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Artery Pressure (artery + pressure)
Kinds of Artery 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] Percutaneous Closure of a Large PDA in a 35-Year-Old Man with Elevated Pulmonary Vascular ResistanceCONGENITAL HEART DISEASE, Issue 2 2008John S. Hokanson MD ABSTRACT The presence of a large patent ductus arteriosus (PDA) may result in significant pulmonary hypertension, which may not be reversible. We present the case of a 35-year-old man with pulmonary hypertension who had successful percutaneous closure of a large PDA with an Amplatzer muscular ventricular septal defect occluder and resolution of his pulmonary hypertension. The use of prior balloon test occlusion of the PDA suggested that the procedure would be successful, despite the lack of an immediate fall in the pulmonary artery pressure. [source] Identifying Left Ventricular Dysfunction in Pulmonary HypertensionCONGESTIVE HEART FAILURE, Issue 5 2009Navin Rajagopalan MD The significance of left ventricular (LV) dysfunction in patients with pulmonary hypertension (PH) is unknown. Our purpose was to quantify LV function in PH patients by measuring LV myocardial performance index (MPI) and correlating it with invasively determined hemodynamic variables. The authors prospectively measured LV MPI via transthoracic echocardiography in 50 patients with PH (53±11 years; 35 women) who also underwent right heart catheterization within 1 day of echocardiography. For comparative purposes, LV MPI was also measured in 15 healthy volunteers who served as controls. LV MPI was significantly increased in the PH group compared with controls (0.62±0.27 vs 0.36±0.08; P<.001), indicating worse LV dysfunction despite that LV ejection fraction was not significantly different between the groups (58%±4% vs 60%±3%). LV MPI demonstrated significant correlations with invasively determined mean pulmonary artery pressure (r=.50; P<.001), pulmonary vascular resistance (r=.57; P<.001), and cardiac index (r=,.64; P<.001). By receiver operating characteristic analysis, LV MPI >0.75 predicted cardiac index <2 L/min/m2 with 89% sensitivity and 78% specificity (area under the curve, 0.89). In a multivariate model, LV MPI was independently associated with cardiac index (P<.01). Patients with PH demonstrate abnormal LV function as quantified by elevated LV MPI, which correlates significantly with pulmonary vascular resistance and cardiac index. [source] Hepatopulmonary Syndrome and Right Ventricular Diastolic Functions: An Echocardiographic ExaminationECHOCARDIOGRAPHY, Issue 4 2006Aziz Karabulut M.D. Aim: Liver functions are affected in the course of cardiac diseases, and similarly, liver diseases affect cardiac functions. Many studies in the literature have shown that left ventricular systolic and/or diastolic dysfunction may develop during chronic liver disease. However, there are limited studies investigating right ventricular functions during chronic liver diseases. Methods: A total of 84 patients who had no systolic and/or diastolic dysfunction in the left ventricle (LV) were evaluated; 46 patients with liver cirrhosis; 10 (21.74%) cirrhotic patients with hepatopulmonary syndrome (HPS) (group 1), 36 (78.26) cirrhotic patients without HPS (group 2), and 38 healthy individuals were treated as control. Results: Right ventricular diastolic dysfunction was determined in all patients of group 1 (100%), 26 of group 2 (72.22 %), and 4 of the controls (10.52%) (P < 0.05). Tricuspid deceleration time (dt) was significantly different between the groups (P < 0.05). In addition, right atrium (RA) diameters, right ventricle (RV) diameters, and RV wall thickness were significantly different between the groups (P < 0.05). Pulmonary artery pressure (P < 0.05) and pulmonary vascular resistance (P < 0.05) were also seen to be higher in group 1 than those in group 2 and control group. Conclusions: Right ventricular diastolic dysfunction rate is high in chronic liver diseases. In the presence of HPS, right ventricular diastolic dysfunction is more remarkable in patients than those without HPS. Right ventricular diastolic dysfunction may result in dilatation and hypertrophy in the right heart. [source] Effects of phlebotomy on haemodynamic characteristics during exercise in Standardbred trotters with red cell hypervolaemiaEQUINE VETERINARY JOURNAL, Issue 4 2001P. FUNKQUIST Summary Five Standardbred trotters with red cell hypervolaemia (RCHV) were compared before and after removal of approximately 22% (36 ml/kg bwt) of the total blood volume in order to evaluate the haemodynamic responses, haemorheological alterations and oxygen transport during exercise to fatigue. Data were recorded during submaximal exercise at 4 different speeds on a treadmill and then during continued running at the highest speed step until fatigue. Oxygen uptake (V,O2), pulmonary artery pressure (PAP), systemic artery pressure (SAP), heart rate (HR), haematocrit and haemoglobin concentrations (Hb) were measured. Arteriovenous O2 content difference (C(a-v,)O2), pulmonary vascular resistance (PVR) and total systemic resistance (TSR) were calculated. Whole blood and plasma viscosity and erythrocyte aggregation tendency were determined with a rotational viscometer. Endoscopy was performed after exercise. ANOVA was used for statistical analysis. Phlebotomy resulted in a decrease in haematocrit and Hb during the course of exercise. Blood and plasma viscosity were lower and erythrocyte aggregation tendency was higher after phlebotomy. Throughout exercise, including submaximal work and continued running to fatigue, PAP, SAP, PVR, TSR and C(a-v,)O2 were lower after phlebotomy. HR was higher after phlebotomy during submaximal exercise. Oxygen delivery and VO2 were lower after phlebotomy in the period from submaximal exercise to fatigue. Run time to fatigue was shorter after phlebotomy. Four horses showed exercise-induced pulmonary haemorrhage (EIPH) before phlebotomy and the degree of bleeding was diminished but not abolished after phlebotomy. The reductions in PVR, TSR, PAP and SAP after phlebotomy were probably a result of reduced blood viscosity. In conclusion, although a 22% reduction in blood volume improved the haemodynamic and haemorheological