Cardiac Ventricular Volumes Research Articles

Exercise-induced cardiovascular remodelling in a large cohort of female, elite athletes: towards sex-specific CMR reference ranges

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): Amsterdam Movement Sciences (AMS); Dutch National Olympic Committee & National Sports Federation (NOC*NSF); Heart To Handle. Background Differentiating between exercise-induced cardiac remodelling (EICR) and pathology constitutes a central challenge in sports cardiology. To facilitate this differentiation, reference ranges for cardiovascular magnetic resonance imaging (CMR) are needed. However, female athletes, and especially, female elite athletes with potentially the most outspoken adaptation, are severely underrepresented. Moreover, no large studies including CMR data in female, elite athletes are currently available. Purpose To quantify EICR on CMR in a large cohort of female, elite athletes, compared with currently available reference values of the general female, and female athlete population. Methods We performed a cross-sectional CMR analysis in female elite athletes aged ≥16 years, included in the ELITE cohort. We excluded athletes with known cardiovascular disease. The primary outcome was EICR quantification as BSA indexed RV and LV end-diastolic volume (EDVi), LV wall mass (LVMi), LV remodelling index (LVMi/LVEDVi), and LV/RV ratio (LVEDi/RVEDVi). Second, we compared our parameters with reference ranges (1,2). CMR was performed according to a uniform protocol, and included cine-imaging and delayed hyperenhancement, preferentially on 1.5T. A dedicated core-lab analysed all CMRs in Circle Cardiovascular Imaging. Results We included 102 female elite athletes, 97% caucasian, mean age of 26.3 ±5.0, BSA 1.79 ±0.14 m2, and mean professional athlete years of 10.3 ±5. Main athlete disciplines (≥10 hours/week) were field hockey (15%), rowing (13%), road cycling (12%), and European style football (10%). Female elite athletes had marked EICR as compared with general population reference values, with higher LVEDVi (108 ±13.9 vs 69 ±12 ml/m2, p<0.05), RVEDVi (110 ±15.3 vs 76 ±14 ml/m2, p<0.05), and LVMi (49.9 ±11.2 vs 45 ±7 g/m2, p<0.05) (Figure 1). Compared with current female elite athlete references (n=33), our female elite athlete population demonstrated a markedly lower RVEDVi (118 ±17 vs 110 ±15 ml/m2), and a higher upper-limit (95th percentile) of LVMi (66 vs 72.3 g/m2) with comparable LVEDVi. LV remodelling showed a lower LVM/LVEDV ratio (0.46 ±0.08 vs 0.7 ±0.1 ml) compared to the general population, with balanced dilatation (LVEDV/RVEDV=0.98 ±0.05). In general, we observed EICR as increased cardiac volumes in 67% (n=68), increased cardiac volumes and mass in 21% (n=21) lone increase in cardiac mass in 1% (n=1), with 11% (n=11) demonstrating normal geometry (Figure 2). Conclusion EICR on CMR in female, elite athletes is mainly characterised by isolated increased volumes, with a considerable proportion (11%) demonstrating no EICR. Compared with the general population, female athletes have larger cardiac ventricular volumes and wall mass; compared with available elite athlete reference ranges comparable ventricular volumes, but a larger spread in cardiac wall mass. Our results constitute a first step towards sex-specific CMR reference ranges for female athletes.

Estimated Ventricular Size, Asthma Severity, and Exacerbations: The Severe Asthma Research Program III Cohort

Relative enlargement of the pulmonary artery (PA) on chest CT imaging is associated with respiratory exacerbations in patients with COPD or cystic fibrosis. We sought to determine whether similar findings were present in patients with asthma and whether these findings were explained by differences in ventricular size. We measured the PA and aorta diameters in 233 individuals from the Severe Asthma Research Program III cohort. We also estimated right, left, and total epicardial cardiac ventricular volume indices (eERVVI, eELVVI, and eETVVI, respectively). Associations between the cardiac and PA measures (PA-to-aorta [PA/A] ratio, eERVVI-to-eELVVI [eRV/eLV] ratio, eERVVI, eELVVI, eETVVI) and clinical measures of asthma severity were assessed by Pearson correlation, and associations with asthma severity and exacerbation rate were evaluated by multivariable linear and zero-inflated negative binomial regression. Asthma severity was associated with smaller ventricular volumes. For example, those with severe asthma had 36.1mL/m2 smaller eETVVI than healthy control subjects (P= .003) and 14.1mL/m2 smaller eETVVI than those with mild/moderate disease (P= .011). Smaller ventricular volumes were also associated with a higher rate of asthma exacerbations, both retrospectively and prospectively. For example, those with an eETVVI less than the median had a 57%higher rate of exacerbations during follow-up than those with eETVVI greater than the median (P= .020). Neither PA/A nor eRV/eLV was associated with asthma severity or exacerbations. In patients with asthma, smaller cardiac ventricular size may be associated with more severe disease and a higher rate of asthma exacerbations. ClinicalTrials.gov; No.: NCT01761630; URL: www.clinicaltrials.gov.

