Nobuya Zenpo

Is endovascular treatment of abdominal aortic aneurysms less invasive regarding the biological responses

To compare the biological responses following an endoluminal repair and a conventional open repair of abdominal aortic aneurysm (AAA), 14 patients who underwent an endoluminal repair (endograft group) and 26 who underwent an open repair (open group) were investigated. As markers of biological responses, interleukin-6 (IL-6) and -8 (IL-8), granulocyte elastase (GEL), white blood cell count (WBC), and serum C-reactive protein (CRP) were all measured preoperatively as well as on postoperative days (POD) 1, 3, and 6. In addition, the blood loss, duration of surgery, initial oral intake the day after surgery, and length of hospital stay were compared between both groups. The plasma levels of IL-6, GEL, CRP, and WBC were higher in the endograft group than in the open group, while the CRP, WBC, and GEL levels all peaked on POD 3. The plasma level of IL-6 remained high in the endograft group, compared with that in the open group throughout the study period. Conversely, blood loss, initial oral intake the day after surgery, and the length of hospital stay were all significantly greater in the open group than in the endograft group, although there was no significant difference in the duration of surgery between the two groups. These findings indicate that although the endoluminal repair of AAA is supposed to be less invasive, the biological responses tend to be greater because of the manipulation related to the insertion of the stent graft.

Changes in Left Ventricular Function after Cardiac Arrest and Reperfusion in Hypertropheral Hearts

Hypertrophied hearts may be more susceptible to ischemia/reperfusion during cardiac surgery than normal hearts, so we designed to compare the alterations in left ventricular function after ischemia/reperfusion, in hypertrophied hearts (Group H) with those in normal hearts (Group C), using a rabbit heart model of hypertrophy induced by banding of the ascending thoracic aorta. The pre and postischemic left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), positive and negative dP/dt, and coronary flow were measured. The percent recovery of coronary flow and negative dP/dt were significantly lower in Group H than in Group C (p < 0.05). The LVEDP was significantly greater in Group H, and the LVEDP increased significantly from the base line value in Group H (p < 0.05). There was no significant difference in other value between two groups. These findings demonstrated that LV diastolic dysfunction rather than LV systolic dysfunction occurred in the early ischemic stage, especially to hypertrophied hearts, indicating that better protection is required for these hearts.

Aneurysms of the descending aorta: Surgical experience with three methods of adjunct procedures

Thirteen patients were surgically treated for the repair of aneurysms of the descending aorta, using three different types of adjunct procedures—an external temporary bypass with a vascular prosthesis, a tridodecylmethylammonium chloride (TDMAC) or a partial cardiopulmonary bypass. There was no operative death, though one patient died 73 days following surgery. Significant intraoperative morbidity occurred in 3 patients: one had ventricular fibrillation and the other two massive hemorrhages. There was no instance of paraplegia or renal failure. The only significant complication that developed was pulmonary insufficiency in two patients with a pump bypass. The mean operative time and the mean aortic occlusion time in patients with the TDMAC shunt were shorter than the times in patients with the vascular prosthetic shunt or the pump bypass. TDMAC shunt required no special equipment and cannulation was simpler and safer.

Does Minimally Invasive Endovascular Grafting for Abdominal and Thoracic Aortic Aneurysms Induce Less Inflammatory Response

This study was conducted to investigate whether minimally invasive endovascular grafting (EG) for abdominal (AAA) and thoracic (TAA) aortic aneurysms induces less inflammatory response. Of 27 patients with AAA, 15 underwent conventional open surgery (AAA-C) and 12 underwent EG (AAA-E). Of 22 patients with TAA, 13 underwent conventional open surgery under total cardiopulmonary bypass with deep hypothermia or partial cardiopulmonary bypass with normothermia (TAA-C), and 9 underwent EG (TAA-E). Body temperature (BT), white blood cell (WBC) count, C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-8 (IL-8), and granulocyte elastase (GEL) were measured preoperatively, immediately after the operation, and on postoperative days (PODs) 1, 3, and 6. The intraoperative blood loss was significantly less, oral intake was recommenced significantly earlier, and the postoperative hospital stay was significantly shorter in the AAA-E and TAA-E groups than in the AAA-C and TAA-C groups. The BT in the AAA-E group was elevated from immediately after the operation until POD 2. Moreover, WBC count, CRP, and IL-6 were significantly higher in the AAA-E group, from POD 1 to POD 3, on POD 6, and on POD 3, respectively. However, IL-8 and GEL did not differ between the two groups. On the other hand, the BT in the TAA-E group was significantly higher than that in the TAA-C group from POD 1 to POD 4. The CRP was significantly higher in the TAA-E group from POD 3 to POD 6; and IL-6, IL-8, and GEL were higher in the TAA-C group immediately after the operation. Patients in the TAA-C group had more morbidity due to respiratory failure and cerebral infarction postoperatively. We conclude that although EG for TAA and AAA is minimally invasive it induces a significantly more severe inflammatory response, especially in patients with AAA.