Norihide Sugano

Effects of human atrial natriuretic peptide on renal function in patients undergoing abdominal aortic aneurysm repair.

Objective:Ischemia-reperfusion injury is an important cause of renal dysfunction after abdominal aortic aneurysm repair. Human atrial natriuretic peptide (hANP) is a potent endogenous natriuretic, diuretic, and vasorelaxant peptide. The objective of the present study was to evaluate the effects of hANP on renal function in patients undergoing abdominal aortic aneurysm repair. Design:A prospective, randomized, placebo-controlled study Setting:Intensive care unit of a university hospital. Patients:Forty patients undergoing elective abdominal aortic aneurysm repair. Interventions:The patients were randomized to receive a continuous infusion of either hANP (0.01–0.05 &mgr;g/kg/min) (n = 20) or placebo (n = 20) immediately before aortic cross-clamping. The infusion of hANP or placebo continued for 48 hrs. Measurements and Main Results:Blood and urine samples were taken before surgery, at admission to the intensive care unit, and on days 1, 2, and 3 postoperatively, for measurement of serum concentrations of sodium, creatinine, and blood urea nitrogen and plasma concentrations of ANP and brain natriuretic peptide (BNP). Urine volume and urinary concentrations of N-acetyl-&bgr;-D-glucosaminidase (NAG), sodium, and creatinine were also measured. The mean plasma concentration of ANP was significantly higher in the hANP group than in the placebo group. The mean plasma BNP concentration was significantly lower in the hANP group than in the placebo group. The mean serum concentrations of creatinine and blood urea nitrogen were significantly (p < .05) lower in the hANP group than in the placebo group. The mean urine volume and mean creatinine clearance were significantly (p < .05) higher in the hANP group than in the placebo group. The mean urinary NAG/creatinine ratio was significantly (p < .05) lower in the hANP group than in the placebo group. Conclusions:The intraoperative and postoperative infusion of low-dose hANP preserved renal function in patients undergoing abdominal aortic aneurysm repair. Further studies are needed to assess the efficacy of prophylactic hANP infusion on perioperative renal outcome.

A Quantitative Method for Evaluating Local Perfusion Using Indocyanine Green Fluorescence Imaging

BACKGROUND The purpose of this study is to introduce a new method, indocyanine green fluorescence imaging (ICG-FI), as an adjunct to distal pressure measurements in patients with peripheral arterial disease and symptomatic lower limb ischemia. METHODS A total of 34 patients with peripheral arterial disease, including 11 with claudication (Fontaine II), 7 with rest pain (FIII), and 16 with an ulcer or gangrene (FIV), were enrolled. After an intravenous injection of ICG (0.1 mg/kg), foot perfusion was recorded by an infrared light camera. Fluorescence intensity was plotted on a time-intensity curve using recorded images, allowing the calculation of new parameters. Severity of ischemia was assessed as the duration between the rising point and half value of maximum brightness (T½). The difference in the fluorescence intensity between 10 seconds after the rising point and baseline (PDE10) was compared with the transcutaneous oxygen pressure (tcPO2) at the same site (n=51). RESULTS Median T½ was 23 seconds in FII, 41 seconds in FIII (P<0.05), and 17 seconds in FIV patients. PDE10 correlated moderately with tcpO2 (r2=0.5). A cut-off value (PDE10=28) predicted a critically ischemic limb (FIII and FIV), defined as tcpO2<30 mm Hg with a sensitivity of 100% and specificity of 86.6%. CONCLUSIONS Local tissue perfusion can be quantitatively evaluated by using ICG fluorescence imaging. It is a safe, fast, noncontact method of imaging, which may be useful even at the ulcer itself and in the circumferential area.

Differential detection rate of periodontopathic bacteria in atherosclerosis

PurposePeriodontitis has been associated with atherosclerotic cardiovascular lesions. There may be a link between periodontopathic bacterial infection and atherosclerosis.MethodsIn 53 patients with atherosclerosis, periodontal disease was classified according to the probing depth of the periodontal pocket. To compare the detection rate in different arterial lesion, specimens of diseased arteries (10 primary atherosclerotic lesions, 43 anastomotic lesions) and 21 control arteries without atherosclerotic findings macroscopically and microscopically in the arterial wall, obtained during the surgical procedures were examined for the presence of five species of putative periodontal bacteria using polymerase chain reaction (PCR) analysis.ResultsFifty-one of the 53 patients (96%) had periodontitis, and 34 (64%) of those patients had severe periodontitis or were edentulous. In total, PCR analysis detected DNA specific for periodontal bacteria in 28 of the 53 specimens (52%) of atherosclerotic arterial wall. Only 5 of 21 (23%) were detected in control specimens.ConclusionsA high percentage of periodontopathic bacteria were detected in atherosclerotic arterial wall specimens from patients with atherosclerosis, especially with primary atherosclerotic lesions, and most cases had severe periodontitis.

