We described a simple technique for calibrating an aneurysmal dilatation on a saphenous vein graft (SVG). The SVG with segmental dilatation is passed through a short section of the saphenous vein, and the dilatation is covered by the short cylinder of the vein. Both parts are fixed by arterial pressure, which expands the SVG. This technique was used in three SVG in three patients who underwent coronary artery bypass grafting. The patency without dilatation was confirmed by angiography one year after surgery in two patients. This simple method is feasible to repair an aneurysmal dilatation on the SVG.

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We report the success rate of endovascular therapy (EVT) using a hydrophilic-coated 4.5-Fr low-profile sheathless guiding catheter (Parent Plus45^TM; Medikit, Tokyo, Japan) for the infrapopliteal artery by the cross-over approach. Between April 2009 and May 2010, we performed EVT using the Parent Plus45^TM for infrapopliteal arteries in 22 lesions in 17 limbs for critical limb ischemia (CLI). This was performed in 15 patients using the cross-over approach. Delivery of the Parent Plus45^TM to the popliteal artery of all the patients with CLI who underwent the procedure was successful. The lesion success rate was 95% and the initial success rate was 100%. There were no complications noted. EVT using a 4.5-Fr sheathless guiding catheter for the infrapopliteal artery by the cross-over approach has the potential for a less invasive strategy for the treatment of CLI.

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The purpose of this study was to evaluate the outcomes of open abdominal aortic aneurysm (AAA) repair in patients aged over 85 years. Between October 2002 and September 2010, 21 patients (4.8%) underwent open AAA repair at our institute. The mean age of the patients was 87.2 years (range, 85–92 years). Ten patients (47.6%) underwent emergency operation. Ruptured AAA was diagnosed in 7 patients (33.3%). The mean aneurysm size was 68.9 mm. The operative mortality was 23.5% and this was observed in 5 patients. All of them had ruptured AAA with preoperative shock. Operative mortality was not observed in cases of elective operation. The mean duration of postoperative hospital stay was 22.3 days. Survival rates of all patients were 85.1% at 1 year and 74.5% at 3years. The outcomes of elective open AAA repair in patients aged over 85 years were acceptable.

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Spontaneous visceral artery dissection without aortic dissection is rarely encountered. Furthermore, there is no consensus regarding the pathology or optimal therapy related to this problem. This report details six cases of isolated visceral artery dissection. Patients evaluated included five men and one woman with a mean age of 51 years. Of these cases, three presented with celiac artery (CA) dissection, two presented with superior mesenteric artery (SMA) dissection, and one presented with CA, SMA, and bilateral renal artery (RA) dissection. All patients complained of severe abdominal pain and were diagnosed by contrast-enhanced computed tomography. All cases received conservative treatment including antihypertensive therapy. Among the six patients, four were hospitalized and the other two were treated at an outpatient clinic. No patients developed organ ischemia or aneurysm enlargement during follow-up.

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A 57-year-old woman who had undergone replacement of the ascending aorta more than 20 years ago previously complained of abdominal pain. Computed tomography revealed a giant retrosternal anastomotic aneurysm, for which we decided to perform urgent surgery. Cardiopulmonary bypass was established and cooling was started before resternotomy. Use of aortic occlusion catheter and left ventricle vent kept the surgical field clear. We completed the reconstruction of the ascending aorta safely.

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Pulmonary O₂ uptake (VO₂) increases almost linearly during incremental cycling exercise, whereas deoxygenation of the vastus lateralis muscle (VL), measured by near-infrared spectroscopy, develops continuously and then attenuates before reaching VO₂ peak (VO_2peak). The mechanisms behind these are unclear. In previous studies, it was speculated that muscle deoxygenation reached maximal deoxygenation or that the attenuation was led by the recruitment of fast twitch muscle fibers. However, these theories were not supported by studies using arterial occlusion method or surface electromyography. In contrast, the changes of body posture and inspired O₂ fraction during the exercise influenced the intensity of attenuation of muscle deoxygenation, suggesting that the attenuation of muscle deoxygenation was partly related to muscle circulation, muscle metabolism, or both. One question was why VO₂ increases almost linearly until VO_2peak despite the plateau of muscle deoxygenation. One of the hypotheses was that deoxygenation of the working muscles other than VL might compensate for that of VL. In fact, deoxygenation of the rectus femoris muscle developed at high intensity. These results suggested that attenuation of muscle deoxygenation was partly related to muscle circulation, muscle metabolism, and the balance among deoxygenation of the other working muscl

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Abstract: In order to better understand the pathophysiology of cardiovascular diseases, both peripheral muscle metabolism and blood flow should be examined. Conventionally, blood flow measurements were performed by venous occlusion plethysmography or catheter based procedures, which evaluate non-selective blood flow. Plethysmography measures the whole limb blood flow, including the flow in skin and non-exercising muscles. A catheter is usually inserted into the large vein and also provides the whole limb blood flow measurement. In contrast, near-infrared spectroscopy might provide information about the nutritive flow in localized exercising muscle. A combined use of NIRS with ³¹P-magnetic resonance spectroscopy, which can measure muscle metabolism, is a novel tool to elucidate the pathophysiology in cardiovascular disorders.

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The purpose of this study was to evaluate the heterogeneity of muscle oxygen consumption (VO₂mus) and muscle oxygenated hemoglobin/myoglobin content (Hb/MbO₂) in the right thigh during stepwise incremental cycling exercise in supine position. Subjects were five healthy male volunteers (30±2 yrs., height 175.0±1.9 cm, weight: 67.3±3.1 kg). Muscle oxygenation in the right thigh was measured using multi-channel near infrared continuous wave spectroscopy (multi-NIRcws). In order to reduce the influence of the hydrostatic pressure within multi-NIRcws measurement sites, the subjects performed the stepwise incremental cycling exercise while lying on a bed in a supine position. The exercise load was started at 30 watts and increased by 30 watts every 4 minutes until the subjects reached exhaustion. We evaluated VO₂mus and Hb/MbO₂ at rest and during each exercise load. VO₂mus increased and Hb/MbO₂ decreased with the increase exercise load in all measurement sites. VO₂mus at high intensity exercise load was significantly larger in the proximal positions than in the distal positions (p<0.05). Hb/MbO₂ showed no significant differences in all measurement sites at rest and during all exercise loads. These results indicated the heterogeneity of VO₂mus and oxygen supply toward a longitudinal direction between proximal and distal positions at high intensity exercise load.

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We estimated the correlation between recovery time (RT) of lower limb ischemia after walking exercise as measured by near-infrared spectroscopy (NIRS) and prognosis of cardiovascular ischemic events in patients with arteriosclerosis obliterans (ASO). Twenty-two patients were examined and the mean follow-up period was 9.2±2.1 years. The patients in whom cardiovascular events occurred (group E: n=10; 45.5%) and those in whom cardiovascular events did not occur (group N: n=12; 55.5%) showed no significant difference in RT, but the RT in the lower limb of patients with severe ischemia was longer in group E than in group N (208.1±37.0 sec vs. 146.8±33.8 sec). RT measured by NIRS may be useful as a prognostic predictor of cardiovascular events in patients with ASO.

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