parameters and the degree of EIPH, it was found that RCHV trotters have to rely on high oxygen delivery to the working muscles for maintenance of maximal performance. [source] Impaired aortic elastic properties in patients with systemic sarcoidosisEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2008I. Moyssakis Abstract Background, Systemic sarcoidosis (Sar) is a granulomatous disorder involving multiple organs. Widespread vascular involvement and microangiopathy are common in patients with Sar. In addition, subclinical cardiac involvement is increasingly recognized in patients with Sar. However, data on the effect of Sar on the elastic properties of the arteries and myocardial performance are limited. In this study we looked for differences in aortic distensibility (AoD) which is an index of aortic elasticity, and myocardial performance of the ventricles, between patients with Sar and healthy subjects. In addition, we examined potential associations between AoD and clinical, respiratory and echocardiographic findings in patients with Sar. Materials and methods, A total of 83 consecutive patients (26 male/57 female, mean age 51·1 ± 13·3 years) with Sar, without cardiac symptoms, were included. All patients underwent echocardiographic and respiratory evaluation including lung function tests. Additionally, 83 age- and sex-matched healthy subjects served as controls. AoD was determined non-invasively by ultrasonography. Results, AoD was lower in the Sar compared to the control group (2·29 ± 0·26 vs. 2·45 ± 0·20 ·10,6 cm2· dyn,1, P < 0·01), while left ventricular mass (LVM) was higher in the Sar group (221·3 ± 50·2 vs. 195·6 ± 31·3 g, P = 0·007). Furthermore, myocardial performance of both ventricles was impaired in the Sar group. Multivariate linear regression analysis in the total sample population demonstrated a significant and independent inverse relationship between AoD and the presence of Sar (P < 0·001). The same analysis in the Sar patients showed that AoD was associated significantly and independently with the stage of Sar, age, systolic blood pressure, LVM and myocardial performance of both ventricles. No significant relationship was found between AoD and disease duration, pulmonary artery pressure or lung function tests. Conclusions, Presence and severity of Sar are associated with reduced aortic distensibility, irrespective of the disease duration, pulmonary artery pressure and lung function. In addition, patients with Sar have increased LVM and impaired myocardial performance. [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] Evaluation of Interventions Proposed for Altered Tissue Perfusion: Cardiopulmonary in Patients Hospitalized With Acute Myocardial InfarctionINTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 2003Ivanise Maria Gomes PURPOSE To evaluate the effectiveness and efficacy of the interventions proposed for patients with altered tissue perfusion: cardiopulmonary, according to NIC and NOC taxonomies. METHODS Prospective and descriptive study carried out in the cardiology unit of a school hospital with patients under clinical treatment followed from admission until discharge. Patient data were collected using the unit's assessment tool and nursing diagnoses were established. Daily activities were proposed for these patients based on NIC interventions "cardiac care: acute,""cardiac care," and "cardiac care: rehabilitative." Results were evaluated according to indicators selected from NOC's Tissue Perfusion: Cardiac. FINDINGS The sample comprised 25 patients (12 males, 13 females), age range 39 to 83 years. Days hospitalized averaged 3.5 in the coronary unit and 3.5 in the cardiology infirmary, for a total of 7 hospital days. The nursing diagnosis was made based on defining characteristics: enzymatic and ECG changes were found in 100% of the patients, chest pain (96%), diaphoresis (80%), and nausea (72%). The related factor in evidence for 100% of the sample was coronary arterial flow interruption. Patients were evaluated according to NOC outcomes both before starting activities and daily, with the following results: chest pain , 64% of patients initially presented pain with score 1, most (72%) presented scores 4 and 5 on day 2; on days 3, 5, 6, and 7 of hospitalization, all patients reported absence of pain (score 5). On day 4 only, 4% of patients reported pain with intensity 7 (score 2). Profuse diaphoresis was found in 80% of the sample on day 1 of hospitalization, and that disappeared in the course of the remaining days. Nausea was found in 44% of the population with score 1 on day 1 of hospitalization, and disappeared subsequently. Most the patients (84%) did not present with vomiting. Also, no evidence was found of vital sign changes in most of the sample. ECG presented score 1 in 72% of the sample on day 1, greatly decreasing from day 2. Cardiac enzymes appeared in 100% of the sample, decreasing in subsequent days. Heart ejection fraction, pulmonary artery pressure, heart rate, and myocardial scanning indicators were not measured. CONCLUSIONS Indicators evaluated achieved score 5 (no compromise) on hospital discharge in 100% of patients, which evidences effectiveness of the interventions performed. [source] Haemodynamic effects of ,75 mmHg negative pressure therapy in a porcine sternotomy wound modelINTERNATIONAL WOUND JOURNAL, Issue 1 2009Arash Mokhtari Abstract Previous research has shown ,125 mmHg to be the optimal negative pressure for creating an environment that promotes wound healing, and this has therefore been adopted as a standard pressure for patients with deep sternal wound infection. However, it has not yet been clearly shown that ,125 mmHg is the optimal pressure from a haemodynamic point of view. Furthermore, there have been reports of cardiac rupture during ,125 mmHg negative pressure therapy. We therefore studied the effects of a lower pressure: ,75 mmHg. Twelve pigs were used. After median sternotomy, sealed negative pressure therapy of ,75 mmHg was applied. Baseline measurements were made and continuous recording of the cardiac output, end-tidal CO2 production, mean arterial pressure, mean pulmonary pressure (pulmonary artery pressure), systemic vascular resistance, pulmonary vascular resistance, left atrial