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Vena Cava (vena + cava)
Kinds of Vena Cava Terms modified by Vena Cava Selected AbstractsPersistent Left-Sided Superior Vena Cava: Integrated Noninvasive DiagnosisECHOCARDIOGRAPHY, Issue 9 2007Antonino Recupero M.D. Persistent left superior vena cava (PLSVC) is a rare finding. We describe 5 patients with PLSVC diagnosed by a noninvasive approach, including two-dimensional (2D) echocardiogram, nuclear magnetic resonance and multislice computed tomography (MCT). In 4 cases the PLSVC was isolated ("alone PLSVC"), and in 1 case associated with a right superior vena cava. [source] Drainage of the Inferior Vena Cava to the Left AtriumECHOCARDIOGRAPHY, Issue 2 2003Haran Burri M.D. Drainage of the inferior vena cava to the left atrium is an extremely unusual congenital heart disease. We describe a 54-year-old woman, in whom the diagnosis was suggested by transthoracic echocardiography, and then confirmed by a transesophageal exam and magnetic resonance imaging, which also revealed an associated secundum atrial septal defect. Surgical management involved reconstruction of the interatrial septum to include the inferior vena cava in the right atrium. The few previously reported cases in the literature are reviewed. (ECHOCARDIOGRAPHY, Volume 20, February 2003) [source] Successful Surgical Correction of a Single Atrium Associated with Cleft Mitral Valve Persistent Left Superior Vena Cava and Pulmonary Valvular Stenosis as an Isolated Cardiac DefectJOURNAL OF CARDIAC SURGERY, Issue 3 2005Akin Izgi M.D. It is extremely rare for SA to be observed as an isolated defect. We report here a 13-year-old male patient with SA as an isolated cardiac defect, successfully corrected by surgery. [source] Impact of Systematic Isolation of Superior Vena Cava in Addition to Pulmonary Vein Antrum Isolation on the Outcome of Paroxysmal, Persistent, and Permanent Atrial Fibrillation Ablation: Results from a Randomized StudyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2010ANDREA CORRADO M.D. Impact of the Systematic Isolation of the Superior Vena Cava.,Background: Pulmonary veins (PVs) have been shown to represent the most frequent sites of ectopic beats initiating paroxysmal atrial fibrillation (AF). However, additional non-PV triggers, arising from different areas, have been reported as well. One of the most common non-PV sites described is the superior vena cava. Aims: The purpose of the study was to investigate the impact resulting from the systematic isolation of the superior vena cava (SVCI) in addition to pulmonary vein antrum isolation (PVAI) on the outcome of paroxysmal, persistent, and permanent AF ablation. Methods: A total of 320 consecutive patients who had been referred to our center in order to undergo a first attempt of AF ablation were randomized into 2 groups. Group I (160 patients) underwent PVAI only; Group II (160 patients) underwent PVAI and SVCI. Results: AF was paroxysmal in 134 (46%), persistent in 75 (23%), and permanent in 111 (31%) of said patients. SVCI was performed on 134 of the 160 patients (84%) in Group II. SVC isolation was not performed on the remaining 26 patients either because of phrenic nerve capture or the lack of SVC potentials. Comparison of the outcome data between the 2 groups, after a follow-up of 12 months, revealed a significant difference in total procedural success solely with patients manifesting paroxysmal atrial fibrillation (56/73 [77%] Group I vs. 55/61 [90%] Group II; P = 0.04; OR 2.78). Conclusions: In our study, the strategy of the empiric SVCI in addition to PVAI has improved the outcome of AF ablation solely in patients manifesting paroxysmal AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1,5, January 2010) [source] Usefulness of Interatrial Conduction Time to Distinguish Between Focal Atrial Tachyarrhythmias Originating from the Superior Vena Cava and the Right Superior Pulmonary VeinJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2008KUAN-CHENG CHANG M.D. Objective: Differentiation of the tachycardia originating from the superior vena cava (SVC) or the right superior pulmonary vein (RSPV) is limited by the similar surface P-wave morphology and intraatrial activation pattern during tachycardia. We sought to find a simple method to distinguish between the two tachycardias by analyzing the interatrial conduction time. Methods: Sixteen consecutive patients consisting