To evaluate the role of interleukin-8 (IL-8) and interleukin-10 (IL-10) in reperfusion injury following acute arterial occlusion, an experimental study was carried out using Wistar strain rats. The reperfusion injury model was conducted in 4 rats, in which the infra-renal aorta and the bilateral common femoral artery were ligated for 6 hours and then released (Group I). In controls, only preparation of these arteries without clamping were performed in 4 rats (Group II). In both groups, creatine phosphokinase (CPK), IL-8 and IL-10 were measured and compared. In group I, CPK was significantly higher than in Group II after the ligation and the reperfusion. After the reperfusion, IL-8 increased significantly, remaining at a high value in group I. The IL-10 of Group I also increased significantly and indicated high 6 hours after the reperfusion, however, it significantly decreased 12 hours after the reperfusion. These results suggests that the high value of IL-8, which is inflammation-linked cytokine, and the low level of IL-10, an anti-inflammatory cytokine, may prolong the systemic inflammatory response. The imbalance of these two kinds of cytokines may play an important role in the incidence of reperfusion injury and myonephropathic metabolic syndrome, which is a fatal complication after acute arterial occlusion disease.

We encountered a case of an infectious anastomotic aneurysm after surgery, of an abdominal aortic aneurysm associated with postoperative paraplegia. A 63-year-old woman underwent a first operation for an impending ruptured abdominal aortic aneurysm, and was discharged. Six months later, re-operation was performed because of an anastomotic aneurysm. An anti-anatomical bypass was also performed due to finding pus near the graft. She then developed paraplegia. Spinal cord damage is a very rare complication in surgery for an abdominal aortic aneurysm. The prevention of spinal cord damage is necessary in the reconstruction of arteries such as the internal iliac artery or inferior mesenteric artery. We feel that it is important for prevention of spinal cord damage, to do a bypass operation to reduce the period of arterial ischemia from the collaterals.

Between 1999 and 2004, 337 cardiovascular surgical procedures using cardiopulmonary bypass were conducted in our institution. Femoral arterial cannulation was performed in 130 cases (38.6%) and 3 of these cases, all men aged under 60, developed compartment syndrome in the ipsilateral leg. The ischemic time of the leg was between 240 and 294min. Two of them developed myonephropathic metabolic syndrome (MNMS) and underwent continuous hemodiafiltration. Two of the cases were ambulant on discharge from hospital but one died. Compartment syndrome and MNMS are serious complications, and must be prevented rather than treated. Young male patients are at increased risk of these complications, and are often reported in Japan. In order to prevent leg ischemia during femoral Cannulation, care should be taken not to disrupt deep femoral arterial flow (which is the collateral inflow) or superficial femoral arterial flow. When back flow from the profunda femoris artery is inadequate, peripheral perfusion should be performed to avoid leg ischemia.

It has been reported that the left internal thoracic artery (LITA) should be used for CABG when its free flow is more than 40-80ml/min. In the past 6 years, 120 cases of CABG have been performed in our institution. In 71 of these 120 cases, LITA was anastomosed to the left anterior descending coronary artery (LAD). These 71 cases can be divided into the following two groups: Group L consists of 14 cases, in which LITA-FF was less than 20ml/min. Group H consists of 57 cases, in which LITA-FF was 21ml/min or more. In all cases, LITA was dissected by electrocauterization. Papaverine administration and balloon dilation of LITA were not employed. We performed a comparison study between the groups based on post operative coronary angiographic findings. In group H, LITA graft occlusion was identified in 3 cases, and “string sign” in 7 cases. In group L, “string sign” was identified in only 1 case, and there was no LITA graft occlusion. There was no significant difference between the two groups. Satisfactory results of early graft patency were achieved as follows: 94.7% in group H, 100% in group L. These results suggest that LITA can be used for CABG, even when the free flow is less than 20ml/min.

