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Wedge Pressure (wedge + pressure)
Kinds of Wedge Pressure Selected AbstractsPulmonary Venous Wedge Pressure Provides an Accurate Assessment of Pulmonary Artery Pressure in Children with a Bidirectional Glenn ShuntJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2003DANIEL H. GRUENSTEIN M.D. Purpose: In circulations with pulsatile pulmonary artery flow the pulmonary venous wedge pressure (PVWp) has been validated as a good estimate of pulmonary artery pressure (PAp), when PAp is low. The purpose of this study was to validate PVWp estimates of PAp in the less-pulsatile pulmonary circulation of children after bidirectional Glenn shunts. Methods: A retrospective study was performed of 22 simultaneous measurements of PVWp and PAp made during 20 catheterizations in 19 children who had undergone bidirectional Glenn procedures. The PAp was measured directly from the branch PA ipsilateral to the side of the PVWp, or in the SVC. Pulmonary resistance (Rp) was calculated with both PAp and PVWp, to assess the impact of PAp estimates on Rp determinations. Results: Patients ranged in age from 5 months to 10.7 years. There were a variety of univentricular cardiac malformations in the study group. Two children had antegrade pulmonary blood flow in addition to a bidirectional Glenn shunt. The mean PAp ranged from 4 to 14 mmHg, while mean PVWp ranged from 3 to 15 mmHg. Mean PVWp never differed from mean PAp by more than 3 mmHg. There was a significant linear relation between mean PAp and PVWp: PAp = 0.86 (PVWp) + 2.0 (R2= 0.89; P < 0.0001). PVWp provided a good approximation of PAp regardless of the presence (n = 2) or absence (n = 19) of antegrade pulmonary flow. There was a good linear correlation between the Rp calculated by both methods (RpPAp = 0.9 (RpVWp) + 0.5; R2= 0.74; P < 0.0001). Conclusion: The mean PVWp provides a close approximation of mean PAp in children with a bidirectional Glenn shunt and provides valuable hemodynamic information in cases where direct PAp measurements are unavailable. (J Interven Cardiol 2003;16:367,370) [source] Invasive and Noninvasive Correlations of B-Type Natriuretic Peptide in Patients With Heart Failure Due to Chagas CardiomyopathyCONGESTIVE HEART FAILURE, Issue 3 2008Fábio Vilas-Boas MD Heart failure due to Chagas cardiomyopathy (HFCC) differs from failure with other etiologies because of the occurrence of intense inflammatory infiltrate and right ventricle compromise. This article investigates correlations of B-type natriuretic peptide (BNP) levels with parameters of severity in HFCC. Twenty-eight patients and 8 normal controls underwent heart catheterization and clinical and laboratory analyses. BNP levels were higher in patients with HFCC (P<.0001) and correlated with New York Heart Association (NYHA) class; right atrial pressure; wedge pressure; cardiac output; levels of serum sodium, hemoglobin, urea, and tumor necrosis factor-,; and ejection fraction. Interferon-, and transforming growth factor-, did not correlate with BNP level. The authors conclude that BNP levels are elevated in patients experiencing HFCC, irrespective of NYHA class, and that the occurrence of HFCC correlates with severity of disease. [source] Clinical and Hemodynamic Effects of Nesiritide (B-Type Natriuretic Peptide) in Patients With Decompensated Heart Failure Receiving , BlockersCONGESTIVE HEART FAILURE, Issue 2 2005William T. Abraham MD The use of , blockers in congestive heart failure presents a therapeutic challenge for patients with acute episodes of decompensation. Such patients may be less responsive to positive inotropic agents, whereas the beneficial effects of nesiritide, which are not dependent on the ,-adrenergic receptor signal-transduction pathway, may be preserved. This analysis of the Vasodilation in the Management of Acute CHF trial evaluated the safety and efficacy of nesiritide in decompensated congestive heart failure patients receiving , blockers. The Vasodilation in the Management of Acute CHF trial was a multicenter, randomized, controlled evaluation of