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At least 721 records · Page 40Linked to original sources
PubMed1997

[Surgical repair of varicose veins of the lower limbs by saphenous vein stripping].

For a long time, high ligation and stripping of the saphenous trunk was the only technique used to deal with primary varicose veins when surgical treatment was recommended. Duplex ultrasound has demonstrated that this attitude is not well-founded in many cases. Alternative techniques have been proposed and performed. Some of them have not been submitted to randomised and prospective studies. Others, particularly high ligation and stab avulsion of collaterals with preservation of the long saphenous trunk, have been evaluated. The author indicates in which cases high ligation + stripping of the saphenous trunk remains justified and in which situations it is not. All indications must be based on clinical examination and duplex ultrasound.

Humans↗
PubMed2001

Rat auxiliary liver transplantation without portal vein reconstruction: comparison with the portal vein-arterialized model.

Auxiliary liver transplantation (ALT) has been reintroduced in clinical cases recently and is now believed to be a viable alternative to orthotopic liver transplantation. To provide a simple rat ALT model for studying the physiological and immunological aspects of the ALT graft, a new ALT was performed, and the comparison between this new model and the portal arterialized one that was reported by other investigators was carried out. At first, we confirmed that liver could tolerate the deprivation of its portal flow well, using a portosystemic shunted rat model. The new rat ALT model, in which the ALT graft obtained its blood inflow only from the hepatic artery, was then performed. Our results demonstrated that 50% of the hepatic artery-alone ALT graft showed almost normal structure histologically at 1 month after grafting, with bile secretion preserved. By contrast, only 8% 1-month graft survival was noted in the portal arterialized group, and all grafts stopped bile secretion 1 week after operation. In conclusion, with arterial blood supply alone, the ALT graft survived and demonstrated normal bile secretion function for more than 1 month. Portal vein arterialization is not an appropriate way to establish the graft's blood supply if no pressure adjustment measures were taken in advance.

Animals↗
PubMed1992

5-Hydroxytryptamine-induced contractions of the human isolated saphenous vein: involvement of 5-HT2 and 5-HT1D-like receptors, and a comparison with grafted veins.

The receptors mediating the contractile effect of 5-hydroxytryptamine (5-HT) on the human isolated saphenous vein, obtained from 42 patients undergoing coronary bypass surgery, have been further characterized using a number of 5-HT-related drugs. The rank order of agonist potency was 5-carboxamidotryptamine (5-CT) approximately 5-HT greater than methysergide approximately sumatriptan approximately alpha-methyl-5-HT approximately 5-methoxy-3-(1,2,3,6-tetrahydropyridin-4-yl)-1H-indolesuccinate (RU 24969) approximately 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI) greater than 2-methyl-5-HT greater than 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT). Flesinoxan was inactive as an agonist. Ketanserin (1 mumol/l) hardly affected sumatriptan-induced contractions but it caused a rightward shift of the upper part of the concentration-response curve of 5-HT and 5-CT. The same concentration of ketanserin caused a parallel rightward shift of the concentration-response curves of alpha-methyl-5-HT and DOI with pKB values of 7.1 and 7.1, respectively. The responses to sumatriptan were antagonized by methiothepin (0.1 mumol/l), metergoline (0.1 and 1 mumol/l), rauwolscine (1 mumol/l) and cyanopindolol (1 mumol/l); the calculated pKB values were 7.3, 6.9, 7.3, 6.7 and 6.5, respectively. Contractions to 5-HT were antagonized by methysergide (1 mumol/l), methiothepin (0.1 mumol/l; pKB = 7.1), ICS 205-930 (1 mumol/l; pKB = 5.9) and flesinoxan (30 mumol/l; pKB = 5.3). Remarkably, the contractions elicited by 2-methyl-5-HT were not attenuated by ICS 205-930, but were antagonized by methiothepin (0.1 mumol/l) and, more markedly, by ketanserin (1 mumol/l).(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Artery Bypass↗
PubMed2005

Prothrombin G20210A gene variant is not associated with idiopathic portal vein thrombosis in an area endemic for portal vein thrombosis.

