Ichiya Yamazaki

Measurement of cytokine levels by coronary sinus blood sampling during cardiac surgery with cardiopulmonary bypass

Interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase levels in coronary sinus blood were measured and compared with those in arterial blood drawn from the radial artery before and immediately after cardiopulmonary bypass (CPB) during coronary artery bypass grafting in 20 patients. We introduced coronary sinus blood sampling as a useful method for evaluation of myocardial metabolism, myocardial protection, and reperfusion injury during CPB, especially by measurement of cytokines. Because interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase are inflammatory mediators, we speculated that they might show higher levels in coronary sinus blood than in systemic arterial blood. The results obtained from the 20 patients showed that levels of interleukin-6, interleukin-8, and polymorphonuclear leukocyte elastase increased immediately after CPB (p < .01), but there was no significant difference in these levels between coronary sinus and systemic arterial blood. We conclude that the myocardium is not a predominant source of their release during CPB. Our results also showed that the measurement of these cytokines in systemic arterial blood reflected their levels in the whole body, including the myocardium, even during cardiac operation with CPB.

Flow dynamics in internal thoracic artery grafts 10 years after coronary artery bypass grafting.

BACKGROUND Flow dynamics in internal thoracic artery grafts 10 years after surgery are not known. METHODS Doppler examination was performed in native internal thoracic arteries as a control (n = 8) and in internal thoracic artery grafts to the left anterior descending coronary artery 6 months postoperatively (group A, n = 25), at 5 years (group B, n = 14), and at 10 years (group C, n = 11). RESULTS Each graft group showed a diastolic to systolic peak velocity ratio of less than 1.0 at the proximal end, and more than 1.0 at the distal end, but the control group showed a ratio of less than 1.0 throughout the length of the artery. The diastolic peak velocity of the graft groups was significantly faster than that of the control group at the distal end (versus group A, p < 0.01; versus group B, p < 0.005; and versus group C, p < 0.05). The systolic peak velocity of the graft groups was significantly lower than that of the control at the proximal end (versus group A, p < 0.0001; versus group B, p < 0.005; and versus group C, p < 0.0005). There were no significant differences of flow velocities among the graft groups and graft diameter among the four groups. CONCLUSIONS Although the internal thoracic artery is systolic predominant, when native artery is used as graft, it changes its hemodynamics to diastolic predominance, especially at the distal end. Even after 10 years, graft flow dynamics are unchanged. This hemodynamic character may be one of the factors related to the superior long-term patency.

Angiogenic growth factor release system for in vivo tissue engineering: a trial of bone marrow transplantation into ischemic myocardium

For successful in vivo tissue engineering, a growth factor release system will be useful. We adopted autologous bone marrow transplantation as an angiogenic growth factor release system. Bone marrow transplanted into a synthetic vascular prosthesis produced continuous synthesis of angiogenic growth factors, resulting in rapid neointima formation on the prosthesis after implantation. We expected a similar angiogenic phenomenon to occur if bone marrow was transplanted into ischemic myocardium. Bone marrow was transplanted into ischemic myocardium created in dogs. Marrow cells continued synthesis of angiogenic growth factors, which were effective in protecting the capillary network from ischemia, but not myocytes. Autologous bone marrow was injected intramuscularly into ischemic myocardium created in the left ventricular wall of dogs. Control operations were performed without bone marrow. On days 3 and 7, marrow cells survived, and their adjacent cells and the surrounding extracellular matrix were immunohistochemically bFGF reactive. At 3 weeks, no marrow cells were identified. Myocytes disappeared, but the capillary blood vessel networks remained. With some exceptions, these capillaries did not contain blood cell components. In the controls, scar tissue with a very small number of capillaries was formed. In conclusion, marrow cells survived for a short period of time after transplantation, and continued synthesis of angiogenic growth factors, which were effective in protecting endothelial cells from ischemia, but not myocytes. Therefore, the results also suggest that there are limitations in the treatment of ischemic myocardium using angiogenic growth factors alone.For successful in vivo tissue engineering, a growth factor release system will be useful. We adopted autologous bone marrow transplantation as an angiogenic growth factor release system. Bone marrow transplanted into a synthetic vascular prosthesis produced continuous synthesis of angiogenic growth factors, resulting in rapid neointima formation on the prosthesis after implantation. We expected a similar angiogenic phenomenon to occur if bone marrow was transplanted into ischemic myocardium. Bone marrow was transplanted into ischemic myocardium created in dogs. Marrow cells continued synthesis of angiogenic growth factors, which were effective in protecting the capillary network from ischemia, but not myocytes. Autologous bone marrow was injected intramuscularly into ischemic myocardium created in the left ventricular wall of dogs. Control operations were performed without bone marrow. On days 3 and 7, marrow cells survived, and their adjacent cells and the surrounding extracellular matrix were immunohistochemically bFGF reactive. At 3 weeks, no marrow cells were identified. Myocytes disappeared, but the capillary blood vessel networks remained. With some exceptions, these capillaries did not contain blood cell components. In the controls, scar tissue with a very small number of capillaries was formed. In conclusion, marrow cells survived for a short period of time after transplantation, and continued synthesis of angiogenic growth factors, which were effective in protecting endothelial cells from ischemia, but not myocytes. Therefore, the results also suggest that there are limitations in the treatment of ischemic myocardium using angiogenic growth factors alone.

