Search results for "Constriction"
showing 10 items of 254 documents
Cryoplasty versus angioplasty in the treatment of arterial restenosis in an experimental model of atherosclerosis in rabbits
2014
Abstract Cryoplasty may reduce the incidence of post-angioplasty restenosis in peripheral atherosclerotic arteries. Our study is looking to investigate the mid-term effects (4 weeks) of an FDA-approved cryoplasty catheter (PolarCath®, Boston Scientific) compared to a conventional angioplasty catheter using a hypercholesterolemic rabbit model of arterial restenosis based on diet plus vessel injury. Thirty-six normolipidemic, 3-month old male New Zealand White rabbits were used. Balloon angioplasty was performed on left external iliac arteries on day 1. Animals were fed with a hypercholesterolemic diet for 60 days. On day 120, three groups of animals were established: conventional PTA (percut…
Detection of flap venous and arterial occlusion using interstitial glucose monitoring in a rodent model.
2010
Background: Free tissue transfer necessitates vigilant postoperative monitoring for vessel occlusion. Unfortunately, most monitoring methods require experienced personnel and are expensive to use. Furthermore, many tests have low sensitivity, low specificity, or significant delay between vessel occlusion and detection. The authors report on a novel method of tissue monitoring that avoids these limitations by tracking interstitial glucose concentration. Methods: Vertical rectus abdominis myocutaneous flaps were elevated in adult rats based on the superior epigastric vessels. Interstitial glucose within the flaps was monitored using a transcutaneous sensor. Interstitial glucose was recorded f…
Experimental diabetes induces hyperreactivity of rabbit renal artery to 5-hydroxytryptamine.
2002
Abstract The influence of diabetes on the response of isolated rabbit renal arteries to 5-hydroxytryptamine (5-HT) was examined. 5-HT induced a concentration-related contraction that was higher in arteries from diabetic rabbits than in arteries from control rabbits. Endothelium removal did not significantly modify 5-HT contractions in arteries from control rabbits but enhanced the response to 5-HT in arteries from diabetic rabbits. Incubation with N G -nitro- l -arginine ( l -NA) enhanced contractions to 5-HT in arteries from control and diabetic rabbits. In arteries with endothelium, this l -NA enhancement was lower in diabetic rabbits than in control rabbits. In arteries without endotheli…
Subclavian Stenosis/Occlusion in Patients with Subclavian Steal and Previous Bypass of Internal Mammary Interventricular Anterior Artery: Medical or …
2004
There are only a few published studies on the association between subclavian steal syndrome and ischemic heart disease. The objective of this report is to evaluate the efficacy of subclavian stenoocclusion treatment in patients with subclavian steal syndrome (SSS) and previous cor- onary bypass. Over the last 8 years we observed 207 patients who underwent left internal mammary artery–intraventricular artery (LIMA–IVA) bypass graft. Of these, 31 patients were affected by steno-occlusion of the homolateral subclavian artery. Ten patients (group 1) showed latent vertebral-SSS and were pharmacologically treated. Seven patients (group 2) had an intermittent vertebral-SSS; four patients were trea…
A minimally invasive approach for aortobifemoral bypass procedure
2011
Surgical aortobifemoral bypass procedure for aortoiliac occlusive disease remains the gold standard treatment despite rapidly expanding range of indications for endovascular repair. Besides several disadvantages such as dysparaesthesias, hernias, and unpleasant outcome, transperitoneal exposure of the aorta is also associated with operative autonomic nerve injury. In five male patients, infrarenal aorta was exposed through a small (8 cm) supraumbilical midline incision. Incision of the posterior peritoneum above the infrarenal aorta was limited to 3 cm. A 1 cm infraumbilical incision allowed transperitoneal placement of the distal aortic clamp outside of the operative field. Four centimeter…
The DETOUR procedure: no more need for conventional bypass surgery?
2018
Background Long segment occlusive disease in the superficial femoral artery remains a treatment challenge despite advances in open surgical and endovascular approaches. We report initial clinical results of an entirely new procedure to perform percutaneous femoro-popliteal bypass using the DETOUR System. First-in-human patients were performed in New Zealand from December 2013 to June 2014. After modifications to the technique and devices had significantly refined the procedure, the Detour I Trial commenced. Methods Review of initial results in the first five patients treated at a single site enrolled in IRB-approved, prospective clinical study using the DETOUR System. All patients signed in…
Effects of a nitrate-free interval on tolerance, vasoconstrictor sensitivity and vascular superoxide production
2000
Abstract OBJECTIVES In the present study, we tested whether a nitrate-free interval is able to prevent increases in vascular superoxide (O2•−) and the development of hypersensitivity to vasoconstrictors and whether this may result in restoration of vascular nitroglycerin (NTG) sensitivity. BACKGROUND Intermittent NTG-patch treatment (12 h patch on/patch off) has been shown to increase ischemic periods in patients with stable coronary arteries, suggesting a rebound-like situation during the patch-off period. Recently, we demonstrated that long-term treatment with NTG induces tolerance, which was in part related to increases in vascular O2•− and increased vasoconstrictor sensitivity. METHODS …
Trans-popliteal hybrid retrograde technique for revascularization of chronic total occlusions of the superficial femoral artery.
2020
Objectives We present the technical description and preliminary results of a hybrid approach for the treatment of chronic total occlusions of superficial femoral artery in the setting of critical limb-threatening ischemia (CLTI). Methods A retrospective analysis of selected case series was performed. A trans-popliteal hybrid technique was carried out in seven limbs (six patients). Open exposure of above-the-knee popliteal artery was performed over its maximum calcification zone. After retrograde recanalization and graft-stenting of the entire superficial femoral artery, endarterectomy of the popliteal artery was performed for debulking and widening of the distal landing zone of the endopros…
Pharmacological profile of phytoestrogens in cerebral vessels: in vitro study with rabbit basilar artery.
2003
As a previous step to consider their use in the pharmacology for stroke, we investigated the effects of four phytoestrogens (i.e. genistein, daidzein, zearalanone and biochanin A) on cerebral vessels. Cerebral vascular responses were analyzed by conventional recording of isometric tension in rabbit basilar artery segments kept in organ bath under standard conditions. The four phytoestrogens elicited concentration-dependent relaxant responses of different potency in basilar artery segments previously contracted with either 5x10(-2) M KCl or 10(-4) M UTP. Neither endothelium removal, 10(-4) M N(omega)-nitro-L-arginine methyl ester (L-NAME, nitric oxide (NO) synthase inhibitor), 10(-5) M1 H-[1…
Increased responsiveness of human pulmonary arteries in patients with positive bronchodilator response.
1996
Abstract 1. The effects of noradrenaline, endothelin-1, acetylcholine and sodium nitroprusside were studied in isolated pulmonary arteries obtained from 14 patients undergoing lobectomy for lung carcinoma. Seven patients had shown increased response to a bronchodilator test prior to operation. In the remaining patients (control) the bronchodilator test was negative. 2. Artery rings from patients with a positive bronchodilator response showed greater contraction to noradrenaline (pD2 = 6.44 +/- 0.1; Emax = 93 +/- 9% of response to 100 mM KCl) and endothelin-1 (pD2 = 8.92 +/- 0.1; Emax = 130 +/- 16%) than the rings from control patients (pD2 = 6.04 +/- 0.08; Emax = 56 +/- 8% for noradrenaline…