nesiritide in 489 hospitalized patients with decompensated congestive heart failure. One hundred twenty-three patients were on chronic ,-blocker therapy at enrollment (31 randomized to placebo, 50 to nesiritide, and 42 to nitroglycerin). Primary end points included pulmonary capillary wedge pressure and dyspnea evaluation at 3 hours. Patients receiving nesiritide, but not IV nitroglycerin, had significantly reduced pulmonary capillary wedge pressure vs. placebo at 3 hours regardless of ,-blocker use. The use of , blockers did not alter the beneficial effects of nesiritide on systemic blood pressure, heart rate, or dyspnea evaluation. In nesiritide-treated subjects, safety profiles were similar regardless of ,-blocker use. Thus, the clinical and hemodynamic benefits and safety of nesiritide are preserved in decompensated congestive heart failure patients receiving chronic , blockade. [source] Subtle Systolic Dysfunction May Be Associated with the Tendency to Develop Diastolic Heart Failure in Patients with Preserved Left Ventricular Ejection FractionECHOCARDIOGRAPHY, Issue 4 2009Hüseyin Sürücü M.D. Background: We looked for an answer to the question of whether diastolic heart failure (DHF) is a reality or all heart failures are systolic. Method: 300 cases (hypertensive, aged, obese, etc.), not being diagnosed DHF, with preserved left ventricular (LV) ejection fraction (EF) but having the tendency to develop DHF in future were examined. One hundred and eighty cases without exclusion criteria were selected. Cases were assigned to three groups according to noninvasively obtained pulmonary capillary wedge pressure (PCWP). Results: In cases with higher PCWP (>10 mmHg), transmitral A velocity was increased (P < 0.001) and among the pulsed wave tissue Doppler imaging (pw-TDI) parameters Ea velocity was decreased (P < 0.001) and Ea-dt was prolonged (P < 0.005). In cases with lower PCWP (<8 mmHg), transmitral E velocity was higher (P< 0.001). Furthermore, a more meaningful relationship was found between PCWP and systolic pw-TDI parameters. In all the groups, it was observed that Sa velocity was progressively decreased and Q-Sa interval was progressively prolonged as PCWP increased (for all the groups P < 0.046). Conclusion: The question whether DHF is a reality or all heart failures are systolic may be answered as follows. Subtle systolic dysfunction may be associated with the tendency to develop DHF in patients with preserved LV ejection fraction. As in systolic heart failure (EF < 45%), in patients with preserved systolic function (EF , 45%), systolic and diastolic functions may impair together. The pw-TDI method may be more sensitive than standard echocardiography parameters in detection of systolic dysfunction in cases with preserved EF. [source] Clinical risk factors for portopulmonary hypertension,HEPATOLOGY, Issue 1 2008Steven M. Kawut Portopulmonary hypertension affects up to 6% of patients with advanced liver disease, but the predictors and biologic mechanism for the development of this complication are unknown. We sought to determine the clinical risk factors for portopulmonary hypertension in patients with advanced liver disease. We performed a multicenter case-control study nested within a prospective cohort of patients with portal hypertension recruited from tertiary care centers. Cases had a mean pulmonary artery pressure > 25 mm Hg, pulmonary vascular resistance > 240 dynes · second · cm,5, and pulmonary capillary wedge pressure , 15 mm Hg. Controls had a right ventricular systolic pressure < 40 mm Hg (if estimable) and normal right-sided cardiac morphology by transthoracic echocardiography. The study sample included 34 cases and 141 controls. Female sex was associated with a higher risk of portopulmonary hypertension than male sex (adjusted odds ratio = 2.90, 95% confidence interval 1.20-7.01, P = 0.018). Autoimmune hepatitis was associated with an increased risk (adjusted odds ratio = 4.02, 95% confidence interval 1.14-14.23, P = 0.031), and hepatitis C infection was associated with a decreased risk (adjusted odds ratio = 0.24, 