Prothrombin G20210A gene variant has been found in 0-23% of patients with portal vein thrombosis (PVT). This wide variation makes it difficult to assess the importance of prothrombin G20210A gene variant as a predisposing factor for PVT. In this study from South India, none of the patients with idiopathic PVT (0/38) or any of the controls (0/46) had prothrombin G20210A gene variant. Prothrombin G20210A gene variant does not contribute to the development of PVT in India.

Adolescent↗
PubMed2006

Hepatic effects of influxed endothelin-1 from portal vein: in situ portal vein infusion model using dogs.

BACKGROUND/PURPOSE: Endothelin-1 is a potent vasoconstrictor formed by vascular endothelium. This study was designed to investigate the hepatic effect of endothelin-1 produced by portal vascular endothelium. METHODS: Portal venous pressure, portal venous flow, hepatic arterial flow, tissue blood flow, and tissue oxygen pressure were measured during portal vein endothelin-1 infusion in dogs at rates of 1.0 to 5.0 ng/kg per minute. Sinusoidal width during maximal infusion was determined morphometrically. Serum concentrations of mitochondrial glutamic oxaloacetic transaminase and endothelin-1 in portal and hepatic venous blood were also measured. RESULTS: Intraportal endothelin-1 infusion dose-dependently increased portal venous pressure and reduced portal venous and hepatic arterial blood flow. Tissue blood flow and oxygen pressure also decreased. Endothelin-1 also significantly increased serum mitochondrial glutamic oxaloacetic transaminase and constricted hepatic sinusoids. These changes reversed after completion of infusion. CONCLUSIONS: Intraportal endothelin-1 caused circulatory and histological changes in hepatic sinusoids that may suggest the role of endothelin-1 formed by portal venous bed epithelium.

Animals↗
PubMed2006

Pulmonary vein isolation under direct visual identification of the left atrium-pulmonary vein junction using intra-cardiac echography.

INTRODUCTION: Intra-cardiac echocardiography (ICE) which has some benefits, can be used to obtain detailed anatomy of the heart chambers or large vessels, and the catheter positions, and it has been considered useful for improving the outcome of the ablation. In the present study, we performed pulmonary vein isolation (PVI) under real time monitoring of ICE imaging utilizing an ICE catheter placed at the junction of the left atrium (LA) and PVs (LA-PV junction). METHODS: PVI for atrial fibrillation (AF) was performed in 30 cases with drug-resistant AF (mean age: 66-years-old; including 22 males). An ICE catheter utilizing a 9 MHz frequency was inserted into the LA via the atrial septum, and placed at the LA-PV junction. Circumferential ablation was performed in the LA outside of the PV ostium, encircling both the superior and inferior ostia together under ICE imaging. RESULTS: The anatomy of the LA to the PVs and catheter sites were clearly identified by the ICE during the procedure, which enabled a precise and safe catheter manipulation with minimal fluoroscopy. Further, the wall thickness of the PV and LA, and position of the esophagus could be obtained by ICE, facilitating care in adjusting the power and/or duration of the current delivery. CONCLUSION: ICE imaging of the LA-PV junction permitted real time monitoring of the target sites for PVI during the ablation procedure, and was considered a useful technique for performing PVI.

Aged↗
PubMed2006

Recurrence of pulmonary vein conduction and atrial fibrillation after pulmonary vein isolation for atrial fibrillation: a randomized trial of the ostial versus the extraostial ablation strategy.

