment for coronary artery disease in selected patients.

Free arterial graft as internal mammary artery-Y complex

Because of excellent surgical results obtained with in situ internal mammary artery grafts, recent efforts have been made to extend the use of arterial conduits. In this study 2 cases of coronary revascularization using free internal mammary artery and gastroepiploic artery grafts as an internal mammary artery-Y complex are described. We believe that complete revascularization with only arterial conduit can be achieved more widely by using this technique.