95% confidence interval 0.09-0.65, P = 0.005) of portopulmonary hypertension. The severity of liver disease was not related to the risk of portopulmonary hypertension. Conclusion: Female sex and autoimmune hepatitis were associated with an increased risk of portopulmonary hypertension, whereas hepatitis C infection was associated with a decreased risk in patients with advanced liver disease. Hormonal and immunologic factors may therefore be integral to the development of portopulmonary hypertension. (HEPATOLOGY 2008.) [source] The clinical value of rapid assay for plasma B-type natriuretic peptide in differentiating congestive heart failure from pulmonary causes of dyspnoeaINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2008S.-Q. Zhao Summary Background:, B-type natriuretic peptide (BNP) is a cardiac neurohormone secreted from the cardiac ventricles in response to pressure overload. Objective:, To evaluate the optimal cutoff point of plasma BNP in diagnosing congestive heart failure (CHF). Methods:, We conducted a prospective study of 195 patients who were hospitalised with dyspnoea. Pulmonary capillary wedge pressure (PCWP) was measured with a Swan-Ganz catheterisation and plasma BNP level was obtained by a rapid immunofluorescence assay in all patients. PCWP > 12 mmHg was chosen as the golden standard for left ventricular dysfunction in this study. The subjects were divided into two groups by the criteria, one group with dyspnoea caused by CHF (n = 134) and the other caused by lung diseases (n = 61). Results:, (1) BNP cutoff point of 100 pg/ml had a sensitivity of 94.34%, a specificity of 92.13% and an accuracy of 93.33% for differentiating CHF from pulmonary dyspnoea. (2) By multiple logistic-regression analysis, measurements of BNP added significantly independent predictive power to other clinical variables in models predicting which patients had CHF. Conclusion:, A value of 100 pg/ml or more for a rapid BNP assay may be the most accurate independent predictor of the presence or absence of CHF. [source] Global and right ventricular end-diastolic volumes correlate better with preload after correction for ejection fractionACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2010M. L. N. G. MALBRAIN Background: Volumetric monitoring with right ventricular end-diastolic volume indexed (RVEDVi) and global end-diastolic volume indexed (GEDVi) is increasingly being suggested as a superior preload indicator compared with the filling pressures central venous pressure (CVP) or the pulmonary capillary wedge pressure (PCWP). However, static monitoring of these volumetric parameters has not consistently been shown to be able to predict changes in cardiac index (CI). The aim of this study was to evaluate whether a correction of RVEDVi and GEDVi with a measure of the individual contractile reserve, assessed by right ventricular ejection fraction (RVEF) and global ejection fraction, improves the ability of RVEDVi and GEDVi to monitor changes in preload over time in critically ill patients. Methods: Hemodynamic measurements, both by pulmonary artery and by transcardiopulmonary thermodilution, were performed in 11 mechanically ventilated medical ICU patients. Correction of volumes was achieved by normalization to EF deviation from normal EF values in an exponential fashion. Data before and after fluid administration were obtained in eight patients, while data before and after diuretics were obtained in seven patients. Results: No correlation was found between the change in cardiac filling pressures (,CVP, ,PCWP) and ,CI (R2 0.01 and 0.00, respectively). Further, no correlation was found between ,RVEDVi or ,GEDVi and ,CI (R2 0.10 and 0.13, respectively). In contrast, a significant correlation was found between ,RVEDVi corrected to RVEF (,cRVEDVi) and ,CI (R2 0.64), as well as between ,cGEDVi and ,CI (R2 0.59). An increase in the net fluid balance with +844 ± 495 ml/m2 resulted in a significant increase in CI of 0.5 ± 0.3 l/min/m2; however, only ,cRVEDVi (R2 0.58) and ,cGEDVi (R2 0.36) correlated significantly with ,CI. Administration of diuretics