Surgical repair of coronary arteriovenous fistula: a simple and useful approach to identify the fistulous communication.

In repairing coronary arteriovenous fistula (CAVF), it is very important to interrupt the fistulous tract without compromise of normal coronary vessel flow. In our case, selective coronary arteriography showed that the CAVF from the left anterior descending coronary artery (LAD) was very close to the native coronary artery and had a very broad and short neck. We describe a simple and useful approach, by using both antegrade and retrograde coronary perfusion, that makes it possible to certainly protect myocardium and to clearly distinguish the normal native coronary artery from the fistulous tract.     

Isolated Coccygeal Tuberculosis

Isolated tuberculosis of the coccyx is extremely rare. A 35-year-old man presented with a 3-month history of coccygeal and gluteal pain. Computed tomography and magnetic resonance imaging revealed osseous destruction and a large enhancing mass involving the coccyx with anterior and posterior extension. Pathologic examination of the surgical specimen revealed necrosis, chronic granulomatous inflammation, and multinucleated giant cells consistent with tuberculosis. This case highlights the importance of considering tuberculosis as a diagnosis even though unusual sites are involved.     

Early sexual maturation,central adiposity and subsequent overweight in late adolescence. A four-year follow-up of 1605 adolescent Norwegian boys and girls: the Young HUNT study

Background  

Early sexual maturation has been associated with overweight that may persist after the completion of biological growth and development. We have prospectively examined the influence of early sexual maturation on subsequent overweight in late adolescence and assessed if this association was modified by central adiposity in early adolescence.     

Preserved endothelial vasomotion and fibrinolytic function in patients with acute stent thrombosis or in-stent restenosis

Introduction: Acute stent thrombosis and in-stent restenosis are serious complications of percutaneous coronary intervention (PCI) and may be associated with vascular or platelet abnormalities. We aimed to assess endothelium-dependent vasomotion, endogenous fibrinolysis and platelet function in patients with acute stent thrombosis or in-stent restenosis. Materials and methods: Thirty-six subjects were enrolled into four groups: acute stent thrombosis, in-stent restenosis, uncomplicated PCI with stent implantation and healthy matched controls. Forearm blood flow was measured using bilateral venous occlusion plethysmography during intra-brachial acetylcholine, substance P and sodium nitroprusside infusion. Venous blood samples were withdrawn for estimation of plasma fibrinolytic variables and platelet aggregometry. Results: Acetylcholine, substance P and sodium nitroprusside caused dose-dependent increases in blood flow (P<0.001) and substance P caused a dose-dependent increase in tissue-type plasminogen activator (t-PA) release (P<0.001) in all groups. Thrombin, collagen, adenosine diphosphate (ADP) and the thromboxane A2 analogue, U46619, caused dose-dependent platelet aggregation (P<0.001) in all groups. There were no significant between group differences in these responses except that, in keeping with aspirin therapy, collagen-induced platelet aggregation was impaired in patient groups compared with healthy controls (P<0.01). Post-hoc analysis demonstrated a significant impairment of acute t-PA release in current smokers compared to non-smokers (P<0.05). Conclusions: Despite previous reports suggesting impaired vascular function, endothelium-dependent vasomotion, endogenous fibrinolysis and platelet aggregation do not appear to play a major role in the pathogenesis of acute stent thrombosis or in-stent restenosis.     

Preoperative Staging of Rectal Cancer With MRI: Accuracy and Clinical Usefulness

Background: Preoperative staging is essential for planning of optimal therapy for patients with rectal cancer. Recently, magnetic resonance imaging (MRI) is used frequently because of its benefits of clear pelvic image are better than other diagnostic methods. The purpose of this study was to determine accuracy rates and clinical usefulness of MRI in preoperative staging of rectal cancer.Methods: Between February, 1997, and December, 1999, 217 patients with histologically proven rectal cancer were staged preoperatively and had surgical resections performed. MRI criteria for depth of invasion was determined by the degree of disruption of the rectal wall. Metastatic perirectal lymph nodes were considered to be present if they showed heterogenous texture, irregular margin, and enlargement (.10 mm).Results: The accuracy of the MRI for determining depth of invasion was 176/217 (81%) and regional lymph node invasion was 110/217 (63%). In the T stage, accuracy rate of T1 was 3/4 (75%), T2 was 20/37 (54%), T3 was 141/162 (87%), and T4 was 12/14 (86%), respectively. The specificity of lymph node invasion was 45/110 (41%) and the sensitivity was 91/107 (85%). The accuracy rate of regional lymph node involvement was 136/217 (63%). T1 and T2 were overstaged in 1/4 (25%) and 17/37 (46%), respectively, and T3 was understaged in 15/162 (9.2%). The accuracy rate to detect metastatic lateral pelvic lymph node was 4/14 (29%) after lateral pelvic lymph node dissection was done in 14 patients under MRI. The accuracy rate in assessing levator ani muscle tumor involvement was 8/11 (72%).Conclusions: MRI showed a good, comparable accuracy rate for determining depth of tumor invasion, compared with transrectal ultrasonography, which still has a low accuracy rate for detecting metastatic lymph node. MRI with endorectal coil may increase the accuracy rate of T1 and T2 lesions. In addition, clear sagittal and coronal sectional pelvic images can give a lot of information about adjacent organ invasion or any invasion of levator ani muscle. MRI can be useful for choosing an appropriate extent of lymph node dissection and type of surgery.     