of 8 with SVC tachycardia and the other 8 with RSPV tachycardia were studied. The interatrial conduction time from the high right atrium (HRA) to the distal coronary sinus (DCS) and the intraatrial conduction time from the HRA to the atrial electrogram at the His bundle region (HIS) were measured during the sinus beat (SR) and during the tachycardia-triggering ectopic atrial premature beat (APB). The differences of interatrial (,[HRA-DCS]SR-APB) and intraatrial (,[HRA-HIS]SR-APB) conduction time between SR and APB were then obtained. Results: The mean ,[HRA-DCS]SR-APB was 1.0 ± 5.2 ms (95% confident interval [CI],3.3,5.3 ms) in SVC tachycardia and 38.5 ± 8.8 ms (95% CI 31.1,45.9 ms) in RSPV tachycardia. The mean ,[HRA-HIS]SR-APB was 1.5 ± 5.3 ms (95% CI ,2.9,5.9 ms) in SVC tachycardia and 19.9 ± 12.0 ms (95% CI 9.9,29.9 ms) in RSPV tachycardia. The difference of ,[HRA-DCS]SR-APB between SVC and RSPV tachycardias was wider than that of ,[HRA-HIS]SR-APB (37.5 ± 9.3 ms vs. 18.4 ± 15.4 ms, P < 0.01). Conclusions: The wide difference of the interatrial conduction time ,[HRA-DCS]SR-APB between SVC and RSPV tachycardias is a useful parameter to distinguish the two tachycardias and may avoid unnecessary atrial transseptal puncture. [source] Electrical Disconnection of the Superior Vena Cava from the Right AtriumJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2004VINOD K. JAYAM M.D. [source] High-Resolution Mapping of Tachycardia Originating from the Superior Vena Cava: Evidence of Electrical Heterogeneity, Slow Conduction, and Possible Circus Movement ReentryJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2002DIPEN C. SHAH M.D. Superior Vena Cava Reentry. High-resolution mapping of a tachycardia originating from the superior vena cava (SVC) in a patient with atrial fibrillation is described. Unidirectional circuitous repetitive activation encompassing the full tachycardia cycle length was documented around a line of block within the myocardial sleeve of the SVC. Intermittent conduction to the right atrium resulted in an irregular atrial tachycardia. Evidence of electrical heterogeneity and slow conduction persisted in sinus rhythm and was exaggerated by premature stimulation but did not reproduce the activation pattern during tachycardia. All the available evidence is best compatible with circus movement reentry within the SVC, with marked slow and anisotropic conduction responsible for the restricted dimensions of the reentrant circuit. These findings may suggest a similar substrate and arrhythmia mechanism in the myocardium of the pulmonary veins. [source] Transvenous Parasympathetic Nerve Stimulation in the Inferior Vena Cava and Atrioventricular ConductionJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2000PATRICK SCHAUERTE M.D. Parasympathetic Stimulation in the Inferior Vena Cava. Introduction: In previous reports, we demonstrated a technique for parasympathetic nerve stimulation (PNS) within the superior vena cava, pulmonary artery, and coronary sinus to control rapid ventricular rates during atrial fibrillation (AF). In this report, we describe another vascular site, the inferior vena cava (IVC), at which negative dromotropic effects during AF could consistently he obtained. Moreover, stimulation at this site also induced dual AV nodal electrophysiology. Methods and Results: PNS was performed in ten dogs using rectangular stimuli (0.1 msec/20 Hz) delivered through a catheter with an expandable electrode basket at its tip. Within 3 minutes and without using fluoroscopy, the catheter was positioned at an effective PNS site in the IVC at the junction of the right atrium. AF was induced and maintained by rapid atrial pacing. During stepwise increase of the PNS voltage from 2 to 34 V, a graded response of ventricular rate slowing during AF was observed (266 ± 79 msec without PNS vs 1,539 ± 2,460 msec with PNS at 34 V; P = 0.005 by analysis of variance), which was abolished by atropine and blunted by hexamethonium. In three animals, PNS was performed during sinus rhythm. Dual AV nodal electrophysiology was present in 1 of 3 dogs in control, whereas with PNS, dual AV nodal electrophysiology was observed in all three dogs. PNS did not significantly change sinus rate or arterial blood pressure during ventricular pacing. Conclusion: Stable and consistent transvenous electrical stimulation of parasympathetic nerves innervating the AV node can be achieved