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Caval Vein (caval + vein)
Kinds of Caval Vein Selected AbstractsEffects of Corticosteroid Therapy on the Long-Term Outcome of Radiofrequency Lesions in the Swine Caval VeinsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2008GUILHERME FENELON M.D. Background: We explored the angiographic and pathological effects of corticosteroids on the long-term outcome of radiofrequency (RF) ablation lesions in the swine caval veins. Methods: Under fluoroscopy guidance, a single linear RF lesion (4-mm tip, 60°C, 180 seconds) was created in each vena cava (from ±2 cm into the vein to the venoatrial junction) of 20 anesthetized minipigs (35± 2 kg). Three groups were studied: acute (n = 4), killed 1 hour after RF; control (n = 8), sacrificed 83± 1 days after RF; and pigs (n = 8) receiving hydrocortisone (400 mg i.v. after RF) and prednisone (25 mg po for 30 days), killed 83± 1 days post-RF. Angiography was performed before, immediately after ablation, and at follow-up. Then, animals were sacrificed for histological analysis. Results: Mild (<40%) or moderate (41,70%) acute luminal narrowing occurred in 19/20 (95%) inferior veins and in 13/20 (65%) superior veins. Severe (>70%) stenosis and occlusions were not noted. At follow-up, in both chronic groups, mean vessel diameters returned to baseline and progression of luminal narrowing did not occur in any vein. Of note, superior and inferior vena cava angiographic diameter for control and treated pigs did not differ. The same was observed for the cross-sectional luminal area. Acute lesions displayed transmural coagulative necrosis whereas chronic lesions revealed marked fibrosis. Histological findings were similar in controls and treated pigs. Conclusion: In this model, mild and moderate stenosis, occurring immediately after ablation, seems to resolve over time. Corticosteroids do not affect the long-term outcome of such RF lesions in the caval veins. [source] Acute and Chronic Effects of Extensive Radiofrequency Lesions in the Canine Caval Veins: Implications for Ablation of Atrial ArrhythmiasPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006GUILHERME FENELON M.D. Background: Although radiofrequency (RF) ablation within the caval veins has been increasingly used to treat a variety of atrial tachyarrhythmias, the consequences of RF ablation in the caval veins are unknown. We explored the acute and chronic angiographic and pathological effects of extensive RF ablation in the caval veins. Methods: Under fluoroscopy guidance, conventional (4 mm tip, 60°C, 60 seconds) RF applications (n = 6,7) were delivered in each vena cava (from ±2 cm into the vein to the veno-atrial junction) of 15 dogs (10 ± 3 kg). Animals were killed 1 hour and 5 weeks after ablation for histological analysis. Angiography was performed before ablation (acute dogs only) and at sacrifice to assess the degree of vascular stenosis. Results: In acute dogs (n = 5), luminal narrowing was noted in 10/10 (100%) targeted veins (mild in two; moderate in three and severe in five, including two total occlusions). In the six chronic animals that completed the protocol (four died during follow-up), stenosis was also observed in 12/12 (100%) ablated veins (mild in six; moderate in four and severe in two). Of these, one superior vena cava was suboccluded with development of extensive collateral circulation. Histologically, acute lesions displayed typical transmural coagulative necrosis, whereas chronic lesions revealed intimal proliferation, necrotic muscle replaced with collagen, endovascular contraction, and disruption and thickening of the internal elastic lamina. Conclusion: In this model, extensive RF ablation in the caval veins may result in significant vascular stenosis. These findings may have implications for catheter ablation of arrhythmias originating within the caval veins. [source] Atrial Morphology in Hearts with Congenitally Corrected Transposition of the Great Arteries: Implications for the InterventionistJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2002RAJNISH JUNEJA M.D. Atrial Morphology in Congenitally Corrected Transposition.Introduction: In view of the possible need for septal puncture to ablate left-sided lesions and the occasional difficulty in coronary sinus (CS) cannulation, we investigated relevant anatomic features in the right atrium of hearts with congenitally corrected transposition of the great arteries (ccTGA). Methods and Results: Nine hearts with ccTGA and