Estimation Of Right Ventricular Function Research Articles

Prospective validation of right ventricular role in primary graft dysfunction after lung transplantation.

Primary graft dysfunction is a significant cause of lung transplant morbidity and mortality, but its underlying mechanisms are not completely understood. The aims of the present study were: 1) to confirm that right ventricular function is a risk factor for severe primary graft dysfunction; and 2) to propose a clinical model for predicting the development of severe primary graft dysfunction.A prospective cohort study was performed over 14 months. The primary outcome was development of primary graft dysfunction grade 3. An echocardiogram was performed immediately before transplantation, measuring conventional and speckle-tracking parameters. Pulmonary artery catheter data were also measured. A classification and regression tree was made to identify prognostic models for the development of severe graft dysfunction.70 lung transplant recipients were included. Patients who developed severe primary graft dysfunction had better right ventricular function, as estimated by cardiac index (3.5±0.8 versus 2.6±0.7 L·min-1·m-2, p<0.01) and basal longitudinal strain (-25.7±7.3% versus -19.5±6.6%, p<0.01). Regression tree analysis provided an algorithm based on the combined use of three variables (basal longitudinal strain, pulmonary fibrosis disease and ischaemia time), allowing accurate preoperative discrimination of three distinct subgroups with low (11-20%), intermediate (54%) and high (75%) risk of severe primary graft dysfunction (area under the receiver operating characteristic curve 0.81).Better right ventricular function is a risk factor for the development of severe primary graft dysfunction. Preoperative estimation of right ventricular function could allow early identification of recipients at increased risk, who would benefit the most from careful perioperative management in order to limit pulmonary overflow.

Non-invasive Estimation of Right Ventricular Function: Do the Cut-offs Need to be Redefined?

Non-invasive Estimation of Right Ventricular Function: Do the Cut-offs Need to be Redefined?

Right Isovolumic Contraction Velocity Predicts Survival in Pulmonary Hypertension

Right ventricular function is a strong determinant of prognosis in severe pulmonary hypertension. The aim of this study was to evaluate the prognostic value of estimates of right ventricular function obtained by echocardiography and Doppler tissue imaging and of functional class and 6-min walk distance (6MWD) in 142 patients with either pulmonary arterial hypertension (n= 104) or chronic thromboembolic pulmonary hypertension (n= 38). Echocardiography was prospectively performed, and demographics, medications, associated medical conditions, New York Heart Association class, and 6MWD at inclusion in addition to vital status, transplantation, and hospital admission related to pulmonary hypertension at follow-up were then collected by review of the medical records. Variables associated with overall survival by univariate analysis were 6MWD (P= .009), functional class (P= .024), tricuspid annular plane systolic excursion (P= .03) and isovolumic peak velocity at the tricuspid annulus (IVCv) (P= .003). On multivariate analysis, IVCv (P= .015) and 6MWD (P= .016) were the only independent predictors of survival. Kaplan-Meier estimates of survival at 1 year were 95% in patients with IVCv > 9 cm/sec and 80% in those with IVCv ≤ 9 cm/sec (P= .002). Intraobserver and interobserver variability of IVCv measurement were 5% and 9%, respectively. Measurement of right ventricular function by Doppler tissue imaging, an easy, noninvasive, and reproducible method, is an independent predictor of clinical outcomes in patients with severe pulmonary hypertension.