in the IVC, a transvenous site that is rapidly and readily accessible. The proposed catheter approach for PNS can be used to control ventricular rate during AF in this animal model. [source] Focal Atrial Tachycardia Originating from the Donor Superior Vena Cava after Bicaval Orthotopic Heart TransplantationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2010HAW-KWEI HWANG M.D. An 11-year-old boy, who underwent bicaval orthotopic heart transplantation for idiopathic dilated cardiomyopathy, had a focal atrial tachycardia originating from the donor superior vena cava. The pathogenesis of this tachycardia may be related to transplant rejection or transplant vasculopathy. Radiofrequency catheter ablation can eliminate this unique tachycardia and result in hemodynamic improvement. (PACE 2010; e68,e71) [source] Atrioventricular Nodal Tachycardia in a Patient with Anomalous Inferior Vena Cava with Azygos Continuation and Persistent Left Superior Vena CavaPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2009MIGUEL A. ARIAS M.D., Ph.D. A 39-year-old female patient was referred for ablation of recurrent episodes of atrioventricular nodal reentrant tachycardia. A combination of an anomalous inferior vena cava with azygos continuation and a persistent left superior vena cava was discovered. A nonfluoroscopic navigation system was very useful for catheter ablation of the tachycardia in this unusual case of anomalous venous system of the heart. [source] Implant of a Biventricular Pacemaker in a Patient with Dextrocardia and Persistent Left Superior Vena CavaPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2006CHRISTIAN POTT Congenital anomalies of the heart can pose challenges to cardiac invasive procedures. Here, we present the case of a 40-year-old man with the combination of dextrocardia, a persistent left superior vena cava, and idiopathic dilated cardiomyopathy. We describe the successful implantation of a biventricular pacemaker,defibrillator under this complex anatomic condition. [source] Pathological Findings of the Isthmus Between the Inferior Vena Cava and Tricuspid Annulus Ablated by Radiofrequency ApplicationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2000ISAO KOHNO Anatomically guided radiofrequency ablation for the treatment of atrial flutter was performed in a 41-year-old man with interstitial pneumonia. He died of respiratory failure 2 months after ablation, and an autopsy was performed. The whole layer of the ablation site showed a transluminal fibrosis. [source] Origin of the Infrarenal Part of the Caudal Vena cava in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2008P. Cornillie Summary The vascular topography in the lumbar region of pig embryos and young fetuses was three-dimensionally reconstructed to study some controversial aspects of the origin and development of the infrarenal part of the caudal vena cava. Contrary to general belief, it was found that the supracardinal veins, which form the azygos veins in the thorax, do not take part in the construction of the caudal vena cava in the lumbar region. These veins do appear in the abdomen, but they are only involved in the formation of the lumbar and ascending lumbar veins. The infrarenal part of the caudal vena cava arises from the lumbar part of the right caudal cardinal vein. Whilst this venous pattern is established, the lumbar part of the left caudal cardinal vein disappears and its former location is occupied by large lymphatic connections between the cysterna chyli and the retroperitoneal mesenteric lymphatic sac. On the basis of these findings, a number of hypotheses on the development of anatomical variations of the caudal vena cava should be reconsidered. [source] Anomalous Left Anterior Descending Coronary Artery from the Pulmonary Artery, Unroofed Coronary Sinus, Patent Foramen Ovale, and a Persistent Left-sided SVC in a Single Patient: A Harmonious Quartet of DefectsCONGENITAL HEART DISEASE, Issue 2 2009Andrew J. Klein MD ABSTRACT Unroofing of the coronary sinus without complex structural heart defects is a rare congenital defect often seen in conjunction with a persistent left-sided superior vena cava. Anomalous origin of the left anterior descending artery from the pulmonary artery with normal origin of the left circumflex coronary artery is an even rarer congenital cardiac defect. We report a case of a 54-year-old woman presenting with mild dyspnea on exertion