pressure and central venous pressure was started. Six pigs served as controls. No statistically significant difference was observed in any of the haemodynamic parameters studied, compared with the controls. The present study shows that, with a suitable foam application technique, ,75 mmHg can be applied without compromising the central haemodynamics. [source] Current treatment strategies for pulmonary arterial hypertensionJOURNAL OF INTERNAL MEDICINE, Issue 3 2005S. H. LEE Abstract., Lee SH, Rubin LJ (University of California, San Diego, La Jolla, CA, USA). Current treatment strategies for pulmonary arterial hypertension (Review). J Intern Med 2005; 258: 199,215. Pulmonary arterial hypertension (PAH) is a disease characterized by an elevation in pulmonary artery pressure that can lead to right ventricular failure and death. Although there is no cure for PAH, newer medical therapies have been shown to improve a variety of clinically relevant end-points including survival, exercise tolerance, functional class, haemodynamics, echocardiographic parameters and quality of life measures. Since the introduction of continuous intravenous prostacyclin, the treatment armamentarium of approved drugs for PAH has expanded to include prostacyclin analogues with differing routes of administration, a dual endothelin receptor antagonist, and a phosphodiesterase-5 inhibitor. Selective endothelin-A receptor antagonists have shown promise in clinical trials and are likely to be added to the list of options. As the number of medications available for PAH continues to increase, treatment decisions regarding first-line therapy, combination treatments, and add-on strategies are becoming more complex. This article reviews the current treatments strategies for PAH and provides guidelines for its management. [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] Cardiovascular and Pulmonary Effects of Hetastarch Plus Hypertonic Saline Solutions during Experimental Endotoxemia in Anesthetized HorsesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2006DACVIM, Lucas G. Pantaleon MV Background:Small volume resuscitation has been advocated as a beneficial therapy for endotoxemia in horses but this therapy has not been investigated in a prospective manner. The objective of this study was to determine the cardiopulmonary effects of small-volume resuscitation using hypertonic saline solution (HSS) plus Hetastarch (HES) during experimental endotoxemia in anesthetized horses. Hypothesis:Treatment of horses with induced endotoxemia using HES-HSS does not alter the response of various cardiopulmonary indices when compared to treatment with either small-or large-volume isotonic crystalloid solutions. Animals:Eighteen healthy horses were randomly assigned to 1 of 3 groups. Anesthesia was maintained with halothane. Endotoxemia was induced by administering 50 ,g/kg of Escherichia coli endotoxin IV. The horses were treated over 30 minutes with 15 mL/kg of balanced polyionic crystalloid solution (control), 60 mL/kg of balanced polyionic crystalloid solution (ISO), or 5 mL/kg of HSS followed by 10 mL/kg of HES (HSS-HES). Methods:Prospective randomized trial. Results:Cardiac output (CO) after endotoxin infusion increased significantly (P < .05) from baseline in all groups, whereas mean central venous pressure increased significantly (P < .05) in the ISO group only. Mean pulmonary artery pressure increased from baseline (P < .05) in horses treated with isotonic fluids and HSS-HES. There was no effect of treatment with HSS-HES on CO, systemic vascular resistance (SVR), mean arterial pressure, blood lactate concentrations, or arterial oxygenation. Conclusions and Clinical Importance: The use of HSS-HES failed to ameliorate the deleterious hemodynamic responses associated with endotoxemia in horses. The clinical value of this treatment in horses with endotoxemia remains unconfirmed. [source] Comparison of the USCOM ultrasound cardiac output monitor with pulmonary artery catheter thermodilution in patients undergoing liver transplantation,LIVER TRANSPLANTATION, Issue 7 2008Lai-Sze Grace Wong The aim of the study was to compare the standard technique of cardiac output determination by pulmonary artery catheter thermodilution (PAC-TD) with a noninvasive ultrasound Doppler monitor (USCOM Pty., Ltd., Coffs Harbour, Australia) in surgery for liver transplantation. We wished to determine if the degree of accuracy would allow the ultrasound cardiac output monitor (USCOM) to be used as an alternative monitor in a clinical setting in which wide fluctuations in cardiac output could be expected. This was a prospective method comparison study, with 71 paired measurements obtained in 12 patients undergoing liver transplantation in a university teaching hospital. Bland-Altman analysis of the 2 techniques showed a bias of 0.39 L/minute, with the USCOM cardiac output lower compared with that of PAC-TD. The bias was small and did not vary with the magnitude of the cardiac output. The 95% limits of agreement were ,1.47 and 2.25 L/minute. There was good repeatability for USCOM measurements, with a repeatability coefficient of 0.43 for USCOM versus 0.77 for PAC-TD. We conclude that USCOM is acceptable for the clinical determination of noninvasive cardiac output, particularly in situations in which tracking changes over time is more important than knowing the precise value. However, the utility of USCOM is limited by its inability to measure pulmonary artery pressure. Liver Transpl 14:1038,1043, 2008. © 2008 AASLD. [source] Development of pulmonary hypertension in 5 patients after pediatric living-donor liver transplantation: De novo or secondary?LIVER TRANSPLANTATION, Issue 5 2006Yasumasa Shirouzu The development of portopulmonary hypertension (PH) in a patient with end-stage liver disease is related to high cardiac output and hyperdynamic circulation. However, PH following liver transplantation is not fully understood. Of 617 pediatric patients receiving transplants between June 1990 and March 2004, 5 (median age 12 yr, median weight 24.5 kg) were revealed to have portopulmonary hypertension (PH) after living-donor liver transplantation (LDLT), as confirmed by echocardiography and/or right heart catheterization. All children underwent