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Endovascular stent grafting for aortic aneurysms/dissections using metallic stents covered with conventional vascular grafts has attracted attention as a minimally invasive alternative to open surgery. Since the first clinical experience of endovascular stent grafting for abdominal aortic aneurysm was reported in 1991, numerous clinical applications have been undertaken worldwide. Although several commercial bifurcated stent grafts for abdominal aortic aneurysm are available in various countries, including Europe, the USA, and Australia at present, none of the devices are approved for clinical use in Japan. Particularly for thoracic aortic aneurysms, hand-made devices are still used in individual institutions. Endovascular stent grafting is feasible for aneurysm repair within limited conditions. Although further investigation is necessary to clarify the indications, it is clear that aortic aneurysms could be successfully treated with precise stent-graft deployment and proper patient selection based on our 10-year follow-up results.

Endovascular stent grafting for aortic aneurysms using metallic stents covered with conventional vascular grafts has attracted attention as a catheter-based, minimally invasive alternative to open surgery. Since the first clinical experience with endovascular stent grafting for an abdominal aortic aneurysm was reported in 1991, experimental and clinical investigations have between undertaken world wide. Although several commercial bifurcated stent grafts for abdominal aortic aneurysms are currently available in Europe and Australia, none of the devices are approved for clinical use in Japan and the USA. Hand-made devices are still used in each institution particularly for thoracic aortic aneurysms. Endovascular stent grafting is feasible for aneurysm repair within limited conditions. However, several unsolved issues remain concerning not only delivery devices which require precise skill in stent-graft deployment, but also concerning patient selection and proper indications. Further investigation is necessary to clarify graft durability, aneurysmal neck enlargement, and the fate of the excluded aneurysm sac for long follow-up periods.

Activated platelet function indicated by beta-TG and PF4 is observed in the patients from arteriosclerosis obliterans (ASO) with severe disturbance of peripheral circulation. Increase in FpA, TAT, FDP and PIC suggest that blood coagulation and fibrinolysis are accelerated. Fibrinolysis might be activated in response to thrombus formation in screlotic peripheral artery. It is suggested that antiplatelet and/or anticoagulation therapy is acceptable for ASO with disorders of blood coagulation and fibrinolysis. Adequate antithrombotic therapy is necessary not only to treat ASO but also to prevent progression of arterioscrelosis. It is important to recognize harmful influence of antithrombotic therapy (antiplatelet, anticoagulation or thrombolysis) on blood coagulation and fibrinolysis, on the patient being canditate for vascular surgery.

In order to clarify the propriety of surgical treatment for intermittent claudication caused by arteriosclerosis obliterans (ASO), indication for vascular reconstruction and efficacy of surgery on patient's quality of life were investigated. Bypass surgery or laser angioplasty (PTLA) was undertaken in 149 of 188 ASO patients. Because of high risk factors (renal failure, ischemic heart disease, cerebro-vascular disturbance or malignant tumor), 39 patients were treated conservatively. Intellectual dysfunction in aged patient was evaluated by Okabe's brief mental scale test. Coronary artery disease was revealed by coronary angiography performed next to routine dipyridamole-loaded ECG in 19 to 78 patients. CABG or PTCA was performed prior to peripheral vascular reconstruction in 3 patients with serious coronary disease. Extra-anatomical bypass or PTLA was indicated mainly in patients with coronary artery disease or intellectual dysfunction. The anatomical bypass and the extra-anatomical bypass were undertaken in 88 and 61 patients respectively. Graft occlusion was observed in 8 cases. Patency rate of the anatomical bypass was 96.6% and that of the extra-anatomical bypass was 91.8%, at 32 months of postoperative mean follow-up period. The operative mortality rate was 2.7%. There was no major amputation due to graft occlusion.

Contact laser thermal angioplasty with a metal hot tip heated by an Argon laser system (Trimedyne Inc.) was performed on 34 peripheral arterial occlusive or stenotic regions (7 iliac, 20 femoral and 7 popliteal arteries) in 22 patients with ASO. The early clinical results of laser angioplasty were investigated by comparing those of 15 patients treated by percutaneous transluminal balloon angioplasty (PTA). There was no perforation of the arterial wall caused by thermal ablation with the hot tip heated by repeated pulses under power conditions of 10 watts of laser energy for 5 seconds. Detachment of the hot tip caused by frequent healing without a sufficient period of tip cooling was observed in 2 cases. Acute thrombosis was observed in 1 patient during reconstruction of the proximal artery. The initial success rate of laser angioplasty and PTA was 91.2% and 86.7%, respectively. Re-stenosis or occlusion was observed in 7 of 31 regions 6 months after laser angioplasty. Satisfactory results were not obtained in the femoral artery. The overall patency rate of laser angioplasty and PTA was 77.4% and 69.2%, respectively. The initial success rate of laser angioplasty in totally obstructed arterial regions was higher than that of PTA.

The usefulness and limitation of intraoperative angioscopy in the field of cardiovascular surgery were investigated based on our clinical experience. Considerable leakage of cardioplegic solution through the aortic valve due to valve regurgitation was angioscopically demonstrated when the infusion pressure in the aortic root was less than 10 mmHg. This indicates that the cardioplegia must be infused with an aortic pressure of above 20 mmHg for appropriate myocardial protection. After thromboendarterectomy on the arteriosclerosis obliterans, fixation with the edge of the residual intimal flap to the arterial wall was performed correctly under direct visualization. The status of thrombus organization in deep vein thrombosis was evaluated. Even after complete thrombectomy, iliac compression was still demonstrated. Blood in the cardiovascular lumen can be easily cleaned by saline flushing. However, careful attention to fluid overloading must be employed when the observation period is prolonged.