who was found on invasive and noninvasive evaluations to have a unique combination of defects,unroofed coronary sinus, persistent left-sided superior vena cava, patent foramen ovale, and anomalous origin of the left anterior descending artery from the pulmonary artery without evidence of previous coronary ischemia. [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] Hemiazygos Venous Additional Pulmonary Flow for Successful Total Cavo-pulmonary ConnectionCONGENITAL HEART DISEASE, Issue 5 2007Koichi Sughimoto MD ABSTRACT Patients who underwent only Glenn procedure after being deemed unsuitable candidates for Fontan completion are not small in number, and may develop arterio-venous (AV) pulmonary malformations during the follow-up period. We present the case of a 17-year-old woman with severe systemic desaturation 13 years after Glenn procedure and repair of total anomalous pulmonary venous return. Among other anomalies, the patient disclosed hemiazygos continuation to a persistent left superior vena cava. This case supports the concept that returning flow from the abdominal vein plays an important role in the well-balanced growth of the pulmonary artery and in the inhibition of the pulmonary AV malformation. [source] Neonatal Congestive Heart Failure Due to a Subclavian Artery to Subclavian Vein Fistula Diagnosed by Noninvasive ProceduresCONGENITAL HEART DISEASE, Issue 3 2006Gregory H. Tatum MD ABSTRACT Congestive heart failure in the neonate is usually due to intracardiac anomalies or cardiac dysfunction. Extracardiac causes are rare. Patient., We report a newborn infant who presented with respiratory distress and cardiomegaly. Result., Echocardiography identified a dilated right subclavian artery and vein and superior vena cava. Magnetic resonance imaging confirmed a subclavian artery to subclavian vein fistula that was treated with surgical ligation. The infant recovered fully. This case underscores the need for clinical suspicion of fistulous connection in unusual locations in the face of unexplained heart failure in the neonate. Conclusion., Echocardiographic and magnetic resonance imaging are effective noninvasive modalities to confirm the diagnosis prior to surgical intervention. [source] Left ventricular mechanical dyssynchrony is load independent at rest and during endotoxaemia in a porcine modelACTA PHYSIOLOGICA, Issue 4 2009R. A'roch Abstract Aim:, In diseased or injured states, the left ventricle displays higher degrees of mechanical dyssynchrony. We aimed at assessing mechanical dyssynchrony ranges in health related to variation in load as well as during acute endotoxin-induced ventricular injury. Methods:, In 16 juvenile anaesthetized pigs, a five-segment conductance catheter was placed in the left ventricle as well as a balloon-tipped catheter in the inferior vena cava. Mechanical dyssynchrony during systole, including dyssynchrony time in per cent during systole and internal flow fraction during systole, were measured at rest and during controlled pre-load reduction sequences, as well as during 3 h of endotoxin infusion (0.25 ,g kg,1 h,1). Results:, Systolic dyssynchrony and internal flow fraction did not change during the course of acute beat-to-beat pre-load alteration. Endotoxin-produced acute pulmonary hypertension by left ventricular dyssynchrony measures was not changed during the early peak of pulmonary hypertension. Endotoxin ventricular injury led to progressive increases in systolic mechanical segmental dyssynchrony (7.9 ± 1.2,13.0 ± 1.3%) and ventricular systolic internal flow fraction (7.1 ± 2.4,16.6 ± 2.8%), respectively for baseline and then at hour 3. There was no localization of dyssynchrony changes to segment or region in the ventricular long axis during endotoxin infusion. Conclusion:, These results suggest that systolic mechanical dyssynchrony measures may be load independent in health and during acute global ventricular injury by endotoxin. More study is needed to validate ranges in health and disease for parameters of mechanical dyssynchrony. [source] Association of Coronary Sinus Diameter with Pulmonary HypertensionECHOCARDIOGRAPHY, Issue 9 2008Yilmaz Gunes M.D. Background: Impaired venous drainage secondary to increased right atrial pressure (RAP) may result in coronary sinus (CS) dilatation.,Methods: Two hundred fifteen patients referred for transthoracic echocardiography were included in the study. CS diameters were