LDLT for post-Kasai biliary atresia. In 2 patients with refractory biliary complications, PH developed following portal thrombosis; 2 with stable graft function, who had had intrapulmonary shunting (IPS) before LDLT, were found to have PH in spite of overcoming liver dysfunction due to hepatitis. PH developed shortly after distal splenorenal shunting in 1 patient, who suffered liver cirrhosis due to an intractable outflow blockage. The onset of PH ranged from 2.8 to 11 yr after LDLT, and mean pulmonary artery pressure (mPAP) estimated by echocardiography at the time of presentation ranged from 43 to 120 mmHg. Three of the 5 patients are alive under prostaglandin I2 (PGI2) treatment. Of these, 1 is prepared for retransplantation for an intractable complications of liver allograft, while the other 2 with satisfactory grafts are being considered for lung transplantation. Even after LDLT, PH can develop with portal hypertension. Periodic echocardiography is essential for early detection and treatment of PH especially in the recipients with portal hypertension not only preoperatively but also postoperatively. Liver Transpl 12:870,875, 2006. © 2006 AASLD. [source] Nitric oxide increases dramatically in air exhaled from lung regions with occluded vesselsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2003E. Fernández-Mondéjar Background:, We observed dramatic changes in exhaled nitric oxide concentration (,NOE) during wedge measurements, and hypothesised that occlusion and redistribution of pulmonary blood flow affects NOE. Methods:, We inflated the balloon of the pulmonary artery catheter and measured NOE and central hemodynamics in closed chest anesthetised pigs (n = 11) ventilated with hyperoxic gas (fraction of inspired oxygen [FIO2] = 0.5), before and during lung injury, and in open chest anesthetised pigs (n = 17) before and during left lower lobar (LLL) hypoxia (FIO2 0.05), and during hyperoxic (FIO2 0.8) ventilation of the other lung regions (HL). Results:, In the closed chest pigs NOE increased from 2.0 (0.9) to 3.4 (2.0) p.p.b. (P < 0.001) during wedge, and returned to 2.0 (1.0) p.p.b. when the balloon was deflated. The increase in mean pulmonary artery pressure (MPaP) during wedge was small and insignificant (P > 0.07). When the balloon was inflated in the right pulmonary artery in the open chest pigs, the perfusion of the HL decreased from 2.57 (0.58) to 2.34 (0.55) l min,1 (P < 0.001), and NOEHL increased from 2.5 (0.9) to 6.2 (3.2) p.p.b. (P < 0.001). The perfusion of the LLL increased from 0.33 (0.26) to 0.54 (0.34) l min,1 (P < 0.001), and NOELLL decreased from 1.7 (0.6) to 1.5 (0.5) p.p.b. (P < 0.001). Neither lung injury nor LLL hypoxia had any influence on ,NOE (P > 0.07) during wedge. The correlation coefficient (R2) was 0.66 between changes in regional blood flow and ,NOE, and 0.37 between changes in MPaP and ,NOE. Conclusions:, Nitric oxide concentration increases dramatically from lung regions with occluded vessels, whereas changes in MPaP have minor effects on NOE. This is an important fact to consider when comparing NOE within or between studies, and indicates a possible marker of diseases with occluded lung vessels. [source] Determinants of Mortality in Patients Undergoing Cardiac Resynchronization Therapy: Baseline Clinical, Echocardiographic, and Angioscintigraphic Evaluation Prior to ResynchronizationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2005ANTONIO DE SISTI Background: In dilated cardiomyopathy (DCM) patients (pts) with cardiac resynchronization therapy (CRT) for ventricular dyssynchrony, long-term predictors of mortality and morbidity remain poorly investigated. Method and Results: We reviewed data of 102 pts, 68 ± 10 years, NYHA Class II,IV (14 Class II, 67 Class III, 21 Class IV), who benefited from CRT (69 CRT, 33 CRT-ICD). Fifty-two patients had an ischemic DCM, 36 a previously implanted conventional PM/ICD, 29 a permanent atrial fibrillation, and 19 needed dobutamine in the month preceding implant. QRS duration was 187 ± 35 ms, left ventricular end-diastolic diameter 72 ± 10 mm, mitral regurgitation severity 1.9 ± 0.8, echographic aorto-pulmonary electromechanical delay 61.5 ± 25 ms and septo-lateral left intraventricular delay 86 ± 56 ms, pulmonary artery pressure (PAP) 43 ± 11 mmHg, angioscintigraphic left ventricular ejection fraction (EF) 20 ± 9%, and right ventricular EF 30.5 ± 14%. Over a mean follow-up of 23 ± 20 months, 26 pts died (18 heart failures (HFs), 1 arrhythmic storm, 7 noncardiac deaths). Positive univariate predictors of death from any cause were NYHA Class IV (P < 0.001), and need for dobutamine the month preceding CRT (P < 0.008), while use of ,-blocking agents (P < 0.08) and left ventricular EF (P < 0.09) were negative ones. NYHA Class IV was the only independent predictor at multivariate analysis (P < 0.01). Survival at 24 months was 85% in Class II, 80% in Class III, and 37% in Class IV (II vs III, P = ns; III vs IV, P < 0.001). When using a composite endpoint of death from any cause and unplanned rehospitalization for a major cardiovascular event, there were 48 events (14 HF deaths, 3 noncardiac deaths, 26 HF rehospitalizations, 2 paroxysmal atrial fibrillation, 2 sustained ventricular tachycardia, 1 nonfatal pulmonary embolism). Predictors of death from any cause/unplanned rehospitalization for a major cardiovascular event in the follow-up were NYHA Class IV (P < 0.001), need for dobutamine during the month preceding CRT (P < 0.002), and PAP (<0.02). NYHA Class IV was the only independent predictor at multivariate analysis (P < 0.05). Event-free proportion at 24 months was 70% in Class II, 64% in Class III, and 37% in Class IV (II vs III, P = ns; III vs IV, P < 0.01). When considering determinants of mortality only in NYHA Class IV patients, no variable was significantly correlated to mortality. Need for dobutamine during the last month preceding CRT did not add an adjunctive mortality risk. Conclusion: Baseline NYHA Class IV at implantation appears as the most important determinant of a poor clinical outcome in terms of both mortality and morbidity. No predictive criteria seem available for NYHA Class IV patients, in order to discriminate who will die after CRT and who will not. NYHA Class IV