resulting in a net fluid balance of ,942 ± 658 ml/m2 caused a significant decrease in CI with 0.7 ± 0.5 l/min/m2; however, only ,cRVEDVi (R2 0.80) and ,cGEDVi (R2 0.61) correlated significantly with ,CI. Conclusion: Correction of volumetric preload parameters by measures of ejection fraction improved the ability of these parameters to assess changes in preload over time in this heterogeneous group of critically ill patients. [source] Evaluation of Left Ventricular Diastolic Function after Edge-to-Edge Mitral Valve PlastyJOURNAL OF CARDIAC SURGERY, Issue 1 2010Yong-Qiang Lai M.D. This procedure anchors the correspondence leaflets to create a double-orifice mitral valve. The original mitral valve anatomy is changed, and the opening of mitral valve is restricted. Little is known whether this procedure affects the left ventricular diastolic function. Methods: Thirty patients with mitral regurgitation were included in this study. Fifteen with posterior leaflet prolapse received quadrangular resection (group 1), 15 with anterior or bileaflet prolapse underwent edge-to-edge procedure (group 2). Acute hemodynamics was monitored with a Swan-Ganz catheter (Edwards Lifesciences LLC, Irvine, CA, USA). Left ventricular diastolic function was also evaluated with echocardiography in 28 patients with sinus rhythm. The ratio of peak E velocity and A velocity (E/A), the ratio of early diastolic peak flow velocity to early diastolic mitral annular movement velocity (E/Em), and the ratio of early diastolic mitral annular velocity to late diastolic mitral annular velocity (Em/Am) were measured before operation and one week after operation. Results: Mitral valve area and mitral regurgitate grade decreased significantly after operation. There was no significant change in pulmonary artery wedge pressure between two groups and in each group before and after operation. Echocardiography evaluation showed there was no significant difference in E/A, E/Em, and Em/Am before and after operation between two groups and in each group. Conclusion: Edge-to-edge mitral valve plasty procedure has no significant impairment on left ventricular diastolic function. A double-orifice mitral valve has similar hemodynamic behavior with a physiological valve.(J Card Surg 2010;25:5-8) [source] Pulmonary Venous Wedge Pressure Provides an Accurate Assessment of Pulmonary Artery Pressure in Children with a Bidirectional Glenn ShuntJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2003DANIEL H. GRUENSTEIN M.D. Purpose: In circulations with pulsatile pulmonary artery flow the pulmonary venous wedge pressure (PVWp) has been validated as a good estimate of pulmonary artery pressure (PAp), when PAp is low. The purpose of this study was to validate PVWp estimates of PAp in the less-pulsatile pulmonary circulation of children after bidirectional Glenn shunts. Methods: A retrospective study was performed of 22 simultaneous measurements of PVWp and PAp made during 20 catheterizations in 19 children who had undergone bidirectional Glenn procedures. The PAp was measured directly from the branch PA ipsilateral to the side of the PVWp, or in the SVC. Pulmonary resistance (Rp) was calculated with both PAp and PVWp, to assess the impact of PAp estimates on Rp determinations. Results: Patients ranged in age from 5 months to 10.7 years. There were a variety of univentricular cardiac malformations in the study group. Two children had antegrade pulmonary blood flow in addition to a bidirectional Glenn shunt. The mean PAp ranged from 4 to 14 mmHg, while mean PVWp ranged from 3 to 15 mmHg. Mean PVWp never differed from mean PAp by more than 3 mmHg. There was a significant linear relation between mean PAp and PVWp: PAp = 0.86 (PVWp) + 2.0 (R2= 0.89; P < 0.0001). PVWp provided a good approximation of PAp regardless of the presence (n = 2) or absence (n = 19) of antegrade pulmonary flow. There was a good linear correlation between the Rp calculated by both methods (RpPAp = 0.9 (RpVWp) + 0.5; R2= 0.74; P < 0.0001). Conclusion: The mean PVWp provides a close approximation of mean PAp in children with a bidirectional