BACKGROUND: Both segmental ostial and circumferential extraostial pulmonary vein (PV) isolation have been proven effective in the treatment of atrial fibrillation (AF). However, the recurrence of AF and PV conduction after the 2 ablation strategies has never been compared in a randomized study. METHODS: A total of 100 consecutive patients (age 56 +/- 10; 71 men) with symptomatic AF (paroxysmal, 51; persistent, 49) were randomized to segmental ostial (n = 54) or circumferential extraostial (n = 46) PV isolation. A circular catheter positioned at the ostium of each target PV guided the ostial PV isolation. Extraostial PV isolation was performed by encircling the paired left and right PVs, respectively, guided by an electroanatomic mapping system. RESULTS: A total of 84% of the patients had recurrent AF after the first PV isolation procedure, showing 72% with AF and 12% with organized left atrial tachycardia. In patients undergoing reablation, all but 2 patients had recurrence of left atrium PV conduction (>95%). During a mean follow-up of 12 months without antiarrhythmic medication, 57% of patients who underwent extraostial PV isolation were free of arrhythmia symptoms compared with 31% of patients who underwent ostial PV isolation (P < .05). This difference in success rate between the 2 ablation strategies was mainly seen in patients known with persistent AF (52% and 15%, respectively; P = .02) as opposed to patients with paroxysmal AF (65% and 46%, respectively; P = .26). CONCLUSIONS: Overall, the more proximal, extraostial PV isolation was found to be superior to ostial PV isolation, especially in patients known with persistent AF. A high recurrence rate of 84% after a single complete PV isolation procedure was seen. At reablation, more than 95% had recurrence of left atrium PV conduction regardless of the procedure used, supporting the idea that complete PV isolation seems essential to prevent arrhythmia recurrences.

Aged↗
PubMed2005

Errors in pulmonary vein identification and ostia location in the absence of pulmonary vein imaging.

BACKGROUND: A key point in atrial fibrillation (AF) ablation is the ability to identify the pulmonary vein (PVs) and locate their ostia. OBJECTIVES: The purpose of this study was to assess the error margin of PV identification and ostia location in the absence of previous PV imaging. METHODS: This study was performed in patients referred for catheter ablation of AF. PVs were reconstructed before ablation using the CARTO system. The operator tagged the superior and inferior edges of the PV ostia before and after examining the corresponding PV angiograms. The distances between the tagged PV ostia were measured using CARTO software. RESULTS: A total of 105 location estimations of 54 PVs were analyzed. The location of PV ostia without angiography deviated from the angiographic PV ostia by a median of 13 mm (95% confidence interval = 11-14 mm; P < .0001). In 84 of the 105 estimations (80%), wrong tagging was performed inside the PV. A multiple logistic regression revealed that, at sites displaying PV potentials, the left atrial potential amplitude was an independent predictor of location at the angiographic PV ostium (odds ratio 24 [95% confidence interval = 3.7-227] per 1-mV increase). Receiver operator characteristic analysis set the optimal cutoff level at 0.7 mV. Use of this criterion improved the accuracy of PV ostium location by 4 mm (95% confidence interval = 1-6 mm; P = .005). CONCLUSION: Attempts at PV identification and ostia location in the absence of previous PV imaging are subject to a broad error margin.

Adult↗
PubMed2006

Predictors of success after selective pulmonary vein isolation of arrhythmogenic pulmonary veins for treatment of atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) ablation procedures typically involve isolation of all pulmonary veins (PVs) in addition to adjunctive linear lesions, yet the need for such an extensive ablation strategy in all patients is unclear. OBJECTIVES: The purpose of this study was to identify a subgroup of patients undergoing AF ablation with good clinical success after limited PV isolation. METHODS: Patients (N = 450) underwent trigger-guided segmental isolation of only arrhythmogenic PVs. We compared clinical characteristics of patients who required isolation of only one or two PVs to those in whom AF ablation required isolating > or = 3 PVs. RESULTS: For the group of patients undergoing isolation of < or = 2 PVs, AF freedom without antiarrhythmic drug use was achieved in 56 (58%) of 97 patients, and AF control was achieved in 66 (68%) of 97 patients after a single procedure. After additional procedures, 77 (79%) of 97 patients achieved complete AF freedom without antiarrhythmic drugs, and 82 (85%) of 97 patients achieved AF control. Younger age (odds ratio [OR] 1.05; confidence interval [CI] 1.01,1.09) and lack of persistent AF (OR 3.27; CI 1.0, 10.7) were each independent predictors of freedom from AF. In patients younger than 50 years with paroxysmal AF undergoing isolation of < or = 2 PVs (n = 44), AF freedom without antiarrhythmic drugs was achieved in 32 (73%) of 44 after a single ablation procedure. CONCLUSION: Targeted PV isolation has a good long-term (18-month) success rate in patients younger than 50 years with paroxysmal AF and < or = 2 PVs triggering AF.