strongly influences the clinical outcome, suggesting that, in future studies planned on mortality and rehospitalization as major endpoints, baseline NYHA Class IV should be separately taken into account. [source] Postbypass pulmonary artery pressure influences respiratory system compliance after ventricular septal defect closurePEDIATRIC ANESTHESIA, Issue 4 2000Muneyuki Takeuchi MD It is reported that surgical correction of left-to-right shunt improves respiratory function in paediatric cardiac patients. However, such correction sometimes does not result in an improvement of respiratory compliance. The purpose of this study was to look for factors determining changes in respiratory system compliance (Crs) in patients who underwent closure of ventricular septal defect (VSD closure). In a prospective study, 17 children (< 10 kg) who underwent VSD closure were enrolled. They were divided into two groups, according to postbypass mean pulmonary artery pressure (mPAP). The patients were allocated to Group C if mPAP was , 18 mmHg (n=12) and to Group PH if > 18 mmHg (n=5). We compared the ratio of postoperative Crs to preoperative Crs (Cpost/Cpre) between the groups. A multiple occlusion technique was used to measure Crs. The Cpost/Cpre in group C was larger than that in group PH (1.11 ± 0.17 vs. 0.81 ± 0.12, P < 0.01). There was a correlation between postbypass mPAP and Cpost/Cpre (rs=0.49, P < 0.05), but no correlation was noted between preoperative mPAP, Qp/Qs or Rp/Rs and Cpost/Cpre. We concluded that high postbypass mPAP was associated with a perioperative decrease in Crs after VSD closure. [source] Clinical significance of reduced systemic Windkessel size in severe ventricular septal defect patientsPEDIATRICS INTERNATIONAL, Issue 3 2008Keiko Kamisaka Abstract Background: Large-shunt ventricular septal defect (VSD) infants manifest varied serious symptoms resulting from peripheral arterial constriction to compensate for increased pulmonary blood flow (Qp) and concomitantly decreased systemic blood flow (Qs). The aim of the present paper was therefore to estimate the whole arterial space proximal to arterioles as the systemic Windkessel size (WS) in these infants and compare it with aortic volume (AV) estimated angiographically. Method: Subjects were divided into three groups. Group 1a consisted of the so-called balanced-pressure VSD infants; group 1b consisted of those with normal or moderately increased pulmonary artery pressure (PAP) and highly augmented Qp; and group 2 consisted of those with a history of mucocutaneous lymph node syndrome as controls for Qp and pulmonary artery pressure. WS was computed from the Windkessel model, while the AV was calculated from the angiogram. Maximal systolic (WSs), mean (WSm), and minimum diastolic (WSd) WS were defined, computed, and compared. Result: All WS were significantly smaller in group 1a; those of group 1b were between group 1a and group 2, with Qs-dependent reduction of WS throughout all these three groups. WSs, WSm, and WSd had negative correlations with right ventricular systolic pressure/left ventricular systolic pressure in group 1a and group 1b. WSm, or the time averaged size, proved to be larger than the corresponding AV in all patients. The ratio of WSm/AV was significantly reduced in group 1a compared to group 1b and group 2, indicating that systemic arterial Windkessel space in severe VSD infants is significantly small, especially so in terms of space distal to aortic valve and proximal to arterioles. Conclusion: In severe VSD infants the whole systemic arterial space proximal to arterioles (WS) is reduced in size according to severity. [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] Tonsil size as a predictor of cardiac complications in children with sleep-disordered breathing,THE LARYNGOSCOPE, Issue 6 2010Eduardo Homrich Granzotto MD Abstract Objectives/Hypothesis: The primary objective was to evaluate the association of palatine (T/P) tonsil size determined by radiography with pulmonary artery pressure (PAP) measured by Doppler echocardiography in children with surgical indication for adenotonsillar hypertrophy. The secondary objective was to evaluate if tonsil size could help to identify children at higher risk of pulmonary artery hypertension (PAH). Study Design: Cross-sectional study. Methods: The study was conducted with a consecutive sample of children with indication of adenotonsillectomy for sleep-disordered breathing. T/P was measured by lateral neck radiography, PAP by echodopplercardiography, and symptoms and quality of life by the Obstructive Sleep Apnea (OSA)-18 questionnaire. T/P was plotted in a receiver operating characteristic (ROC) curve to determine the best cut-off point to identify children with PAH. Results: A total of 45 children participated in the study. The mean age was 72.0 ± 32.3 months, and six (13%) patients had PAH. Correlation between systolic PAP and T/P was strong (r = 0.624; P < .0001). T/P was significantly higher in patients with PAH (P < .001). OSA-18 score did not significantly correlate with the variables. The cut-off point identified in the ROC was 0.66, which was the minimum T/P where sensitivity was still 100%. Mean systolic pulmonary artery pressure in children with T/P >0.66 was significantly higher than in those with T/P <0.66 (P < .001). Conclusions: T/P showed a good correlation with PAP in children with adenotonsillar hypertrophy and surgical indication for sleep-disordered breathing. Children with T/P >0.66 can be at greater risk for cardiac complications and should be submitted to complementary studies with echodopplercardiography or given preference for surgery. [source] Twenty-Year Experience With Heart Transplantation for Infants and Children With Restrictive Cardiomyopathy: 1986,2006AMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2008A. J. Bograd Idiopathic restrictive cardiomyopathy (RCM) is a rare cardiomyopathy in children notable for severe diastolic dysfunction and progressive elevation of pulmonary vascular resistance (PVR). Traditionally, those with pulmonary vascular resistance indices (PVRI) >6 W.U. × m2 have been precluded from heart transplantation (HTX). The clinical course of all patients transplanted for RCM between 1986 and 2006 were