We investigated the clinical results of coronary arterial bypass grafting (CABG), using a terminal warm blood cardioplegia (TWBCP) for myocardial preservation. In the past 6 years, 102 cases of CABG have been performed at our institution. These 102 cases were divided into the following two groups; (1) Group T, consisting of 41 cases, in which TWBCP was employed; (2) Group non-T, consisting of 61 cases, in which TWBCP was not employed. We performed a comparative study between the groups on the perioperative cardiac function and so on. Between the two groups, there were no significant differences in age, gender, preoperative ejection fraction (EF), operative time, cardiopulmonary bypass time (CPBT) and the level of CPK-MB. In group T, the number of grafts was significantly more than that in group non-T (p=0.002). Aortic cross-clamp time was significantly longer in group T. However, the duration of assisted circulation after aortic declamp was significantly longer in group non-T than that of group T (p=0.01). The incidence of ventricular fibrillation after release of aortic clamp in group T was 9.8%, while it was 67.2% in group non-T, showing a significant difference. Furthermore, the postoperative cardiac index in group T was significantly higher than that in group non-T. These results suggest that it is important for the myocardium, to recover from its ischemic damage caused by VF after release of aortic cross-clamp. In conclusion, we consider it effective to employ TWBCP in CABG to improve postoperative cardiac function.

Three cases of aortic dissection involving abdominal aortic aneurysms are reported. Two of the 3 cases died from intestinal necrosis. In one of them, the abdominal aortic aneurysm ruptured following aortic dissection. Fenestration was not performed at the proximal anastomosis in the operation, and it is thought that this resulted in occurrence of intestinal necrosis due to superior mesenteric artery obstruction. In the other non-survivor, aortic fenestration and graft replacement were performed. However, he died from descending-sigmoid colon necrosis due to internal iliac artery obstruction. An autopsy demonstrated no problem that with the graft anastomosis. The successful case of aortic fenestration and graft replacement had no postoperative complications. Since the aortic wall is fragile in acute aortic dissection, it is advisable that operation be conducted 1 month after the onset except in cases of aortic rupture and malperfusion syndrome. Fenestration, which is usually safe in chronic dissection, should be performed and it is desirable to fenestrate the aortic wall if possible even in acute dissection.

Reperfusion injury occasionally occurred after revasculization of acute arterial occlusion (AAO). The most common reason of death is myonephropatic metabolic syndrome due to reperfusion injury. This paper focusses on the criterion of systemic inflammatory response syndrome (SIRS). From January 1987 to April 1996, we treated 89 patients (male 59/female 30) with lower limb AAO. The mean age was 68.5 (ranging from 16 to 94) years old. There were 59 cases of thrombosis, 25 of embolism, 2 trauma and 3 dissecting aneurysm of the aorta. These patients were divided into two groups according to whether or not they fulfilled the criterion of SIRS. Of these patients, 46 cases met the criterion of SIRS (SIRS group) but the other 43 did not (non-SIRS group). We compared the two groups. The mortality of the SIRS group (23.9%) was higher than the non-SIRS group (2.3%). The ischemic time of the SIRS group (83.1±113.3 hours) was longer than the non-SIRS group (37.5±38.2 hours). Complications of MNMS were more common in the SIRS group (15.3%) than in the non-SIRS group (2.3%). The ischemic area in the SIRS group was remarkably less than in the non-SIRS group. Conclusion: The criterion of SIRS as indicated by the measurement of interleukin 8 (IL-8) was a useful prognostic parameter for limb salvage rate and mortality of AAO patients.

A 63-year-old man suffered from type A acute aortic dissection associated with descending thoracic aortic aneurysm and coronary stenosis. He was treated surgically 49 days after onset of acute aortic dissection. Deep hypothermic selective cerebral perfusion was carried out for brain protection. It revealed the aneurysm, 51mm in diameter, located just distal to the aortic arch, and an intimal tear of the dissection located posterior wall of aneurysm. The total arch was replaced with 24mm vascular graft and CABG (LITA-to-seg. 8) was carried out. The postoperative course was uneventful and he was discharged on the 18th postoperative day.