measured from apical four-chamber view with the transducer being slightly tilted posteriorly to the level of the dorsum of the heart. Pulmonary artery systolic pressure (PASP) is estimated by measurement of tricuspid regurgitation velocity (v) and estimate RAP based on size and collapsibility of inferior vena cava (VCI) with the formula PASP: 4v2+RAP. Patients with PASP >35 mmHg were considered to have pulmonary hypertension (PH).,Results: CS diameter was measured in 80.3% of the patients with normal PASP (8.1 ± 2.4 mm) and 93.1% of the patients having PH (12.3 ± 2.5 mm). PASP was significantly correlated with CS diameter (r = 0.647, P < 0.001), RA volume index (r = 0.631, P < 0.001), RV volume index (r = 0.475, P < 0.001), VCI diameter (r = 0.365, P < 0.001), and left ventricular ejection fraction (LVEF) (r =,0.270, P < 0.001). CS diameter was also correlated significantly with estimated RAP (r = 0.557, P < 0.001), RA volume index (r = 0.520, P < 0.001), RV volume index (r = 0.386, P < 0.001), LVEF (r =,0.327, P < 0.001), and VCI diameter (r = 0.313, P < 0.001). Multivariate analyses, testing for independent predictive information of CS size, VCI diameter, RA and RV volume indexes, and estimated RAP for the presence of PH revealed that estimated RAP (beta = 0.465, P < 0.001) and CS size (beta = 0.402, P = 0.003) were the significant predictors.,Conclusions: Coronary sinus is dilated in patients with pulmonary hypertension. Coronary sinus diameter significantly correlates with PASP, RAP, right heart chamber volumes, LVEF, and VCI diameter. [source] Doppler Superior Vena Cava Flow Evolution and Respiratory Variation in Superior Vena Cava SyndromeECHOCARDIOGRAPHY, Issue 4 2008Fa Qin Lv M.D. Background: Superior vena cava syndrome (SVCS) is a clinical expression of obstruction of blood flow through the superior vena cava. The patterns of the Doppler flow changes of superior vena cava (SVC), especially the respiratory effects on them have not yet been fully elucidated. This study was to examine SVC Doppler flow patterns and the respiratory effects on them in healthy subjects and patients with SVCS. Methods: The SVC Doppler flow patterns of 18 normal human subjects and 22 patients with SVCS were analyzed at initial diagnosis and were followed up every 2 months for at least 11 months. Results: Among the 22 patients, 5 patients with the tumor near the right atrium oppressing the inferior segment of the SVC had clear VR- and AR-waves, while in the other 17 patients the VR- and AR-waves disappeared or their outlines were vague. The respiratory variations of the S- and D-waves as a percentage change in inspiration compared to expiration in patient group were much lower than those in control group (S-wave: 1.67 ± 3.32% vs. 15.65 ± 16.15%, P = 0.0003; D-wave: 1.80 ± 1.12% vs. 23.55 ± 37%, P = 0.0087), which gradually became larger with treatment and showed no significant difference with those in control group after 7 months. Conclusions: The Doppler flows of the patients with SVCS correlate well with the images of CT scan of them. The respiratory variation of the S- and D-velocities could be used to evaluate the severity of SVC obstruction and its therapeutic effect. [source] Persistent Left-Sided Superior Vena Cava: Integrated Noninvasive DiagnosisECHOCARDIOGRAPHY, Issue 9 2007Antonino Recupero M.D. Persistent left superior vena cava (PLSVC) is a rare finding. We describe 5 patients with PLSVC diagnosed by a noninvasive approach, including two-dimensional (2D) echocardiogram, nuclear magnetic resonance and multislice computed tomography (MCT). In 4 cases the PLSVC was isolated ("alone PLSVC"), and in 1 case associated with a right superior vena cava. [source] Right Coronary Artery Hepatic Vein Fistula: A Case ReportECHOCARDIOGRAPHY, Issue 10 2006Sevket Gorgulu M.D. There is a slight predominance for coronary artery fistulas that involve the right coronary artery, while multiple fistulas have also been reported. The usual site of termination is one or more of the low-pressure structures in the heart or the great vessels such as the right or left atria, right ventricle, coronary sinus, pulmonary artery, or superior vena cava. However, a coronary fistula that drains into a hepatic vein has not been reported in the literature. Therefore, this is the first case report indicating a right coronary artery fistula that drains into the middle hepatic vein. [source] Fibrosing TB Mediastinitis