Glenn shunt and provides valuable hemodynamic information in cases where direct PAp measurements are unavailable. (J Interven Cardiol 2003;16:367,370) [source] Determinants of Serum Creatinine Trajectory in Acute Contrast NephropathyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2002NOEL V. GUTTTEREZ M.D. The aim of this study was to describe the trajectory of creatinine (Cr) rise and its determinants after exposure to radiocontrast media. Included were 98 subjects who underwent cardiac catheterization and were randomized to forced diuresis with IV crystalloid, furosemide, mannitol (if pulmonary capillary wedge pressure was<20 mmHg), and low dose dopamine versus intravenous crystalloid and matching placebos. Baseline and postcatheterization serum Cr levels were analyzed in a longitudinal fashion, allowing for differences in the time between blood draws, to determine the different critical trajectories of serum Cr. The mean age, baseline serum Cr, and Cr clearance (CrCl) were 69.3 ± 10.8 years, 2.5 ± 0.9 mg/dL, and 31.4 ± 12.1 mL/min, respectively. The clinically driven postprocedural observation time was 5.5 ± 5.1 days (range 19 hours and one Cr value to 25.7 days and 18 values). The mean maximum Cr was 3.3 ± 1.4, range 1.7,8.7 mg/dL). Longitudinal models support baseline Cr clearance predictions for the change in Cr at 24 hours, time as the determinant of Cr trajectory, and requisite monitoring. For any given individual, a rise in Cr of , 0.5 mg/dL in the first 24 hours after contrast exposure predicted a favorable outcome. Baseline renal function is the major determinant of the rate of rise, height, and duration of Cr trajectory after contrast exposure. Length of observation and frequency of laboratory measures can be anticipated from these models. [source] Haemodynamics in leptospirosis: Effects of plasmapheresis and continuous venovenous haemofiltrationNEPHROLOGY, Issue 1 2005TONGPRAKOB SIRIWANIJ SUMMARY: Background: Haemodynamics in leptospirosis may differ from that of sepsis because of frequently obeserved myocarditis and severe cholestatic jaundice. A haemodynamic study was therefore made in 10 patients with severe leptospirosis. Methods and Results: All patients had pulmonary complications with a chest X-ray showing either pulmonary oedema or infiltration. Renal failure was present in nine patients. Three patterns of haemodynamics were revealed. The first pattern was observed in six patients who showed increased cardiac index, decreased systemic vascular resistance, normal pulmonary capillary wedge pressure, normal pulmonary vascular resistance and hypotension. The pattern resembled that of sepsis. The second pattern shown in two patients with haemoptysis consisted of a normal cardiac index, normal systemic vascular resistance, normal blood pressure, normal pulmonary capillary wedge pressure and increased pulmonary vascular resistance. The third pattern was observed in two patients with severe jaundice who had hypotension, a relatively low cardiac index, increased systemic vascular resistance and normal pulmonary capillary wedge pressure, and pulmonary vascular resistance. Plasmapheresis performed in two patients and continuous venovenous haemofiltration performed in two patients improved systemic haemodynamics and normalized blood pressure with a resolution of lung signs. [source] Blunted effect of the Kv channel inhibitor on pulmonary circulation in Tibetan sheep: A model for studying hypoxia and pulmonary artery pressure regulationRESPIROLOGY, Issue 1 2004Takeshi Ishizaki Objective: The aim of this study was to assess the effect of 4-aminopyridine, a Kv channel inhibitor, on the pulmonary circulation of Tibetan sheep. It has been reported that chronic hypoxia downregulates the 4-aminopyridine (4AP)-sensitive Kv channel (which governs the membrane potential (Em) of pulmonary vascular smooth muscle cells in pulmonary vessels) without a change in 4AP sensitivity. Methodology: Pulmonary haemodynamic indices and blood gas analyses were measured in six young male animals in an altitude chamber that was adjusted to simulated altitudes of 0 m, 2260 m, and 4500 m. Drip infusion of 4AP, 10 mg/h for 3 h, was started and continued during the study. Results: With the increase in altitude mean pulmonary artery pressure increased and mean Pao2 decreased. 