reviewed. Preoperative, intraoperative and postoperative variables were evaluated. A total of 23 patients underwent HTX for RCM, with a mean age of 8.8 ± 5.6 years and a mean time from listing to HTX of 43 ± 60 days. Preoperative and postoperative (114 ± 40 days) PVRI were 5.9 ± 4.4 and 2.9 ± 1.5 W.U. × m2, respectively. At time of most recent follow-up (mean = 5.7 ± 4.6 years), the mean PVRI was 2.0 ± 1.0 W.U. × m2. Increasing preoperative mean pulmonary artery pressure (PA) pressure (p = 0.04) and PVRI > 6 W.U. × m2 (,2= 7.4, p < 0.01) were associated with the requirement of ECMO postoperatively. Neither PVRI nor mean PA pressure was associated with posttransplant mortality; 30-day and 1-year actuarial survivals were 96% and 86%, respectively. Five of the seven patients with preoperative PVRI > 6 W.U. × m2 survived the first postoperative year. We report excellent survival for patients undergoing HTX for RCM despite the high proportion of high-risk patients. [source] The three-year incidence of pulmonary arterial hypertension associated with systemic sclerosis in a multicenter nationwide longitudinal study in FranceARTHRITIS & RHEUMATISM, Issue 6 2009Eric Hachulla Objective An algorithm for the detection of pulmonary arterial hypertension (PAH), based on the presence of dyspnea and the findings of Doppler echocardiographic evaluation of the velocity of tricuspid regurgitation (VTR) and right-sided heart catheterization (RHC), which was applied in a large multicenter systemic sclerosis (SSc) population, estimated the prevalence of PAH to be 7.85%. The aim of this observational study was to investigate the incidence of PAH and pulmonary hypertension (PH) during a 3-year followup of patients from the same cohort (the ItinérAIR-Sclérodermie Study). Methods Patients with SSc and without evidence of PAH underwent evaluation for dyspnea and VTR at study entry and during subsequent visits. Patients in whom PAH was suspected because of a VTR of 2.8,3.0 meters/second and unexplained dyspnea or a VTR of >3.0 meters/second underwent RHC to confirm the diagnosis. Results A total of 384 patients were followed up for a mean ± SD of 41.03 ± 5.66 months (median 40.92 months). At baseline, 86.7% of the patients were women, and the mean ± SD age of the patients was 53.1 ± 12.0 years. The mean ± SD duration of SSc at study entry was 8.7 ± 7.6 years. After RHC, PAH was diagnosed in 8 patients, postcapillary PH in 8 patients, and PH associated with severe pulmonary fibrosis in 2 patients. The incidence of PAH was estimated to be 0.61 cases per 100 patient-years. Two patients who exhibited a mean pulmonary artery pressure of 20,25 mm Hg at baseline subsequently developed PAH. Conclusion The estimated incidence of PAH among patients with SSc was 0.61 cases per 100 patient-years. The high incidence of postcapillary PH highlights the value of RHC in investigating suspected PAH. [source] Cardiac involvement in systemic sclerosis assessed by tissue-doppler echocardiography during routine care: A controlled study of 100 consecutive patientsARTHRITIS & RHEUMATISM, Issue 6 2008Christophe Meune Objective To assess the prevalence of primary cardiac complications in a large population of patients with systemic sclerosis (SSc), using recently developed echocardiographic techniques. Methods We prospectively studied 100 consecutive patients (mean ± SD age 54 ± 14 years; 86 women) presenting with SSc without pulmonary arterial hypertension or clinical manifestations of heart failure. All patients underwent standard echocardiography, along with measurements of longitudinal velocities by tissue Doppler imaging (TDI) to assess left ventricular (LV) and right ventricular (RV) contractility and LV diastolic function. Results were compared with those in 26 age- and sex-matched healthy controls. Results Patients with SSc had a wider mean left atrial diameter and impaired relaxation compared with the controls. A trend was observed toward a smaller LV ejection fraction (EF) in the patients (mean ± SD 64.9 ± 0.6%) than in the controls (67.2 ± 0.7%), as well as higher pulmonary artery pressure (mean ± SD 33.3 ± 0.6 mm Hg versus 30.8 ± 1.0 mm Hg). LVEF was <55% in 7 patients versus none of the controls. Peak systolic mitral annular velocity as measured by TDI was <7.5 cm/second in 14 patients versus none of the controls (P = 0.040). Mitral annulus early diastolic velocity was <10 cm/second in 30 patients versus 2 of the controls (P = 0.022). Fifteen patients and none of the controls had reduced peak systolic tricuspid annular velocity (P = 0.039). The TDI results correlated with each other, but not with lung abnormalities or other disease characteristics. Conclusion Depression of LV and RV systolic and LV diastolic function is common in patients with SSc and is due to primary myocardial involvement. Considering the major contributions of TDI, the addition of this simple technique to standard measurements may improve the detection of heart involvement in patients with SSc. [source] High N-terminal pro,brain natriuretic peptide levels and low diffusing capacity for carbon monoxide as independent predictors of the occurrence of precapillary pulmonary arterial hypertension in patients with systemic sclerosisARTHRITIS & RHEUMATISM, Issue 1 2008Y. Allanore Objective To evaluate predictors of pulmonary arterial hypertension (PAH) in a prospective cohort of patients with systemic sclerosis (SSc). Methods Routine clinical assessments as well as measurements of the diffusing capacity for carbon monoxide/alveolar volume (DLCO/VA) ratio and N-terminal pro,brain natriuretic peptide (NT-proBNP) level were performed in a prospective cohort of 101 SSc patients who did not have PAH or severe comorbidities. After a planned 36-month followup, we evaluated the predictive value of these parameters for the development of precapillary PAH, as demonstrated by cardiac catheterization, disease progression, and death. Criteria for cardiac catheterization were a systolic pulmonary artery pressure (PAP) of >40 mm Hg on echocardiography, a DLCO value of <50% without pulmonary fibrosis, and unexplained dyspnea. Results Eight patients developed PAH, 29 had disease progression, and 10 died during a median followup of 29 months. Kaplan-Meier analysis