Long-term outcomes using vascular grafts sealed with fragmented autologous adipose tissue for aortoiliac occlusive disease

The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease.

Formation of Neointima in Vascular Prosthesis Sealed with Autologous Adipose Tissue Fragments for Femoropopliteal Bypass

If the vascular prosthesis had adequate antithrombogenicity and healing ability of the luminal surface, results of revascularization of peripheral artery would be better than they are today. Therefore, the authors gave antithrombogenicity artificially to the fabric vascular prosthesis, which was sealed with tissue fragments, and expected the graft to heal like native arterial wall, and have natural antithrombogenicity after surgery.

Late vasospasm of the inferior epigastric artery graft

We report a case of vasospasm of a free inferior epigastric artery graft at 5-year angiographic follow-up after coronary artery bypass grafting. Although the cause of spasm was not clear, the graft was viable and had a vasoconstrictor profile similar to a gastroepiploic artery graft at long-term follow-up.

Off-pump ligation of a coronary arteriovenous fistula

Continuous murmurs (Levine grade III/VI) were heard in the fourth intercostal space at the left sternal border in an asymptomatic 47year-old woman. Transthoracic echocardiography revealed an enlarged right atrium (RA) and a turbulent flow signal from the coronary sinus (CS) into the RA (Fig. 1). Multi-detector computed tomography (MDCT) revealed an ectatic and tortuous right coronary artery draining into the CS at the surface of the base of the heart (Fig. 2). Off-pump ligation of the coronary arteriovenous fistula (CAVF) was performed through a median sternotomy. We used pericardial deep stitches (LIMA stich) and the StarfishTM Heart Positioner (Medtronic, Inc., Minneapolis, MN) to allow clearer visualization of the base of the heart, and placed the patient in the Trendelenburg position (Fig. 3). The drainage site was identified by palpating the thrills and using epicardial echocardiography. Upon manual clamping, the thrills disappeared and mixed venous oxygen saturation decreased from 80% to 60%. Therefore, we ligated the entry vessel using double ligation with #1 silk thread. Postoperative MDCT revealed no persistence of the CAVF (Fig. 2). The patient had a favorable postoperative outcome.

Reoperative coronary artery bypass grafting via a left thoracotomy and a small laparotomy without cardiopulmonary bypass: report of a case.

Abstract A 66-year-old woman with aortic stenosis underwent an aortic root replacement with a composite graft and coronary artery reconstruction 2 years before presentation. On coronary angiography performed 2 years after operation, saphenous vein graft (SVG) to right coronary artery and SVG to first diagonal branch had both become totally occluded. SVG to left anterior descending artery showed 75% stenosis on the heel side of the distal anastomosis. The patient underwent a second coronary artery bypass via a left thoracotomy (the left internal thoracic artery was anastomosed to the first diagonal branch by interposing it with the left radial artery) and a small laparotomy (the right gastroepiploic artery was anastomosed to the right coronary artery) without a cardiopulmonary bypass. This approach is preferable to avoiding both a resternotomy and cardiopulmonary bypass in patients requiring repeat surgery.

Clinical Results of Long and Short Saphenous Vein Stripping for Primary Varicose Veins

To review the long term clinical results of long and short saphenous vein stripping (LSS) as radical operation for primary varicose veins.

Treatment of Acute Renal Failure Following Cardiovascular Operation Using Extracorporeal Circulation. Comparison between Continuous Peritoneal Dialysis(CPD) and Continuous Arterio-Venous Hemofiltration(CAVH).

体外循環による手術後1週間以内に急性腎不全 (ARF) に陥った症例のうち, 保存的治療が無効の16例に対し血液浄化療法として連続腹膜灌流 (CPD) および持続的血液濾過 (CAVH) を行った. CPDのみを行った7例をCPD群, CPD施行中にCAVHに移行した5例をCPD→CAVH移行群, 最初からCAVHを行った4例をCAVH群とした. 各群の離脱, 生存率をみると離脱率はCPD群33%, CPD→CAVH移行群20%, CAVH群67%で, 生存率はCPD群33%, CPD→CAVH移行群20%, CAVH群0%と不良であった. 除水量と血清カリウム値のコントロールに関しては両方法とも十分有効であった. クレアチニンクリアランス (Ccr) はCAVHがCPDに勝る傾向にあったが, CAVHのCcrも平均11.3ml/minと低値であり, 血清クレアチニン値, 血清尿素窒素値のコントロールは両方法とも不十分であった. 合併症はCPD施行例では12例中3例に低蛋白血症がみられたのに対してCAVH使用例にはより重篤な合併症である出血症状が9例中7例にみられた.