Atrial Fibrillation↗
PubMed2006

Electrophysiological pulmonary vein antrum isolation with a multielectrode basket catheter is feasible and effective for curing paroxysmal atrial fibrillation: efficacy of minimally extensive pulmonary vein isolation.

BACKGROUND: How extensive should an appropriate pulmonary vein (PV) ablation be is a matter of controversy. OBJECTIVE: The study's aim was to investigate the efficacy of minimally extensive PV ablation for isolating the PV antrum (PVA) with the guidance of electrophysiological parameters. METHODS: Fifty-five consecutive symptomatic paroxysmal atrial fibrillation (PAF) patients underwent PV mapping with a multielectrode basket catheter (MBC). A 31-mm MBC was deployed in 3-4 PVs as proximally as possible without dislodgement, and the longitudinal PV mapping enabled us to recognize single sharp potentials formed by the total fusion of the PV and left atrial potentials around the PV ostium or the transverse activation patterns that were observed. Those potentials were defined as PVA potentials. Radiofrequency ablation was performed circumferentially targeting PVA potentials with the end point being their elimination. RESULTS: After circumferential PVA ablation, electrical disconnection was achieved in 77% and residual PVA conduction gaps were observed in 23% of all targeted PVs. Those residual conduction gaps were mainly located at the border between ipsilateral PVs (42%) and between the left PVs and left atrial appendage (33%) and were eliminated by a mean of 3 +/- 2 minutes of local radiofrequency deliveries. During the follow-up period (11 +/- 5 months), 46 (84%) patients were free of symptomatic PAF without any anti-arrhythmic drugs. No PV stenosis or spontaneous left atrial flutter occurred. CONCLUSIONS: Electrophysiological PVA ablation with an MBC is feasible and effective for curing PAF because this minimally extensive PVA isolation technique targets the optimal sites, achieving both high efficacy and safety.

Aged↗
PubMed1997

Late myocardial ischemic events after saphenous vein graft intervention--importance of initially "nonsignificant" vein graft lesions.

Patients undergoing percutaneous coronary revascularization (PCR) for narrowed saphenous vein grafts (SVGs) have a high incidence of subsequent cardiac events, but the relative contribution of treated and untreated SVGs, and of native coronary narrowings to late events is uncertain. This study evaluated the role of progression of SVG disease at untreated sites to cardiac events in these patients. All patients with successful PCR of SVG lesions who were enrolled in clinical trials with mandated repeat angiography from 1990 to 1994 were studied. One hundred three patients (age 63 +/- 8 years, 82% men, ejection fraction 54 +/- 12%, graft age 8 +/- 4 years), contributing 1,095 analyzable 15- to 25-mm SVG segments were followed 29 +/- 13 months (4 patients were lost to follow-up). Actuarial event-free (death, myocardial infarction, bypass surgery, or PCR) and overall survival at 12 months were 47 +/- 5% and 94 +/- 2%, respectively. Fifty-six percent of all early (< or = 12 months) events resulted from ischemia from recurrence at initially treated SVG sites, 26% at nontreated SVG sites, and 14% at nontreated native coronary sites. By 36 months, event-free and overall survival were 25 +/- 6% and 86 +/- 4%, respectively. Events occurring > 12 months after initial treatment resulted most frequently from ischemia from progression of narrowing at untreated SVG sites (46%). Ischemic events from initially untreated SVG sites were correlated with initial percent stenosis (initial, 41% to 50%; 45% events, 31% to 40%; 18% events, < or = 30%; 2% events, p <0.001) and reference SVG diameter (p = 0.003). Recurrent ischemic events from initially treated SVG sites were independently correlated with initial percent stenosis (initial > 75%; 43% events, 50% to 75%; 27% events, < 50%; 18% events, p = 0.01), but not with final percent stenosis. The frequent occurrence of events from nontreated 41% to 50% stenoses suggests a need for increased surveillance in patients with these lesions. The low incidence of events from initially treated lesions < 50% suggests that the hypothesis that "nonsignificant" 41% to 50% lesions might best be treated at the time other more severe narrowings are treated should be examined.

