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RV Volumes (rv + volume)
Selected AbstractsIncreased plasma levels of natriuretic peptide type B and A in children with congenital heart defects with left compared with right ventricular volume overload or pressure overloadCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 5 2005Daniel Holmgren Summary Aim:, Natriuretic peptide levels B (BNP) and A (ANP) have been described in children with congenital heart defects (CHD) with pressure and volume overload. However, the impact of ventricular morphology per se on natriuretic peptide levels has not been reported. The aim of the present study was to evaluate plasma BNP and ANP in children with CHD with left or right ventricular volume or pressure overload. Methods and results:, Plasma BNP and ANP were analysed in 61 children, median age 3·1 (0·3,16·2) years. Haemodynamic load was evaluated by echo-Doppler and/or catheterization measurements and classified as: pressure overload of the right (RV pressure) or left (LV pressure) ventricle, or volume overload of the right (RV volume) or left (LV volume) ventricle, of a sufficient degree to indicate surgery/catheter intervention. Twenty-three children, with a median age of 1·1 (0·1,8·3) years, without heart disease, served as controls for the natriuretic peptide measurements. Children in the LV volume group had significantly higher BNP and ANP values, 55·4 ng l,1 (10·7,352) and 164 (31·8,346), than children in the RV volume, 15·6 (0·0,105·1) and 57·2 (11·3,234·1), LV pressure, 6·8 (0·7,170) and 40·8 (12·6,210), and RV pressure, 18·0 (5·0,29·1) and 69·3 (8·7,182), groups respectively (P<0·0001). The values in the LV pressure group were close to the values in the Control group, 4·7 (0·0,17·7) and 32·9 (11·7,212·1), respectively (P = 0·051 and P = 0·378, respectively). Conclusions:, Plasma concentrations of BNP and ANP were higher in children with CHD with left ventricular volume overload compared with right ventricular volume overload or pressure overload. [source] Right Ventricular Function Assessment: Comparison of Geometric and Visual Method to Short-Axis Slice Summation MethodECHOCARDIOGRAPHY, Issue 10 2007Daniel Drake M.D. Background: Short-axis summation (SAS) method applied for right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) measurement with cardiac MRI is time consuming and cumbersome to use. A simplified RVEF measurement is desirable. We compare two such methods, a simplified ellipsoid geometric method (GM) and visual estimate, to the SAS method to determine their accuracy and reproducibility. Methods: Forty patients undergoing cine cardiac MRI scan were enrolled. The images acquired were analyzed by the SAS method, the GM (area and length measurement from two orthogonal planes) and visual estimate. RVEF was calculated using all three methods and RV volumes using the SAS and GM. Bland,Altman analysis was applied to test the agreement between the various measurements. Results: Mean RVEF was 49 ± 12% measured by SAS method, 54 ± 12% by the GM, and 49 ± 11% by visual estimate. There were similar bias and limits of agreement between the visual estimate and the GM compared to SAS. The interobserver variability showed a bias close to zero with limits of agreement within ±10% absolute increments of RVEF in 35 of the patients. The RV end-diastolic volume by GM showed wider limits of agreement. The RV end-systolic volume by GM was underestimated by around 10 ml compared to SAS. Conclusion: Both the visual estimate and the GM had similar bias and limits of agreement when compared to SAS. Though the end-systolic measurement is somewhat underestimated, the geometric method may be useful for serial volume measurements. [source] Two-Dimensional Assessment of Right Ventricular Function: An Echocardiographic,MRI Correlative StudyECHOCARDIOGRAPHY, Issue 5 2007Nagesh S. Anavekar M.D. Background: While echocardiography is used most frequently to assess right ventricular (RV) function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Hence, quantitative estimation of RV function has proven difficult in clinical practice. Objective: We sought to determine which commonly used echocardiographic measures of RV function were most accurate in comparison with an MRI-derived estimate of RVEF. Methods: We analyzed RV function in 36 patients who had cardiac MRI studies and echocardiograms within a 24 hour period. 