Direct and simultaneous estimation of cardiac four chamber volumes by multioutput sparse regression.

Cardiac four-chamber volume estimation serves as a fundamental and crucial role in clinical quantitative analysis of whole heart functions. It is a challenging task due to the huge complexity of the four chambers including great appearance variations, huge shape deformation and interference between chambers. Direct estimation has recently emerged as an effective and convenient tool for cardiac ventricular volume estimation. However, existing direct estimation methods were specifically developed for one single ventricle, i.e., left ventricle (LV), or bi-ventricles; they can not be directly used for four chamber volume estimation due to the great combinatorial variability and highly complex anatomical interdependency of the four chambers. In this paper, we propose a new, general framework for direct and simultaneous four chamber volume estimation. We have addressed two key issues, i.e., cardiac image representation and simultaneous four chamber volume estimation, which enables accurate and efficient four-chamber volume estimation. We generate compact and discriminative image representations by supervised descriptor learning (SDL) which can remove irrelevant information and extract discriminative features. We propose direct and simultaneous four-chamber volume estimation by the multioutput sparse latent regression (MSLR), which enables jointly modeling nonlinear input-output relationships and capturing four-chamber interdependence. The proposed method is highly generalized, independent of imaging modalities, which provides a general regression framework that can be extensively used for clinical data prediction to achieve automated diagnosis. Experiments on both MR and CT images show that our method achieves high performance with a correlation coefficient of up to 0.921 with ground truth obtained manually by human experts, which is clinically significant and enables more accurate, convenient and comprehensive assessment of cardiac functions.

Multi-scale deep networks and regression forests for direct bi-ventricular volume estimation.

Direct estimation of cardiac ventricular volumes has become increasingly popular and important in cardiac function analysis due to its effectiveness and efficiency by avoiding an intermediate segmentation step. However, existing methods rely on either intensive user inputs or problematic assumptions. To realize the full capacities of direct estimation, this paper presents a general, fully learning-based framework for direct bi-ventricular volume estimation, which removes user inputs and unreliable assumptions. We formulate bi-ventricular volume estimation as a general regression framework which consists of two main full learning stages: unsupervised cardiac image representation learning by multi-scale deep networks and direct bi-ventricular volume estimation by random forests. By leveraging strengths of generative and discriminant learning, the proposed method produces high correlations of around 0.92 with ground truth by human experts for both the left and right ventricles using a leave-one-subject-out cross validation, and largely outperforms existing direct methods on a larger dataset of 100 subjects including both healthy and diseased cases with twice the number of subjects used in previous methods. More importantly, the proposed method can not only be practically used in clinical cardiac function analysis but also be easily extended to other organ volume estimation tasks.

Abstract 8425: Fetal Cardiac Ventricular Volume and Mass Derived from Spatio-Temporal Image Correlation

Background: Fetal cardiac assessment is usually performed qualitatively. Functional and longitudinal studies of abnormal fetuses would benefit from reproducible quantitative cardiac measurements. We used spatio-temporal image correlation (STIC) to measure left and right ventricular (LV, RV) volumes and masses in normal and structurally abnormal fetal hearts. Methods: 44 normal fetuses and 7 with structural heart disease (dextrocardia, DORV, d-TGA, HLHS, pulmonary stenosis PS, VSD) at gestational ages between 16 and 38 completed weeks were included. STIC volumes were acquired and analyzed in end-diastole and end-systole according to an established and validated method. Results: Measurements were possible in all fetuses. Ventricular volumes and masses increased with gestation. In fetal DORV, HLHS and PS, RV volumes were increased, in DORV and PS, RV mass was increased. In normal hearts, RV mass was 20% higher than LV mass throughout gestation, but the ejection fraction was slightly higher in the LV. Conclusions: Using STIC the human fetal heart can be studied quantitatively, taking into account the complex geometry especially related to the right ventricle.