identified the following baseline parameters as being predictors of PAH: DLCO/VA ratio <70% or <60% (P < 0.01 for each comparison), elevated plasma NT-proBNP level (>97th percentile of normal; P = 0.005), echocardiographically estimated systolic PAP >40 mm Hg (P = 0.08), and erythrocyte sedimentation rate >28 mm/hour (P = 0.015). In multivariate analyses, an elevated baseline NT-proBNP level (hazard ratio [HR] 9.97 [95% confidence interval (95% CI) 1.69,62.42]) and a DLCO/VA ratio <60% (HR 36.66 [95% CI 3.45,387.6]) were predictors of the occurrence of PAH during followup. An increased NT-proBNP level together with a decreased DLCO/VA ratio of <70% was highly predictive of the occurrence of PAH during followup (HR 47.20 [95% CI 4.90,450.33]). Conclusion This prospective study identified a decreased DLCO/VA ratio and an increased NT-proBNP as predictors of PAH in SSc. Use of these markers should result in improved PAH risk stratification and allow earlier initiation of therapy. [source] N-terminal pro,brain natriuretic peptide as a diagnostic marker of early pulmonary artery hypertension in patients with systemic sclerosis and effects of calcium-channel blockersARTHRITIS & RHEUMATISM, Issue 12 2003Y. Allanore Objective To evaluate N-terminal pro,brain natriuretic peptide (NT-proBNP) as a marker of early pulmonary artery hypertension (PAH) and to study changes in the levels of this marker following treatment with dihydropyridine-type calcium-channel blocker (DTCCB) in patients with systemic sclerosis (SSc). Methods We evaluated 40 consecutive SSc patients who had been hospitalized for followup care (mean ± SD age 56 ± 11 years and mean ± SD duration of cutaneous disease 9 ± 9 years; 27 with limited cutaneous and 13 with diffuse cutaneous disease) but who had no clinical symptoms of heart failure and had a normal left ventricular ejection fraction. At baseline, 10 patients had PAH, defined as a systolic pulmonary artery pressure (sPAP) >40 mm Hg, as measured by echocardiography. Levels of NT-proBNP were determined at baseline (after discontinuation of DTCCB treatment for 72 hours), after taking 3 doses of DTCCB following treatment reinitiation (assessment 1), and after 6,9 months of continuous DTCCB treatment (assessment 2) in the 20 patients who attended regular appointments (including the 10 patients with PAH at baseline). Results At baseline, 13 patients had high NT-proBNP values for their ages. High NT-proBNP levels identified patients with PAH with a sensitivity of 90%, a specificity of 90.3%, a positive predictive value of 69.2%, and a negative predictive value of 96%. The NT-proBNP level correlated with the sPAP (r = 0.44; P = 0.006). By assessment 1, the number of patients with PAH and high levels of NT-proBNP had decreased from 9 of 10 to 2 of 10 (P = 0.02). This decrease was partially sustained at assessment 2 (4 of 10 patients; P = 0.06). Conclusion NT-proBNP is a useful biologic marker that can be used to diagnose early PAH in SSc patients without clinical heart failure. Measurement of NT-proBNP may be valuable for the evaluation of treatment with DTCCB and vasodilators in patients with PAH. [source] Coronary Hemodynamics and Myocardial Oxygen Consumption During Support With Rotary Blood PumpsARTIFICIAL ORGANS, Issue 1 2009Peter Voitl Abstract Mechanical support offered by rotary pumps is increasingly used to assist the failing heart, although several questions concerning physiology remain. In this study, we sought to evaluate the effect of left-ventricular assist device (VAD) therapy on coronary hemodynamics, myocardial oxygen consumption, and pulmonary blood flow in sheep. We performed an acute experiment in 10 sheep to obtain invasively measured coronary perfusion data, as well as pressure and flow conditions under cardiovascular assistance. A DeBakey VAD (MicroMed Cardiovascular, Inc., Houston, TX, USA) was implanted, and systemic and coronary hemodynamic measurements were performed at defined baseline conditions and at five levels of assistance. Data were measured when the pump was clamped, as well as under minimum, maximum, and moderate levels of assistance, and in a pump-off condition where backflow occurs. Coronary flow at the different levels of support showed no significant impact of pump activity. The change from baseline ranged from ,10.8% to +4.6% (not significant [n.s.]). In the pulmonary artery, we observed a consistent increase in flow up to +4.5% (n.s.) and a decrease in the pulmonary artery pressure down to ,14.4% (P = 0.004). Myocardial oxygen consumption fell with increasing pump support down to ,34.6% (P = 0.008). Left-ventricular pressure fell about 52.2% (P = 0.016) as support was increased. These results show that blood flow in the coronary arteries is not affected by flow changes imposed by rotary blood pumps. An undiminished coronary perfusion at falling oxygen consumption might contribute to cardiac recovery. [source] Implantation of One Piece Biventricular Assist Device by Left Thoracotomy in an Ovine ModelARTIFICIAL ORGANS, Issue 9 2000Won Gon Kim Abstract: In this report, we describe an operative procedure for our implantable 1 piece biventricular assist device (BiVAD) based on a moving actuator mechanism, using an ovine model. Our implantable BiVAD is a volumetric coupled 1 piece unit including right and left blood sacs and an actuator assembly based on the moving actuator mechanism. The BiVAD was controlled by fixed rate control with 75 bpm for the most part. Both the left and the right full ejection modes with the maximum stroke angle were selected to minimize blood stasis in the blood sacs because of low assist flow condition. Three Corriedale sheep were used for the device implantation by a left thoracotomy incision. Cannulation was successfully performed in all cases. Although exposability of the right atrial appendage varied from animal to animal, the insertion of the cannula was easily performed. The cannulas were connected to the pump-actuator assembly in the preperitoneal pocket. All 3 animals survived the experimental procedure. During implantation of the device, in the 1 month survival animal, pump flow was maintained between 2.0 L/min and 2.5 L/min, mean aortic pressure was 90,110 mm Hg, and mean pulmonary artery pressure