2D parameters of RV function,right ventricular fractional area change (RVFAC), tricuspid annular motion (TAM), and transverse fractional shortening (TFS) were obtained from the four-chamber view. RV volumes and EFs were derived from volumetric reconstruction based on endocardial tracing of the RV chamber from the short axis images. Echocardiographic assessment of RV function was correlated with MRI findings. Results: RVFAC measured by echocardiography correlated best with MRI-derived RVEF (r = 0.80, P < 0.001). Neither TAM (r = 0.17; P = 0.30) nor TFC (r = 0.12; p< 0.38) were significantly correlated with RVEF. Conclusions: RVFAC is the best of commonly utilized echocardiographic 2D measure of RV function and correlated best with MRI-derived RV ejection fraction. Condensed Abstract: While echocardiography is used most frequently to assess RV function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Using cardiac MRI, RV fractional area change (RVFAC), determined either by MRI or echocardiography, was found to correlate best with MRI-derived RVEF. [source] Phenotyping the Right Ventricle in Patients with Pulmonary HypertensionCLINICAL AND TRANSLATIONAL SCIENCE, Issue 4 2009M.S., Marc A. Simon M.D. Abstract Right ventricular (RV) failure is associated with poor outcomes in pulmonary hypertension (PH). We sought to phenotype the RV in PH patients with compensated and decompensated RV function by quantifying regional and global RV structural and functional changes. Twenty-two patients (age 51 ± 11, 14 females, mean pulmonary artery (PA) pressure range 13,79 mmHg) underwent right heart catheterization, echocardiography, and ECG-gated multislice computed tomography of the chest. Patients were divided into three groups: Normal, PH with hemodynamically compensated, and decompensated RV function (PH-C and PH-D, respectively). RV wall thickness (WT) was measured at end-diastole (ED) and end-systole (ES) in three regions: infundibulum, lateral free wall, and inferior free wall. Globally, RV volumes progressively increased from Normal to PH-C to PH-D and RV ejection fraction decreased. Regionally, WT increased and fractional wall thickening (FWT) decreased in a spatially heterogeneous manner. Infundibular wall stress was elevated and FWT was lower regardless of the status of global RV function. In PH, there are significant phenotypic abnormalities in the RV even in the absence of overt hemodynamic RV decompensation. Regional changes in RV structure and function may be early markers of patients at risk for developing RV failure. [source] Influence of right ventricular pre- and afterload on right ventricular ejection fraction and preload recruitable stroke work relationCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2001Wolfram Burger When right ventricular (RV) afterload is abnormally increased, it correlates inversely with right ventricular ejection fraction (RVEF). We tested, whether this would be different with normal afterload. Additionally, we investigated whether previous studies on the slope of RV preload recruitable stroke work (SW) relation, which used rather non-physiological measures to change RV preload, could be transferred to more physiological loading conditions. RV volumes were determined by thermodilution in 16 patients with stable coronary artery disease and normal pulmonary artery pressure (PAP) at rest. Pre- and afterload were varied by body posture, nitroglycerin (NTG) application and by exercise at different body positions. At rest, the change from recumbent to sitting position decreased PAP, cardiac index (Ci), RV diastolic and systolic volumes, and RVEF. Additionally, mean pulmonary artery pressure (MPAP) correlated positively with both RVEF and cardiac index. After correction for mathematical coupling, the RV preload recruitable SW relation was: right ventricular stroke work index (RVSWi) (103 erg m,2)= 8·1 × (RV end-diastolic volume index ,4·9), with n=96, r=0·57, P,0·001. Exercise abolished this correlation and led to an inverse correlation between RV end-systolic volume (ESV) and RVSW. In conclusion, (i) RVEF correlates positively with RV afterload when afterload varies within normal range; (ii) the slope of the RV preload recruitable SW relation, which is obtained at steady state under normal loading conditions, is substantially flatter than previously described for dynamic changes of RV preload. With increasing afterload, preload loses its determining effect on RV performance, while afterload becomes more important. This puts earlier assumptions of an afterload independent RV preload recruitable SW relation into question. [source] |