Reliability of fetal cardiac volumetry using spatiotemporal image correlation: assessment of in‐vivo and in‐vitro measurements

To assess the reliability of measurement of fetal cardiac ventricular volume, stroke volume, and ejection fraction with four-dimensional ultrasound using spatiotemporal image correlation (STIC). Volume datasets were collected from two sources: 24 from fetuses over a range of gestational ages and 12 from a miniature balloon model. Datasets were analyzed by three observers, repeatedly in 12 fetal datasets and all balloon datasets. Volume calculations were obtained by manually tracing multiple parallel slices (three-dimensional (3D) slice method). Measurement error was assessed by calculating standard errors of measurement (SEM) and coefficients of variation (CV). Reliability was assessed by calculating interobserver and intraobserver intraclass correlation coefficients (ICC). Measurement errors of balloon volumes were small and reliability was good (SEM <or= 0.07 mL, ICC 0.98-1.00). Fetal ventricle volume measurement error ranged from 0.09 to 0.20 mL and CV from 14.6 to 28.3%. Ventricular volume reliabilities for intra- and interobserver comparisons were greater than or equal to 0.94 and 0.75, respectively. Fetal stroke volume measurement error (SEM 0.17 mL), CV (21.9%) and reliability were measured (intraobserver ICC: left ventricle stroke volume (LVSV), 0.93 vs. right ventricle stroke volume (RVSV), 0.88; interobserver ICC: LVSV, 0.75 vs. RVSV, 0.86). The measurement error decreased with increasing operator experience. The reliability of ejection fraction calculations was poor (ICC < 0.7) for intra- and interobserver comparisons. Volume measurements obtained with STIC and 3D slice methods using a balloon model were reliable. In the fetus, measurement errors decreased with increasing operator experience, and reliability was better for stroke volume than for ejection fraction.

Role of Sonographic Automatic Volume Calculation in Measuring Fetal Cardiac Ventricular Volumes Using 4-Dimensional Sonography

The purpose of this study was to compare the agreement and reliability of virtual organ computer-aided analysis (VOCAL) and sonographic automatic volume calculation (sonoAVC) for measurements of ventricular volume from fetal heart data sets acquired by 4-dimensional sonography with spatiotemporal image correlation (STIC). We studied 45 volumes from fetuses with normal (n = 30) and abnormal (n = 15) hearts. Spatiotemporal image correlation data sets were frozen in end systole and end diastole, and ventricular volumes were measured with VOCAL and sonoAVC. The stroke volume was calculated from these measurements. Reliability and agreement of the two techniques were evaluated with intraclass correlation coefficients (ICCs), and proportionate Bland-Altman plots were constructed. The time necessary to complete the measurements with either technique was compared. Intraobserver and interobserver agreement of measurements was calculated. All data sets could be measured with both techniques. A high degree of reliability was observed between VOCAL and sonoAVC (left ventricular stroke volume ICC, 0.978; 95% confidence interval [CI], 0.957-0.989; right ventricular stroke volume ICC, 0.985; 95% CI, 0.972-0.992). The time necessary to measure the stroke volume was significantly shorter with sonoAVC (2.8 versus 11.7 minutes; P < .0001) than with VOCAL. Bland-Altman tests showed no clinically significant mean percent differences between stroke volume measurements obtained from each ventricle by the same observer or by 2 independent observers using either VOCAL or sonoAVC. There was good agreement between cardiac volumes measured with VOCAL and sonoAVC. Sonographic automatic volume calculation represents a rapid technique for estimating fetal stroke volume and promises to become the method of choice.

Repeatability and Reproducibility of Fetal Cardiac Ventricular Volume Calculations Using Spatiotemporal Image Correlation and Virtual Organ Computer-Aided Analysis

The objective of this study was to quantify the repeatability and reproducibility of fetal cardiac ventricular volumes obtained using spatiotemporal image correlation (STIC) and Virtual Organ Computer-Aided Analysis (VOCAL; GE Healthcare, Kretztechnik, Zipf, Austria). A technique was developed to compute ventricular volumes using the subfeature Contour Finder: Trace. Twenty-five normal pregnancies were evaluated for the following: (1) to compare the coefficient of variation (CV) of ventricular volumes obtained using 15 degrees and 30 degrees rotation; (2) to compare the CV between 3 methods of quantifying ventricular volumes: (a) Manual Trace, (b) Inversion Mode, and (c) Contour Finder: Trace; and (3) to determine repeatability by calculating agreement and reliability of ventricular volumes when each STIC was measured twice by 3 observers. Reproducibility was assessed by obtaining 2 STICs from each of 44 normal pregnancies. For each STIC, 2 ventricular volume calculations were performed, and agreement and reliability were evaluated. Additionally, measurement error was examined. (1) Agreement was better with 15 degrees rotation than 30 degrees (15 degrees: 3.6%; 95% confidence interval [CI], 3.0%-4.2%; versus 30 degrees: 7.1%; 95% CI, 5.8%-8.6%; P < .001); (2) ventricular volumes obtained with Contour Finder: Trace had better agreement than those obtained using either Inversion Mode (Contour Finder: Trace: 3.6%; 95% CI, 3.0%-4.2%; versus Inversion Mode: 6.0%; 95% CI, 4.9%-7.2%; P < .001) or Manual Trace (10.5%; 95% CI, 8.7%-12.5%; P < .001); (3) ventricular volumes were repeatable with good agreement and excellent reliability for both intraobserver and interobserver measurements; and (4) ventricular volumes were reproducible with negligible differences in agreement and good reliability. In addition, bias between STIC acquisitions was minimal (<1%; mean percent difference, -0.4%; 95% limits of agreement, -5.4%-5.9%). Fetal echocardiography using STIC and VOCAL allows repeatable and reproducible calculation of ventricular volumes with the subfeature Contour Finder: Trace.