an intact atrial septum and eight weight-matched normal hearts were examined by studying the "septal" aspect of the right atrium with reference to the oval fossa (OF). The anterior margin was arbitrarily measured as the shortest distance from the OF to the superior mitral/tricuspid annulus. The posterior margin was measured from the OF to the posterior-most edge of the right atrial "septal" surface. The total "septal" surface width was measured at the middle of the OF. The stretched OF dimensions and CS isthmus length were noted. Mann-Whitney test was used to compare absolute and indexed dimensions, i.e.. normalized to total width. The posterior margin in hearts with ccTGA was shorter than in controls (6.3 ± 2.4 mm vs 11 ± 1.9 mm, P < 0.001; normalized margin P = 0.09). The CS isthmus also was significantly shorter (5.3 ± 2.7 mm vs 11.4 ± 2.2 mm, P < 0.001). In two hearts with ccTGA, the CS opening into the right atrium was on the same side of the eustachian valve as the inferior caval vein. Conclusion: The shorter posterior "septal" margin in hearts with ccTGA may increase the risk of exiting the heart while performing septal puncture when pointing the needle posteriorly. The shorter CS isthmus and the abnormal location of the CS opening in some of these hearts are important when contemplating radiofrequency ablation in this area. [source] Monitoring pulmonary perfusion by electrical impedance tomography: an evaluation in a pig modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009A. FAGERBERG Background: Electrical impedance tomography (EIT) is a non-invasive technique that generates images of impedance distribution. Changes in the pulmonary content of air and blood are major determinants of thoracic impedance. This study was designed to evaluate EIT in monitoring pulmonary perfusion in a wide range of cardiac output. Methods: Eight anaesthetised, mechanically ventilated pigs were fitted with a 16-electrode belt at the mid-thoracic level to generate EIT images that were analysed to determine pulse-synchronous systolic changes in impedance (,Zsys). Stroke volume (SV) was derived using a pulmonary artery catheter. Reductions in cardiac pre-load, and thus pulmonary perfusion, were induced either by inflating the balloon of a Fogarty catheter positioned in the inferior caval vein or by increasing the positive end-expiratory pressure (PEEP). All measurements were performed in a steady state during a short apnoea. Results: Pulse-synchronous changes in ,Zsys were easily discernable during apnoea. Balloon inflation reduced SV to 36% of the baseline, with a corresponding decrease in ,Zsys to 45% of baseline. PEEP reduced SV and ,Zsys to 52% and 44% of the baseline, respectively. Significant correlations between SV and ,Zsys were demonstrated during all measurements (,=0.62) as well as during balloon inflation (,=0.73) and increased PEEP (,=0.40). A Bland,Altman comparison of relative changes in SV and ,Zsys demonstrated a bias of ,7%, with 95% limits of agreement at ,51% and 36%. Conclusions: EIT provided beat-to-beat approximations of pulmonary perfusion that significantly correlated to a wide range of SV values achieved during both extra and intrapulmonary interventions to change cardiac output. [source] Effectiveness of porto-intracaval shunt to reduce the negative effects of portal and caval clamping in the rabbitMICROSURGERY, Issue 4 2001Gaetano La Greca M.D., Ph.D. In performing experimental liver surgery, it is difficult to prolong anhepatic time because the animals do not tolerate prolonged portal and caval clamping. To counteract prolonged venous stasis, the authors previously developed a simple porto-intracaval shunt. The shunt consists of a self-constructed inverted Y silicone tube. The effectiveness of this shunt was studied comparing two groups of 10 rabbits with shunt (S) versus those with clamped portal and inferior caval vein (C). In the group of rabbits that underwent porto-intracaval shunt, the results concerning intraoperative mortality, intraoperative increase in distal portal vein pressure, and incidence of the histologic signs of gut damage were clearly improved. The proposed porto-intracaval shunt was therefore effective in reducing some principal negative effects of portal and caval clamping. This type of porto-intracaval shunt can be therefore useful allowing improvement of experimental models concerning liver surgery in little animals. In chirurgia sperimentale del fegato è difficile prolungare il tempo anepatico dato che