was 20,30 mm Hg. The left and right atrial pressure were maintained between 0 and 5 mm Hg. In conclusion, this ovine model for implantation of the 1 piece BiVAD can be an effective alternative for testing in vivo biocompatibility of the device although it needs more consideration for anatomical fittability for future human application. [source] Sildenafil Improves the Beneficial Haemodynamic Effects of Intravenous Nitrite Infusion during Acute Pulmonary EmbolismBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2008Carlos A. Dias-Junior While previous studies have shown that sildenafil (an inhibitor of cGMP-specific phosphodiesterase type 5) or nitrite (a storage molecule for nitric oxide) produces beneficial effects during acute pulmonary embolism, no previous study has examined whether the combination of these drugs can produce additive effects. Here, we expand previous findings and examine whether sildenafil enhances the beneficial haemodynamic effects produced by a low-dose infusion of nitrite in a dog model of acute pulmonary embolism. Haemodynamic and arterial blood gas evaluations were performed in non-embolized dogs treated with saline (n = 4), and in embolized dogs (intravenous injections of microspheres) that received nitrite (6.75 µmol/kg intravenously over 15 min. followed by 0.28 µmol/kg/min.) and sildenafil (0.25 mg/kg over 30 min.; n = 8), or nitrite followed by saline (n = 8), or saline followed by sildenafil (n = 7), or only saline (n = 8). Plasma thiobarbituric acid-reactive substances (TBARS) concentrations were determined using a fluorometric method. Acute pulmonary embolism increased pulmonary artery pressure by ,24 mmHg. While the infusion of nitrite or sildenafil infusions reversed this increase by ,42% (both P < 0.05), the combined infusion of both drugs reversed this increase by ,58% (P < 0.05). Similar effects were seen on the pulmonary vascular resistance index. Nitrite or sildenafil alone produced no significant hypotension. However, the combined infusion of both drugs caused transient hypotension (P < 0.05). Both dugs, either alone or combined, blunted the increase in TBARS concentrations caused by acute pulmonary embolism (all P < 0.05). These results suggest that sildenafil improves the beneficial haemodynamic effects of nitrite during acute pulmonary embolism. [source] Baicalin attenuates air embolism-induced acute lung injury in rat isolated lungsBRITISH JOURNAL OF PHARMACOLOGY, Issue 2 2009Min-Hui Li Background and purpose:, Baicalin has been reported to have anti-inflammatory effects and protect against various tissue injuries. However, the effect of baicalin on air embolism-induced acute lung injury has not been tested yet. Experimental approach:, Acute lung injury was induced by infusion of air at a rate of 0.25 mL·min,1 for 1 min into the pulmonary artery of rat isolated lungs. At the end of the experiment, samples were collected for assessment of lung injury, biochemical analysis and histology. Different doses of baicalin (1, 2 and 4 mg·kg,1) were given into the perfusate before air infusion. Key results:, Air embolism elicited a significant increase in microvascular permeability (Kf), lung weight gain, wet/dry weight ratio, pulmonary artery pressure and protein concentration in the bronchoalveolar lavage fluid. Levels of the cytokines, tumour necrosis factor , and cytokine-induced neutrophil chemoattractant-1 in perfusate, and malondialdehyde levels and myeloperoxidase activities in lung tissue were also significantly increased. In addition, histological examination showed increased neutrophil infiltration in lung tissues. Furthermore, nuclear factor-,B activity and degradation of I,B-, were significantly increased in lungs. Pretreatment of the lungs with baicalin (4 mg·kg,1) showed a statistically significant difference in all of the assessed parameters, except for alteration in the pulmonary artery pressure. Conclusions and implications:, Our study suggests that baicalin attenuated air embolism-induced acute lung injury and may be considered a useful adjunct drug therapy in this clinical condition. [source] The Extracellular Signal-Regulated Kinase Is Involved in the Effects of Sildenafil on Pulmonary Vascular RemodelingCARDIOVASCULAR THERAPEUTICS, Issue 1 2010Zhen Zeng Pulmonary hypertension is a group of diseases comprising vascular constriction and obstructive changes of the pulmonary vasculature. Phosphodiesterase type 5 inhibitors, for example, sildenafil, can alleviate vascular remodeling in the monocrotaline pulmonary hypertension model in rats. We investigate the mechanisms of sildenafil on the pulmonary vascular remodeling of pulmonary hypertension induced by monocrotaline (MCT) in rats. Thirty Sprague-Dawley rats (weighing 200,220 g) were administered with MCT abdominal cavity injection or equivalent volume of normal saline (NS) (which were treated as C group n = 10) to induce pulmonary hypertension model. Fourteen days later, 20 MCT treated rats were randomly fed with sildenafil (25mg/kg/day) or placebo as S, P group (10 rats for each group), respectively. Another 6 weeks later, mean pulmonary artery pressure (mPAP), index of right ventricular hypertrophy (RV/LV+S) of all animals were measured under general anesthesia. Pulmonary tissue was collected to investigate pathological features of pulmonary arteries and to measure protein expression of ERK1/ERK2 and MKP1. After 6 weeks, there were significant elevated mPAP and RV/LV+S in both P and S groups. The ratio of wall thickness to vessel diameter in pulmonary arteries with diameters <200 ,m were increased in both P and S groups. But the ratio of wall thickness to vessel diameter was smaller in S group than that in P group. The phosphorylation level of ERK1/ERK2 were elevated in both P and S groups, but the level of phosphorlation ERK1/ERK2 were lower in S group than that in P group. Intriguingly, the expression level of MKP1 was significantly increased in both S and P groups, while it was higher in S group than that in P group. The Sildenafil can decrease mPAP and inhibit the progress of pulmonary vascular remodeling in pulmonary hypertension rats. The ERK-MAP kinase signaling pathway might play a role during this process. [source] | |||||||||||||||||||||||||||||||