Presenting as a Superior Vena Cava Syndrome: A Case Presentation and Echocardiogram CorrelateECHOCARDIOGRAPHY, Issue 7 2006Lidiette Esquivel M.D. A 49-year-old woman developed a chronic obstruction of the superior vena cava (SVC) as a complication of mediastinal tuberculosis. Echocardiography findings are presented along with the cavography. Symptoms disappeared after stenting the fibrosed SVC. Transesophageal echocardiogram findings led to the condition's final resolution. [source] Renal Adenocarcinoma with Intramyopericardial and Right Atrial Metastasis, Latter via Coronary Sinus: Report of a CaseECHOCARDIOGRAPHY, Issue 4 2005Morteza Rohani M.D. Primary renal tumors with intracardiac metastasis are not infrequent. Most of the secondary spread is blood-borne and occurs via inferior vena cava. Patients with such a spread often present with cardiac symptoms. We presume that a metastatic spread in the right atrium through coronary sinus has never been reported in the literature according to the result of a Medline search at the time of writing this report. [source] Drainage of the Inferior Vena Cava to the Left AtriumECHOCARDIOGRAPHY, Issue 2 2003Haran Burri M.D. Drainage of the inferior vena cava to the left atrium is an extremely unusual congenital heart disease. We describe a 54-year-old woman, in whom the diagnosis was suggested by transthoracic echocardiography, and then confirmed by a transesophageal exam and magnetic resonance imaging, which also revealed an associated secundum atrial septal defect. Surgical management involved reconstruction of the interatrial septum to include the inferior vena cava in the right atrium. The few previously reported cases in the literature are reviewed. (ECHOCARDIOGRAPHY, Volume 20, February 2003) [source] Angiotensin-(1,7) has a dual role on growth-promoting signalling pathways in rat heart in vivo by stimulating STAT3 and STAT5a/b phosphorylation and inhibiting angiotensin II-stimulated ERK1/2 and Rho kinase activityEXPERIMENTAL PHYSIOLOGY, Issue 5 2008Jorge F. Giani Angiotensin (ANG) II contributes to cardiac remodelling by inducing the activation of several signalling molecules, including ERK1/2, Rho kinase and members of the STAT family of proteins. Angiotensin-(1,7) is produced in the heart and inhibits the proliferative actions of ANG II, although the mechanisms of this inhibition are poorly understood. Accordingly, in the present study we examined whether ANG-(1,7) affects the ANG II-mediated activation of ERK1/2 and Rho kinase, STAT3 and STAT5a/b in rat heart in vivo. We hypothesized that ANG-(1,7) inhibits these growth-promoting pathways, counterbalancing the trophic action of ANG II. Solutions of normal saline (0.9% NaCl) containing ANG II (8 pmol kg,1) plus ANG-(1,7) in increasing doses (from 0.08 to 800 pmol kg,1) were administered via the inferior vena cava to anaesthetized male Sprague,Dawley rats. After 5 min, hearts were removed and ERK1/2, Rho kinase, STAT3 and STAT5a/b phosphorylation was determined by Western blotting using phosphospecific antibodies. Angiotensin II stimulated ERK1/2 and Rho kinase phosphorylation (2.3 ± 0.2- and 2.1 ± 0.2-fold increase over basal values, respectively), while ANG-(1,7) was without effect. The ANG II-mediated phosphorylation of ERK1/2 and Rho kinase was prevented in a dose-dependent manner by ANG-(1,7) and disappeared in the presence of the Mas receptor antagonist d -Ala7 -ANG-(1,7). Both ANG II and ANG-(1,7) increased STAT3 and STAT5a/b phosphorylation to a similar extent (130,140% increase). The ANG-(1,7)-stimulated STAT phosphorylation was blocked by the AT1 receptor antagonist losartan and not by d -Ala7 -ANG-(1,7). Our results show a dual action of ANG-(1,7), that is, a stimulatory effect on STAT3 and 5a/b phosphorylation through AT1 receptors and a blocking action on ANG II-stimulated ERK1/2 and Rho kinase phosphorylation through Mas receptor activation. The latter effect could be representative of a mechanism for a protective role of ANG-(1,7) in the heart by counteracting the effects of locally generated ANG II. [source] The baroreflex is counteracted by autoregulation, thereby preventing circulatory instabilityEXPERIMENTAL PHYSIOLOGY, Issue 4 2004Roberto Burattini The aims of this study were (a) to apply in the animal with intact baroreflex a two-point method for estimation of overall, effective open-loop gain, G0e, which results from the combined action of