gli animali non tollerano un clampaggio portale e cavale prolungato. Gli Autori hanno precedentemente sviluppato un semplice shunt porto-intracavale con l'intento di ovviare alla stasi venosa prolungata. Lo shunt è costituito da un tubo di silicone a forma di Y invertita. Nel presente studio viene analizzata l'efficacia di questo shunt confrontando un gruppo di dieci conigli con shunt (S) rispetto al gruppo sottoposto invece al clampaggio della vena porta e della vena cava inferiore (C). I risultati riguardo mortalità intraoperatoria, incremento intraoperatorio della pressione portale distale e presenza e distribuzione di segni istologici di danno intestinale sono chiaramente migliori nel gruppo con shunt intra-porto cavale. Lo shunt porto-intracavale proposto è risultato realmente efficace nel ridurre alcuni dei principali effetti negativi del clampaggio portale e cavale. Questo tipo di shunt porto-intra cavale può essere quindi utile per migliorare le possibilità e i modelli di chirurgia sperimentale del fegato nei piccoli animali. © 2001 Wiley-Liss, Inc. MICROSURGERY 21:179,182 2001 [source] Comparison of different near-infrared spectroscopic cerebral oxygenation indices with central venous and jugular venous oxygenation saturation in childrenPEDIATRIC ANESTHESIA, Issue 2 2008NICOLE NAGDYMAN Summary Background:, We compared two different near-infrared spectrophotometers: cerebral tissue oxygenation index (TOI) measured by NIRO 200 and regional cerebral oxygenation index (rSO2) measured by INVOS 5100 with venous oxygen saturation in the jugular bulb (SjO2) and central SvO2 from the superior caval vein (SVC) during elective cardiac catheterization in children. Methods:, A prospective observational clinical study in 31 children with congenital heart defects in a catheterization laboratory was undertaken. TOI was compared with SjO2 in the left jugular bulb and with SvO2. rSO2 was compared with SjO2 from the right jugular bulb and SvO2. Linear regression analysis and Pearson's correlation coefficient were calculated and Bland,Altman analyses were performed. Results:, Cerebral TOI and SjO2 were significantly correlated (r = 0.56, P < 0.0001), as well as TOI and SvO2 with r = 0.74 (P < 0.0001). Bland,Altman plots showed a mean bias of ,4.3% with limits of agreement of 15.7% and ,24.3% for TOI and SjO2 and a mean bias of ,4.9% with limits of agreement of 10.3% and ,20.1% for TOI and SvO2. Cerebral rSO2 and SjO2 showed a significant correlation (r = 0.83, P < 0.0001) and rSO2 and SvO2 showed excellent correlation with r = 0.93 (P < 0.0001). Bland,Altman plots showed a mean bias of ,5.2% with limits of agreement of between 8.4% and ,18.8% for rSO2 and SjO2 and a mean bias of 5.6% with limits of agreement of 13.4% and ,2.2% for rSO2 and SvO2. Conclusions:, Both near-infrared spectroscopy devices demonstrate a significant correlation with SjO2 and SvO2 values; nevertheless both devices demonstrate a substantial bias of the measurements to both SjO2 and SvO2. [source] An In Vitro and In Vivo Study of the Detection and Reversal of Venous Collapse During Extracorporeal Life SupportARTIFICIAL ORGANS, Issue 2 2007Antoine P. Simons Abstract:, The objective of this study was to investigate venous collapse (VC) related to venous drainage during the use of an extracorporeal life support circuit. A mock circulation was built containing a centrifugal pump and a collapsible vena cava model to simulate VC under controlled conditions. Animal experiments were performed for in vivo verification. Changing pump speed had a different impact on flow during a collapsed and a distended caval vein in both models. Flow measurement in combination with pump speed interventions allows for the detection and quantitative assessment of the degree of VC. Additionally, it was verified that a quick reversal of a VC situation could be achieved by a two-step pump speed intervention, which also proved to be more effective than a straightforward decrease in pump speed. [source] Pulmonary arterial hypertension and right heart failure,A late-onset complication after cardiac catheterization,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2009Beate Koch MD Abstract Arteriovenous fistula is a possible complication of diagnostic procedures requiring arterial femoral catheterization. Late onset manifestation is reported rarely. An impressive case of severe pulmonary arterial hypertension and consecutive right heart failure caused by an arteriovenous fistula between the common iliac artery and