Semiautomatic quantification of left and right ventricular function in cardiac magnetic resonance imaging: A preliminary study

ObjectivesThe aim of this study was to compare a semiautomatic segmentation method to quantify the function of both ventricles in magnetic resonance imaging (MRI) with the manual tracing method. Material and methodsWe examined 17 patients with diverse cardiovascular diseases on a 1.5 Tesla MRI unit (Magnetom Symphony Quantum; Siemens Medical Systems, Erlangen, Germany) using the following parameters: maximum gradient, 30 mT/m; and slew rate, 125 T/m/s. In all studies, we acquired images in cine mode in the short axis (SSFP, 6mm slice thickness, from the base to the ventricular apex) with breath holding. To reduce the user interaction, we used only one image per patient to initiate the semiautomatic method. The semiautomatic method was based on a specifically designed algorithm of regional growth and border detection. We quantified the end-diastolic volume (EDV), end-systolic volume (ESV), and the ejection fraction (EF) for both ventricles in all patients. ResultsNo significant differences between the two segmentation techniques were found in the quantification of either ventricle (p>0.05). The difference in the volumes, although nearly significant, are clinically irrelevant. The correlation for the estimation of left ventricular function was excellent (r>0.9), and the correlation for the estimation of right ventricular function was good (r>0.7). ConclusionsOur semiautomatic segmentation method enables the function of both ventricles to be quantified as accurately as the conventional method.

Cuantificación semiautomática de la función ventricular izquierda y derecha en resonancia magnética cardíaca. Estudio preliminar

Objectives The aim of this study was to compare a semiautomatic segmentation method to quantify the function of both ventricles in magnetic resonance imaging (MRI) with the manual tracing method. Material and methods We examined 17 patients with diverse cardiovascular diseases on a 1.5 Tesla MRI unit (Magnetom Symphony Quantum; Siemens Medical Systems, Erlangen, Germany) using the following parameters: maximum gradient, 30 mT/m; and slew rate, 125 T/m/s. In all studies, we acquired images in cine mode in the short axis (SSFP, 6 mm slice thickness, from the base to the ventricular apex) with breath holding. To reduce the user interaction, we used only one image per patient to initiate the semiautomatic method. The semiautomatic method was based on a specifically designed algorithm of regional growth and border detection. We quantified the end-diastolic volume (EDV), end-systolic volume (ESV), and the ejection fraction (EF) for both ventricles in all patients. Results No significant differences between the two segmentation techniques were found in the quantification of either ventricle (p > 0.05). The difference in the volumes, although nearly significant, are clinically irrelevant. The correlation for the estimation of left ventricular function was excellent (r > 0.9), and the correlation for the estimation of right ventricular function was good (r > 0.7). Conclusions Our semiautomatic segmentation method enables the function of both ventricles to be quantified as accurately as the conventional method.

Tissue Doppler Global Function Index and Strain Imaging Estimation of Right Ventricular Function in Type 2 Diabetic Patients

Background: Subclinical right ventricular (RV) diastolic dysfunction has been reported to be prevalent in diabetic subjects, but effect on systolic function is not clear and requiring investigation. Strain imaging has been suggested as a useful tool for the evaluation of myocardial function. A global function index (GFI) derived from tissue Doppler imaging (TDI) has been proposed to improve the diagnosis of hypertrophic cardiomyopathy. We aimed to evaluate the usefulness of this index and strain imaging in RV assessment.

Étude de la fonction ventriculaire droite par 2D speckle imaging et échographie tridimensionnelle. Comparaison à l’IRM myocardique

Purpose The echocardiographic assessment of right ventricular (RV) function requires many different parameters. We studied and compared with magnetic resonance imaging (MRI) two markers of RV function derived from new imaging tools: 2D speckle imaging (2DSI) and three dimensional echography. Methods and results Thirty-two patients (19 with RV ejection fraction [RVEF] ≤ 45%) underwent both complete echocardiography – including standard parameters of RV function (fractional area change [FAC], Tei index, systolic velocity of tricuspid annulus by DTI), 3D full-volume acquisition on RV – and MRI for the evaluation of RV volumes and RVEF. 2DSI was applied to high frame rate cine loops centred on the RV free wall with measurement of peak systolic strain (%) in the basal, median and apical segments of this wall. Strain, especially in RV median and apical segments, is reduced in patients with RVEF less or equal to 45% (median strain: −16,39 ± 5,27 vs. −24,74 ± 8,00 [ p = 0,002]; apical strain −13,01 ± 6,84 vs. 22,53 ± 11,32 [ p = 0,03]) with a very good correlation with RVEF ( r = −0,717, p = 0,0001) but also with the usual echographic parameters of RV function, (FAC: r = 0,019; Tei: r = 0,01; peak systolic velocity: r = 0,002). The 3D RVEF is also but poorly correlated with MRI RVEF, ( r = 0,447, p = 0,017). Furthermore, 3D significantly underestimated RV volumes. By multivariate analysis, apical strain ( p = 0,004) and FAC ( p = 0,029) were predictive of a decreased RVEF. Conclusion Apical strain as measured from 2DSI seems a promising parameter in the estimation of RV function. 3D estimation of RVEF is more disappointing because of an important underestimation of RV volumes.