4AP had no effect on the levels of mean PPA, mean pulmonary artery wedge pressure, cardiac output, and mean PaO2, mean PaCO2, and mean pH at any altitude but tended to alter heart rate and mean arterial pressure at altitudes of 2260 m and 4500 m. Conclusion: It is concluded that the 4AP-sensitive Kv channel does not play a role in pulmonary vascular tone in high-altitude active Tibetan sheep. Their pulmonary vascular oxygen sensing appears not to involve Kv channels. [source] Hemodynamic Changes in a Model of Chronic Heart Failure Induced by Multiple Sequential Coronary Microembolization in SheepARTIFICIAL ORGANS, Issue 11 2009Jan Dieter Schmitto Abstract Although a large variety of animal models for acute ischemia and acute heart failure exist, valuable models for studies on the effect of ventricular assist devices in chronic heart failure are scarce. We established a stable and reproducible animal model of chronic heart failure in sheep and aimed to investigate the hemodynamic changes of this animal model of chronic heart failure in sheep. In five sheep (n = 5, 77 ± 2 kg), chronic heart failure was induced under flouroscopic guidance by multiple sequential microembolization through bolus injection of polysterol microspheres (90 µm, n = 25.000) into the left main coronary artery. Coronary microembolization (CME) was repeated up to three times in 2 to 3-week intervals until animals started to develop stable signs of heart failure. During each operation, hemodynamic monitoring was performed through implantation of central venous catheter (central venous pressure [CVP]), arterial pressure line (mean arterial pressure [MAP]), implantation of a right heart catheter {Swan-Ganz catheter (mean pulmonary arterial pressure [PAPmean])}, pulmonary capillary wedge pressure (PCWP), and cardiac output [CO]) as well as pre- and postoperative clinical investigations. All animals were followed for 3 months after first microembolization and then sacrificed for histological examination. All animals developed clinical signs of heart failure as indicated by increased heart rate (HR) at rest (68 ± 4 bpm [base] to 93 ± 5 bpm [3 mo][P < 0.05]), increased respiratory rate (RR) at rest (28 ± 5 [base] to 38 ± 7 [3 mo][P < 0.05]), and increased body weight 77 ± 2 kg to 81 ± 2 kg (P < 0.05) due to pleural effusion, peripheral edema, and ascites. Hemodynamic signs of heart failure were revealed as indicated by increase of HR, RR, CVP, PAP, and PCWP as well as a decrease of CO, stroke volume, and MAP 3 months after the first CME. Multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with clinical and hemodynamic signs of chronic ischemic cardiomyopathy. The present model may be suitable in experimental work on heart failure and left ventricular assist devices, for example, for studying the impact of mechanical unloading, mechanisms of recovery, and reverse remodeling. [source] Plasma Exchange Before Surgery for Left Ventricular Assist Device ImplantationARTIFICIAL ORGANS, Issue 6 2008Rajko Radovancevic Abstract:, Left ventricular assist device (LVAD) implantation in end-stage heart failure patients is frequently associated with hemorrhagic complications requiring reoperation. The preoperative coagulopathic profile includes prolonged prothrombin time (PT), partial thromboplastin time (PTT), and bleeding time; platelet dysfunction; decreased coagulation factor activity; and increased inflammatory markers. We compare outcomes in LVAD patients treated with preoperative plasma exchange with concurrent, nonrandomized control patients. We reviewed data from 68 consecutive elective patients who received LVADs at our institution. Thirty-five received LVADs after preoperative plasma exchange (replacement of one plasma volume of fresh frozen plasma), and 33 received LVADs without plasma exchange. Groups were comparable in age, sex, body weight, New York