the distal inferior caval vein manifesting four years after cardiac catheterization in described. © 2009 Wiley-Liss, Inc. [source] Persistence of Left Supracardinal Vein in an Adult Patient with Heart,Hand Syndrome and Cardiac PacemakerCONGENITAL HEART DISEASE, Issue 3 2008Jan Nemec MD ABSTRACT A patient with a sporadic heart,hand syndrome, which includes thumb hypoplasia, septum primum atrial septal defect, and cleft mitral valve is described. During attempted placement of a pacemaker lead, persistence of left superior and inferior vena cava was found in addition to the right-sided caval veins. This corresponds to persistence of left-sided supracardinal vein present during fetal development. [source] Effects of Corticosteroid Therapy on the Long-Term Outcome of Radiofrequency Lesions in the Swine Caval VeinsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2008GUILHERME FENELON M.D. Background: We explored the angiographic and pathological effects of corticosteroids on the long-term outcome of radiofrequency (RF) ablation lesions in the swine caval veins. Methods: Under fluoroscopy guidance, a single linear RF lesion (4-mm tip, 60°C, 180 seconds) was created in each vena cava (from ±2 cm into the vein to the venoatrial junction) of 20 anesthetized minipigs (35± 2 kg). Three groups were studied: acute (n = 4), killed 1 hour after RF; control (n = 8), sacrificed 83± 1 days after RF; and pigs (n = 8) receiving hydrocortisone (400 mg i.v. after RF) and prednisone (25 mg po for 30 days), killed 83± 1 days post-RF. Angiography was performed before, immediately after ablation, and at follow-up. Then, animals were sacrificed for histological analysis. Results: Mild (<40%) or moderate (41,70%) acute luminal narrowing occurred in 19/20 (95%) inferior veins and in 13/20 (65%) superior veins. Severe (>70%) stenosis and occlusions were not noted. At follow-up, in both chronic groups, mean vessel diameters returned to baseline and progression of luminal narrowing did not occur in any vein. Of note, superior and inferior vena cava angiographic diameter for control and treated pigs did not differ. The same was observed for the cross-sectional luminal area. Acute lesions displayed transmural coagulative necrosis whereas chronic lesions revealed marked fibrosis. Histological findings were similar in controls and treated pigs. Conclusion: In this model, mild and moderate stenosis, occurring immediately after ablation, seems to resolve over time. Corticosteroids do not affect the long-term outcome of such RF lesions in the caval veins. [source] Acute and Chronic Effects of Extensive Radiofrequency Lesions in the Canine Caval Veins: Implications for Ablation of Atrial ArrhythmiasPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006GUILHERME FENELON M.D. Background: Although radiofrequency (RF) ablation within the caval veins has been increasingly used to treat a variety of atrial tachyarrhythmias, the consequences of RF ablation in the caval veins are unknown. We explored the acute and chronic angiographic and pathological effects of extensive RF ablation in the caval veins. Methods: Under fluoroscopy guidance, conventional (4 mm tip, 60°C, 60 seconds) RF applications (n = 6,7) were delivered in each vena cava (from ±2 cm into the vein to the veno-atrial junction) of 15 dogs (10 ± 3 kg). Animals were killed 1 hour and 5 weeks after ablation for histological analysis. Angiography was performed before ablation (acute dogs only) and at sacrifice to assess the degree of vascular stenosis. Results: In acute dogs (n = 5), luminal narrowing was noted in 10/10 (100%) targeted veins (mild in two; moderate in three and severe in five, including two total occlusions). In the six chronic animals that completed the protocol (four died during follow-up), stenosis was also observed in 12/12 (100%) ablated veins (mild in six; moderate in four and severe in two). Of these, one superior vena cava was suboccluded with development of extensive collateral circulation. Histologically, acute lesions displayed typical transmural coagulative necrosis, whereas chronic lesions revealed intimal proliferation, necrotic muscle replaced with collagen, endovascular contraction, and disruption and thickening of the internal elastic lamina. Conclusion: In this model, extensive RF ablation in the caval veins may result in significant vascular stenosis. These findings may have implications for catheter ablation of arrhythmias originating within the caval veins. [source] | ||||||||||||||||||||||