2057 Quantitative estimation of right ventricular function obtained from images acquired in oblique sagittal orientation is accurate and easier compared to that obtained by the left ventricular short axis and oblique transverse orientations

2057 Quantitative estimation of right ventricular function obtained from images acquired in oblique sagittal orientation is accurate and easier compared to that obtained by the left ventricular short axis and oblique transverse orientations

Usefulness of Dobutamine Stress Echocardiography with Tissue Doppler Imaging for the Evaluation and Follow-Up of Patients with Repaired Tetralogy of Fallot

The longstanding pulmonary regurgitation in patients with repaired tetralogy of Fallot (RTOF) results in right ventricular (RV) failure. The estimation of RV function and reserve in these patients is of great importance, especially for the determination of the proper timing of pulmonary valve replacement. Tissue Doppler imaging (TDI) of the tricuspid annulus has been proved a valuable tool in the evaluation of these patients. Dobutamine stress echocardiography (DSE) in low doses detects the contractility reserve of cardiac myocytes. The aim of our study was to estimate RV reserve in patients with RTOF with the use of DSE and TDI and to examine whether this is related to baseline TDI indices of the tricuspid annulus. We studied 21 patients with RTOF and 21 age- and gender-matched controls with TDI Doppler at the tricuspid annulus during DSE. TDI measurements were made at baseline and at infusion rates of 10 and 20 microg x kg x min. Patients with RTOF had lower values of TDI indices at baseline and during dobutamine infusion and smaller dobutamine-induced increase of Sa (DeltaSa) (3.8 +/- 1.2 vs. 10.8 +/- 3.6 cm/sec, P < .001) and Aa (3.5 +/- 2.2 vs. 10.0 +/- 3.2 cm/sec, P < .001). A value of DeltaSa < or = 6 cm/sec clearly discriminated patients from controls and could be predicted by values of Sa < 11.5 cm/sec with sensitivity of 95% and specificity of 100%. In patients with RTOF, impaired RV contractile reserve can be documented with TDI of tricuspid annular motion during DSE and is predicted by TDI indices at rest. Its serial estimation may contribute to optimal timing of reoperation.

Right ventricular ejection fraction measured by first-pass intravenous krypton-81m: Reproducibility and comparison with technetium-99m

Study of the effects of various diseases and therapeutic manipulation of pulmonary vascular resistance on the right ventricle has been restricted by methodologic limitations. The radioactive gas in solution, krypton-81m was used to study the right ventricle and the technique was compared with a technetium-99m method. In 22 subjects, first-pass krypton-81m right ventricular ejection fraction, acquired both in list mode and electrocardiogramgated frame mode, correlated well (r = 0.81 and 0.86, respectively, p < 0.01) with that determined by technetium-99m first-pass studies over a broad range of ventricular function. The reproducibility of the technique was excellent (r = 0.84 and 0.95 for each acquisition mode, respectively). Krypton-81m first-pass studies provide accurate and reproducible estimates of right ventricular function. Use of krypton allows multiple measurements, with or without perturbations, over a short period of time.