Atsuro Takeuchi

Coronary Artery Bypass Grafting by Utilizing In Situ Right Gastroepiploic Artery: Basic Study and Clinical Application

The right gastroepiploic artery (GEA) was studied angiographically and histologically to determine its suitability for coronary artery bypass grafting. One hundred celiac angiograms demonstrated that the right GEA has the appropriate size (diameter less than 1.5 mm, 4%; 1.5 to 2 mm, 29%; more than 2 mm, 67%) and length (less than half of the greater curvature, 5%; more than half of the greater curvature, 95%; more than two-thirds of the greater curvature, 34%) for use as an in situ graft. A stenotic lesion of a GEA was observed in only 1 angiogram. Histological examination of a right GEA from 5 patients who had undergone gastrectomy demonstrated no evidence of arteriosclerosis. Encouraged by these results, we performed a coronary artery bypass reoperation utilizing an in situ right GEA graft in 2 women. Postoperative angiograms showed good patency of those grafts. The patients recovered well and were free from angina.

Myocardial revascularization with combined arterial grafts utilizing the internal mammary and the gastroepiploic arteries

Coronary artery bypass grafting with a combined arterial graft using both the internal mammary artery and the right gastroepiploic artery was performed in 22 patients during a 21-month period. There were 17 men and 5 women ranging in age from 34 to 73 years (mean age, 53.4 years). Three patients were having a reoperation, and 2 patients had no segment of long saphenous vein available. Twelve patients were less than 55 years old. The mean number of distal anastomoses including vein grafts was 3.2 and the mean number of arterial grafts was 2.5 per patient. The mean aortic cross-clamp time was 63.8 minutes and the mean cardiopulmonary bypass time was 116.7 minutes. There was 1 early and 1 late death. The other 20 patients are alive without angina. Studied within 3 postoperative months, graft patency was 95% (19/20) in internal mammary artery and 93% (14/15) in gastroepiploic artery grafts. It is concluded that the combined arterial graft can be used safely and effectively, and its application facilitates complete revascularization with more arterial and fewer vein grafts.

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.

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.

Application of Ultrasonic Aspirator for Dissection of the Internal Mammary Artery in Coronary Artery Bypass Grafting

The low-power ultrasonic aspirator was used for the dissection of the internal mammary artery (IMA) in 20 patients undergoing coronary artery bypass grafting. Harvesting time was shorter and the amount of bleeding was less than with the ordinary method. The short-term patency rate (1 to 6 months) for those IMA grafts was 95% (19 of 20 remained patent). These results have encouraged us to use the ultrasonic aspirator routinely for IMA dissection.

Combined Revascularization of Coronary and Femoral Arteries: A Proposed Alternative

Two patients with both coronary artery disease and leg ischemia were successfully treated with a combined revascularization procedure. Coronary arteries were bypassed with in situ internal mammary artery grafts, and bilateral femoral arteries were bypassed with expanded polytetrafluoroethylene grafts descended from the ascending aorta through the preperitoneal abdominal wall tunnel. Both patients recovered well and experienced no angina or claudication.

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.

Vein Holder for Coronary Bypass Surgery

Two types of vein holder were designed to facilitate coronary bypass surgery. One is designed for vein graft-to-coronary artery anastomosis and is particularly useful for the side-to-side anastomosis in sequential grafting. The other is designed for vein graft-to-aorta anastomosis and enables anastomosis by one surgeon. The vein holder holds the vein graft in a three-dimensional position without the need of forceps, which protects the vein graft wall from crush injuries caused by vascular forceps.

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.

Augmentation of coronary bypass graft flow induced by dipyridamole and its relation to bypass graft patency

To evaluate the effect of dipyridamole on coronary bypass graft flow, 10 mg of dipyridamole was injected intravenously, during the measurement of graft flow, at the time of surgery. Its concentration in serum was measured and compared with that after oral administration. In 50 individual vein grafts performed on 35 patients, graft flow increased from 65 ±37 to 96±55 ml/min (p<0.001) after the dipyridamole injection and the arterial pressure decreased slightly. In 40 grafts whose graft flow was increased by more than 10 ml/min by dipyridamole, the patency rate (at 5 weeks) was 98 per cent, whereas that of the 10 other grafts, which responded poorly, was only 50 per cent (p<0.01). The serum concentration of dipyridamole, 3 minutes after intravenous injection, was 1.46±0.68 μg/ml, while the level of orally administrated dipyridamole, in 3 groups of patients who were given 50 mg, 75 mg and 100 mg, three times a day, respectively, was steady, being 0.68±0.20 μg/ml, 1.43±0.41 μg/ml and 1.73±0.50 μg/ml, 2 hours following ingestion. We concluded that intravenous dipyridamole increases the graft flow and that a better patency is obtained in those grafts in which the graft flow is increased by more than 10 ml/min. It is also expected that routine doses of oral dipyridamole possibly increase the graft flow after coronary bypass surgery.