A novel S-nitrosothiol (RIG200) causes prolonged relaxation in dorsal hand veins with damaged endothelium

BACKGROUND: Reduced nitric oxide bioavailability caused by endothelial dysfunction or damage is a contributory factor in the initiation and progression of a number of cardiovascular diseases. Delivery of exogenous nitric oxide is an attractive therapeutic option, but current agents lack selectivity for areas of endothelial damage. We tested the hypothesis that a novel nitric oxide donor drug, N-(S-nitroso-N-acetylpenicillamine)-2-amino-2-deoxy-1,3,4,6-tetra-O-acet yl-P-glucopyranose [RIG200], which has selective effects in endothelium-denuded isolated arteries in vitro, would exert similar effects in dorsal hand veins with experimentally damaged endothelium in vivo. METHODS: Venodilator responses to sodium nitroprusside and RIG200 were compared in two groups of healthy volunteers (age range, 18 to 63 years; n = 7 for each group) in norepinephrine 70% maximum effective concentration (EC70) preconstricted hand veins with use of the Aellig technique. In this doubleblind study, subjects were randomly assigned to receive either sodium nitroprusside or RIG200 (infusions of 0.06 and 6 nmol/min into the hand vein) before and 2 days after 15 minutes of local venous irription with distilled water. Endothelial function was assessed in all subjects on both visits with use of the endothelium-dependent vasodilator acetylcholine (1 nmol/min). RESULTS: Irrigation of hand veins with distilled water abolished endothelium-dependent dilatation in response to acetylcholine in both study groups (n = 14) but did not affect the amplitude or duration of responses to the conventional nitric oxide donor sodium nitroprusside (P = .87; n = 7). However, responses to RIG200 were significantly prolonged during the washout phase (30 minutes) in veins after water irrigation (P = .02; n = 7). CONCLUSION: These studies confirm that RIG200 has prolonged effects in veins with damaged endothelium, a characteristic that might be exploited therapeutically to target nitric oxide delivery to damaged blood vessels.     

Novel S-nitrosothiols do not engender vascular tolerance and remain effective in glyceryl trinitrate-tolerant rat femoral arteries

Organic nitrates, such as glyceryl trinitrate, are nitric oxide (NO) donor drugs that engender tolerance with long-term use. Here, we tested the hypothesis that our novel S-nitrosothiols, N-(S-nitroso-N-acetylpenicillamine)-2-amino-2-deoxy-1,3,4,6, tetra-O-acetyl-beta-D-glucopyranose (RIG200) and S-nitroso-N-valeryl-D-penicillamine (D-SNVP), do not induce vascular tolerance ex vivo. Femoral arteries from adult male Wistar rats were preconstricted with phenylephrine and perfused with the NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME). Perfusion pressure was measured during 20-h treatment with supramaximal concentrations of NO donor (10 microM). Perfusion with glyceryltrinitrate caused a vasodilatation, which recovered over 2-20 h. In contrast, the S-nitrosothiols caused vasodilatations that were maintained throughout the 20-h perfusion period. Responses to S-nitrosothiols were partially reversed by the NO scavenger ferrohaemoglobin and fully reversed by the soluble guanylate cyclase inhibitor [1H-[1,2,4] oxadiazole [4,3-a]quinoxaline-1-one (ODQ). Glyceryltrinitrate-tolerant vessels were fully responsive to bolus injections of S-nitrosothiols. Resistance to tolerance is an attractive property of our novel compounds, particularly in view of their sustained activity in arteries with damaged endothelium.