Heart Association class, intra-aortic balloon pump insertion, cardiac index, pulmonary capillary wedge pressure, creatinine, total bilirubin, hemoglobin levels, PT, international normalized ratio, PTT, and platelet count. Early mortality was lower in the plasma exchange group (0% [0/35] vs. 18% [6/33], P = 0.026), and postoperative chest tube drainage decreased by 33% (P = not significant). Blood transfusion requirements were similar.Perioperative mortality decreased in patients treated with plasma exchange before LVAD implantation. [source] Pulmonary venous wedge pressure provides a safe and accurate estimate of pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 5 2009Kevin D. Hill MD Abstract Objectives: To compare two methods of pulmonary arterial pressure measurement in children with shunt-dependent pulmonary blood flow. Background: In children with shunt-dependent pulmonary blood flow, direct assessment of pulmonary arterial pressure requires passage of a catheter across the shunt. This can be technically difficult and dangerous. Use of the pulmonary venous wedge pressure offers an alternative but has not been validated in this patient population. Methods: We prospectively studied 18 children with shunt-dependent pulmonary blood flow. Pulmonary venous wedge pressure and directly measured pulmonary arterial pressures were independently assessed by two blinded cardiologists. Results: Directly measured mean pulmonary arterial pressure and pulmonary venous wedge pressure are closely correlated (R2 = 0.80, P < 0.01). Agreement between the two measures is improved at lower mean pressures with greater differences at higher pressures. For 20 of 24 ipsilateral measurements, pulmonary venous wedge pressure was , directly measured pulmonary arterial pressure. Pulmonary venous wedge pressure never underestimated pulmonary arterial pressure by more than 3 mm Hg. Conclusions: Pulmonary venous wedge pressure provides a safe and accurate means of estimating pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow. The slightly lower pressures seen on direct measurement compared with the reverse pulmonary vein may reflect impairment of flow across the shunt by the catheter. © 2009 Wiley-Liss, Inc. [source] Catheter-based ventricle-coronary vein bypassCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005Motoya Hayase MD Abstract The goal of this study was to investigate the feasibility of a catheter-based ventricle-to-coronary vein bypass (VPASS) in order to achieve retrograde myocardial perfusion by a conduit (VSTENT) from the left ventricle (LV) to the anterior interventricular vein (AIV). Percutaneous coronary venous arterialization has been proposed as a potential treatment strategy for otherwise untreatable coronary artery disease. In an acute setting, the VSTENT implant was deployed percutaneously using the VPASS procedure in five swine. Coronary venous flow and pressure patterns were measured before and after VSTENT implant deployment with and without AIV and left anterior descending artery (LAD) occlusion. In a separate chronic pilot study, the VPASS procedure was completed on two animals that had a mid-LAD occlusion or LAD stenosis. At day 30 post-VPASS procedure, left ventriculography and magnetic resonance imaging (MRI) were performed to assess the patency and myocardial viability of the VSTENT implants. Pre-VSTENT implantation, the mid-AIV systolic wedge pressure was significantly lower than LV systolic pressure during AIV blockage (46 ± 19 vs. 90 ± 16 mm Hg; P < 0.01). The VSTENT implant deployment was performed without complication and achieved equalization of the AIV and LV systolic pressures and creation of retrograde flow in the distal AIV (maximal flow velocity: 37 ± 7 cm/sec). At day 30 post-VPASS procedure, left ventriculography showed VSTENT implant patency. MRI perfusion images demonstrated myocardial viability even with an LAD occlusion. Coronary retrograde perfusion using the VPASS procedure is feasible and may represent a potential technique for end-stage myocardial ischemia. Catheter Cardiovasc Interv 2005. © 2005 