Effects of Acupressure on Lower Limb Blood Flow for the Treatment of Peripheral Arterial Occlusive Diseases

PurposeTo investigate the effects of acupressure on lower limb blood flow for the treatment of peripheral arterial occlusive diseases (PAOD).MethodsFrom February 2004 to February 2005, 30 patients with stage II PAOD underwent measurements of the lower limb blood flow. Six patients (group A) were assigned as controls without any acupoint stimulation, while 24 (group B) underwent stimulation at acupoints by acupressure. The acupoints Yanglingquan (GB34), Zusanli (ST36), Yinlingquan (SP9), and Sanyinjiao (SP6) of the symptomatic lower limbs were stimulated for 3 min. Transcutaneous oximetry (tcPO2) was used to determine the blood flow of the chest wall, bilateral distal crura, and bilateral dorsa of the foot before and during the stimulations at the acupoints.ResultsGroup A showed no significant change in the lower limb blood flow. In group B, the tcPO2 values of chest wall, bilateral distal crura, and the dorsum of foot of the stimulated lower limb increased significantly during acupressure (P < 0.01), whereas no significant change was shown in the dorsum of the foot of the non-stimulated lower limb. Moreover, the blood flow of the lower limbs that had undergone an ipsilateral sympathectomy increased significantly (P < 0.01).ConclusionsAcupressure was found to cause significant increases in the lower limb blood flow of stage II PAOD patients. This treatment modality may therefore be effective for improving the symptoms of such patients.

Surgical technique for management of Takayasu’s arteritis

Anastomotic aneurysm may occur after surgical treatment of Takayasus arteritis. We describe a surgical technique designed to prevent this problem. The technique includes a bypass from a donor artery to a nondiseased distal artery, reinforcement of the suture line to prevent stretching or expansion at the anastomoses, and minimization of inflow perfusion to the brain. The technique was used in two patients, whose grafts were patent 1 and 2 years, respectively, after surgery. Careful differential diagnosis is essential to the success of this method, which may also be used to treat aortic aneurysm resulting from Behcets disease but which is not appropriate for mid-aortic syndrome or Buergers disease.

Tumor thrombectomy without bypass for low-grade malignant tumors extending into the inferior vena cava: report of two cases.

Endometrial stromal sarcoma (ESS) rarely extends into the inferior vena cava (IVC). Two cases of ESS extending into the IVC were encountered. In the first case a low-grade sarcoma and cavography revealed the tumor thrombus to extend to just below the left renal vein from the right internal iliac vein, and the IVC was patent. A tumor thrombectomy was accomplished to prevent pulmonary embolism (PE) and to achieve a good prognosis. The second case was also a low-grade sarcoma. Abdominal computed tomography scanning revealed a large thrombus extending into the IVC just below the hepatic vein. A tumor thrombectomy with an IVC resection was performed. The postoperative course was uneventful for both cases. Aggressive surgical treatment is thus recommended to excise a tumor thrombus with or without an IVC resection in patients with ESS of low-grade malignancy extending into the IVC to prevent sudden death due to PE.

Long-Term Results of Aorta-Superior Mesenteric Artery Bypass Using a New Route

PurposeSeveral methods of revascularization after mesenteric ischemia have been proposed. Using a new route, we performed retrograde loop bypass grafting to the superior mesenteric artery (SMA) with a ringed expanded polytetrafluoroethylene (ePTFE) graft.MethodsWe anastomosed the graft to the infrarenal aorta, which ran behind the left renal hilum, turned ventral, and was anastomosed to the SMA in an antegrade fashion hemodynamically. Five patients underwent this procedure, which resulted in remarkable symptomatic relief.ResultsThere were no postoperative deaths or serious complications, although some patients suffered paralytic ileus. All of the grafts remained patent during long-term follow-up, ranging from 17 to 72 months (mean: 37.8 months). Postoperative angiograms showed good configuration of the graft, which did not compress the renal vessels.ConclusionInfrarenal aorta-SMA bypass relieved mesenteric ischemia and achieved good long-term graft patency. Thus, we consider it to be an effective and durable vascular procedure to reduce postoperative mortality and morbidity.

Maggot Debridement Therapy for Peripheral Arterial Disease

INTRODUCTION Maggots are potent debriding agents capable of removing necrotic tissue and slough; however, it is still unclear which wounds are most likely to benefit from maggot debridement therapy (MDT). Thus, we performed this retrospective review to gain insight into the patient and therapy characteristics influencing outcome. PATIENTS AND METHODS We reviewed patients with foot ulcers caused by critical limb ischemia, encountered during the period between June 2005 and May 2010. The treatment outcomes were defined as effective or ineffective. RESULTS There were 16 patients with 16 leg ulcers. The patients were 13 men and 3 women, with an average age of 67.2 years (range, 47-85 years). Ten (63%) of the 16 ulcers were treated effectively. According to univariate analyses, an ankle brachial pressure index (ABI) lower than 0.6 (p = 0.03) had a negative impact on the outcome of MDT; however, outcome was not influenced by gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, smoking, or laboratory findings. CONCLUSIONS Some patient characteristics, such as gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, and smoking, do not seem to contraindicate eligibility for MDT. However, a limb with an ABI lower than 0.6 is less likely to benefit. (English Translation of J Jpn Coll Angiol 2011; 51: 209-213.).

Vascular laboratory for critical limb ischaemia.

This is a narrative review on vascular assessment for critical limb ischaemia in the past and present combining Finnish and Japanese experience.

Drainage Surgery Followed by Postoperative Irrigation with Gentian Violet for Prosthetic Graft Infection Caused by Methicillin-resistant Staphylococcus aureus

INTRODUCTION Infection of a prosthetic graft is still associated with considerable morbidity and mortality. Conventionally, this vascular complication is treated by excising the infected graft, although prosthetic graft preservation is possible in selected cases. REPORT We report the successful treatment of prosthetic graft infection caused by methicillin-resistant Staphylococcus aureus (MRSA) in three patients, by performing drainage surgery with postoperative irrigation using gentian violet. DISCUSSION The combination of drainage surgery and irrigation with gentian violet solution provides an alternative option to graft excision for prosthetic graft infection.