baroregulation and total systemic autoregulation on peripheral resistance; (b) to predict specific baroreflex gain by correcting the effective gain for the autoregulation gain; and (c) to discuss why the effective gain is usually as low as 1,2 units. G0e was estimated from two measurements of both cardiac output, Q, and mean systemic arterial pressure, P: one in the reference state (set-point) and the other in a steady-state reached 1,3 min after a small cardiac output perturbation. In anaesthetized cats and dogs a cardiac output perturbation was accomplished by partial occlusion of the inferior vena cava and by cardiac pacing, respectively. Average (±s.e.m.) estimates of G0e were 1.4 ± 0.2 (n= 8) in the cat and 1.5 ± 0.4 (n= 5) in the dog. The specific baroreflex open-loop gain, G0b, found after correction for total systemic autoregulation, was 3.3 ± 0.4 in the cat and 2.8 ± 0.8 in the dog. A model-based analysis showed that, with G0e as low as 1.4, the closed-loop response of P to a stepwise perturbation in Q results in damped oscillations that disappear in about 1 min. The amplitude and duration of these oscillations, which have a frequency of about 0.1 Hz, increase with increasing G0e and cause instability when G0e is about 3. We conclude that autoregulation reduces the effectiveness of baroreflex gain by about 55%, thereby preventing instability of blood pressure response. [source] The need for venovenous bypass in liver transplantationHPB, Issue 3 2008Hamidreza Fonouni Abstract Since introduction of the conventional liver transplantation (CLTx) by Starzl, which was based on the resection of recipient inferior vena cava (IVC) along the liver, the procedure has undergone several refinements. Successful use of venovenous bypass (VVB) was first introduced by Shaw et al., although in recent decades there has been controversy regarding the routine use of VVB during CLTx. With development of piggyback liver transplantation (PLTx), the use of caval clamping and VVB is avoided, leading to fewer complications related to VVB. However, some authors still advocate VVB in PLTx. The great diversity among centers in their use of VVB during CLTx, or even along the PLTx technique, has led to confusion regarding the indication setting for VVB. For this reason, we present an overview of the use of VVB in CLTx, the target of patients for whom VVB could be beneficial, and the needs assessment of VVB for patients undergoing PLTx. Recent studies have shown that with the advancement of surgical skills, refinement of surgical techniques, and improvements in anesthesiology, there are only limited indications for doing CLTx with VVB routinely. PLTx with preservation of IVC can be performed in almost all primary transplants and in the majority of re-transplantations without the need for VVB. Nevertheless, in a few selective cases with severe intra-operative hemodynamic instability, or with a failed test of transient IVC occlusion, the application of VVB is still justifiable. These indications should be judged intra-operatively and the decision is based on each center's preference. [source] Techniques of orthotopic liver transplantationHPB, Issue 2 2004L Lladó Background Throughout the history of liver transplantation many improvements have been made in the field of surgical technique. It is beyond the scope of this paper to review all aspects of surgical technique in liver transplantation; thus, in this review we focus on the description of our current technique in most cases, which is orthotopic liver transplantation with preservation of the inferior vena cava and temporary portocaval shunt. We advocate this technique because it has been demonstrated that it achieves better haemodynamic stability during the anhepatic phase, transfusion can be reduced and renal function is improved. The different options for vascular anastomoses are described, particularly the options for arterial anastomoses in case of finding a non-adequate recipient hepatic artery. Technical possibilities for patients with preoperative portal vein thrombosis and the procedure in case of domino or sequential liver transplantation are further explained. [source] Catheter-related septic thrombosis of superior vena cava and right heart in a patient with active Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 12 2008J.S. Souza MD No abstract is available for this article. [source] | ||||||||||||||||||||||||||||||||||