Wiley-Liss, Inc. [source] EFFECT OF BAY 41-2272 IN THE PULMONARY HYPERTENSION INDUCED BY HEPARIN,PROTAMINE COMPLEX IN ANAESTHETIZED DOGSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2007Cristiane F Freitas SUMMARY 1BAY 41-2272 is a potent activator of the nitric oxide-independent site of soluble guanylate cyclase and has been recently introduced as a new therapeutic agent to treat chronic pulmonary hypertension (PH) in neonatal sheep. Because the in vivo heparin,protamine interaction may lead to severe PH, the aim of the present study was to evaluate the effects of BAY 41-2272 in the PH induced by heparin,protamine interaction in anaesthetized dogs. 2Sixteen male dogs (10 mongrel dogs and six Beagles) were anaesthetized and instrumented for acquisition of mean arterial blood pressure (MABP), mean pulmonary arterial pressure (MPAP), heart rate (HR), pulmonary capillary wedge pressure (PCWP), cardiac index (CI) and indices of systemic and pulmonary vascular resistance (ISVR and IPVR, respectively). Plasma cGMP levels and Spo2 were evaluated. 3Intravenous administration of heparin (500 IU/kg) followed 3 min later by protamine (10 mg/kg) caused marked PH, as evaluated by the increase in MPAP, PCWP and IPVR. This was accompanied by a significant fall in MABP and a transient increase in HR. Infusion of BAY 41-2272 (10 µg/kg per h, starting 10 min before heparin administration) augmented plasma cGMP levels and slightly and significantly increased HR and CI, without affecting the other cardiovascular parameters. The elevation in IPVR, MPAP and PCWP triggered by the heparin,protamine interaction was significantly reduced in animals exposed to BAY 41-2272. 4In vehicle-treated dogs, the Spo2 values decreased significantly at the peak of the PH and this was significantly attenuated by treatment with BAY 41-2272. In addition, BAY 41-2272 (10 µmol/L) had no effect on the activated partial thromboplastin time of citrated plasma after the addition of heparin,protamine. 5In conclusion, BAY 41-2272 was effective in reducing canine PH induced in vivo by the heparin,protamine interaction, thus indicating its potential in the treatment of this type of disorder. [source] Normal values of pulmonary capillary wedge pressure and the blood pressure response to the Valsalva manoeuvre in healthy elderly subjectsCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 6 2005Jaap J. Remmen Summary The blood pressure response to the Valsalva manoeuvre is related to pulmonary capillary wedge pressure (PCWP) and can be used to diagnose heart failure. However, this has never been studied specifically in the elderly, in whom the prevalence of heart failure is highest. Furthermore, normal values of the Valsalva manoeuvre are lacking. We aimed to obtain normal values of PCWP and the blood pressure response to the Valsalva manoeuvre in elderly subjects. Therefore, 28 healthy subjects, aged 70 ± 4 years, performed Valsalva manoeuvres before and after anti-G garment inflation, which was used for temporary increase of PCWP. Before inflation, PCWP was 9·8 ± 1·9 mmHg in supine and 8·9 ± 2·1 in semi-recumbent position. From the blood pressure response, measured with Finapres, the systolic blood pressure ratio (SBPR), pulse pressure ratio (PPR), stroke volume ratio (SVR) and heart rate ratio (HRR) were calculated. In supine position, SBPR was 0·76 ± 0·11, PPR 0·51 ± 0·16, SVR 0·42 ± 0·11, and HRR 1·17 ± 0·12. Semi-recumbently, SBPR was 0·74 ± 0·10, PPR 0·46 ± 0·14, SVR 0·41 ± 0·10, and HRR 1·24 ± 0·23. After inflation of the anti-G garment, the areas under the Receiver Operator Characteristics curves of SBPR, PPR and SVR for elevated (,15 mmHg) PCWP were >0·85 in supine position. In conclusion, this is the first study to obtain normal values of the blood pressure response to the Valsalva manoeuvre and PCWP in healthy elderly subjects, which is essential for the interpretation of patient data. The Valsalva manoeuvre showed significant discriminatory power in the detection of elevated PCWP, which underscores its potential in the non-invasive diagnosis of heart failure. [source] |