Aged↗
PubMed2003

Natural history of inadvertent aorta-saphenous vein-coronary vein bypass graft.

Inadvertent distal anastomosis of an aortocoronary bypass graft to a coronary vein is a rare but potentially serious complication of coronary artery bypass surgery. We describe a patient in whom such a conduit was discovered only incidentally 17 years after its creation. This case illustrates the pertinent features of this anomaly and demonstrates that it can have a benign natural history.

Aged↗
PubMed1980

Ureteral and renal vein perforation with placement into the renal vein as a complication of the pigtail ureteral stent.

A 43-year-old woman with recurrent colon carcinoma presented with bilateral pelvioureteral obstruction. After a 6F ureteral catheter had been in place for 4 days the left ureter was perforated near the ureteropelvic junction, while an attempt was made to insert a 7F Cook indwelling pigtail ureteral stent. The errant stent was allowed to remain in its extraureteral locale until urinary drainage was established. To our surprise the stent had been placed into the renal vein, after exiting the ureter 2 cm. inferiorly. There was excellent tamponade. When the large stent was removed severe bleeding ensued that was controlled by ligatures. Methods to prevent perforation are discussed. Should perforation of these stents occur in the proximal ureter or renal pelvis it would seem judicious to leave these in place rather than perform any further endoscopic manipulation before surgical inspection.

Adult↗
PubMed2003

Pulmonary vein isolation using transvenous catheter cryoablation for treatment of atrial fibrillation without risk of pulmonary vein stenosis.

OBJECTIVES: We sought to evaluate the efficacy and safety of pulmonary vein (PV) isolation using transvenous cryoablation for the treatment of atrial fibrillation (AF). BACKGROUND: Although electrical isolation of PVs with radiofrequency energy for the treatment of AF is feasible, it is associated with a significant risk of PV stenosis. Cryoablation is a new alternative therapy allowing ablation of tissue while preserving its underlying architecture. METHODS: In 52 patients with paroxysmal (n = 45) or persistent (n = 7) AF, PV isolation using the CryoCor cryoablation system (CyroCor Inc., San Diego, California) with a 10F deflectable transvenous catheter was performed as guided by ostial PV potentials. Cryoablation was applied twice at each targeted site (2.5 to 5 min/application). Computed tomography (CT) of the thorax was performed at baseline and at 3 and 12 months to evaluate for PV stenosis. RESULTS: All targeted PVs were completely isolated in 49 (94%) of 52 of patients. Of 152 PVs targeted, 147 (97%) were successfully isolated (mean 3.0 PVs isolated per patient). After a mean period of 12.4 +/- 5.5 months of follow-up, 37 (71%) of 52 patients had no recurrence of AF or were clinically improved, including 29 patients (56%) who had no recurrence of AF with (n = 11) or without the use of anti-arrhythmic drugs. At 3 and 12 months, the CT scan showed no evidence of PV stenosis associated with cryoablation in any patients. CONCLUSIONS: Transvenous catheter cryoablation is an effective method to create PV electrical isolation for the treatment of AF. A clinically satisfactory result can be achieved in 71% of patients with AF, without the risk of PV stenosis.

Adult↗