Fetal cardiac ventricular volumes derived from real-time 3D ultrasound using a 2D matrix array transducer

Fetal cardiac ventricular volumes derived from real-time 3D ultrasound using a 2D matrix array transducer

Measurement of cardiac ventricular volumes using multidetector row computed tomography: comparison of two- and three-dimensional methods

This study compared a three-dimensional volumetric threshold-based method to a two-dimensional Simpson's rule based short-axis multiplanar method for measuring right (RV) and left ventricular (LV) volumes, stroke volumes, and ejection fraction using electrocardiography-gated multidetector computed tomography (MDCT) data sets. End-diastolic volume (EDV) and end-systolic volume (ESV) of RV and LV were measured independently and blindly by two observers from contrast-enhanced MDCT images using commercial software in 18 patients. For RV and LV the three-dimensionally calculated EDV and ESV values were smaller than those provided by two-dimensional short axis (10%, 5%, 15% and 26% differences respectively). Agreement between the two methods was found for LV (EDV/ESV: r=0.974/0.910, ICC=0.905/0.890) but not for RV (r=0.882/0.930, ICC=0.663/0.544). Measurement errors were significant only for EDV of LV using the two-dimensional method. Similar reproducibility was found for LV measurements, but the three-dimensional method provided greater reproducibility for RV measurements than the two-dimensional. The threshold value supported three-dimensional method provides reproducible cardiac ventricular volume measurements, comparable to those obtained using the short-axis Simpson based method.

The natriuretic peptides and their role in disorders of right heart dysfunction and pulmonary hypertension

Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are increased in conditions with cardiac ventricular volume and pressure overload. The general physiological and potential therapeutic roles of natriuretic peptides in respiratory disease, right ventricular (RV) dysfunction, and pulmonary arterial hypertension (PAH) are reviewed. BNP levels can be used to differentiate between dyspneic patients with a pure respiratory defect and those with RV dysfunction. BNP levels also correlate with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) in patients with PAH (atrial septal defect, chronic thromboembolic disease, and scleroderma). BNP is a predictor of mortality in patients with primary pulmonary hypertension (PPH). These are important clinical implications in that a noninvasive blood test may be used to identify high-risk patients for more invasive procedures such as cardiac catheterization. BNP or NT-proBNP measurements may also be used to guide therapy (e.g., pulmonary vasorelaxants) in PAH since upregulation of the natriuretic peptide pathway has been shown to reduce cardiac hypertrophy and PAH. Additionally, there may be therapeutic potential via recombinant BNP or neutral endopeptidase inhibitors in RV dysfunction and PAH.

Validation of right ventricular volume measurements by magnetic resonance imaging in small hearts using a fetal lamb model.

Cine-magnetic resonance (MR) imaging is established as an accurate method of determining cardiac ventricular volumes in adults but has not been validated for the smaller ventricular volumes found in infants. The purpose of the authors study was to evaluate the accuracy and reproducibility of MR imaging to measure small ventricle volumes. The volume of silicone-rubber casts of the right ventricle of 11 fetal lamb hearts was measured by MR imaging using different imaging planes and slice section thicknesses and by water displacement. The ventricle volumes of the 11 hearts ranged from 0.45 to 3.00 mL. Accurate and reproducible values for the right ventricle volumes were obtained by MR imaging. Thin sections (3 mm) in the axial plane produced the best results. Based on studies in the nonmoving heart, MR imaging can accurately measure the small ventricular volumes expected in infants.

Magnetic Resonance Measurement of Volumes Using a Phantom

Cine magnetic resonance (MR) is an established method for determining cardiac ventricular volumes in adults. The reported section slice thickness may be too thick for accurate measurement of ventricular volumes in infants and young children. In this article, acceptable slice thickness is established for cine MR in children. Balloons filled with a dilute gadolinium solution were immersed in a water bath. The balloons were scanned using a fast scan technique to simulate cine MR. Scanning was performed using different slice thicknesses. Volumes were calculated using previously reported techniques. These calculated volumes were compared to direct measurement of the balloon volumes using graduated syringes. The balloons varied in volume from 0.9 mL to 27.3 mL. Measurements using 3- and 5-mm slice thickness sections were found to be significantly more accurate than 10-mm slice thickness sections. Section thickness should be less than 1-cm when performing cine MR in infants and small children for measurement of ventricular volumes.

Calculation of right and left cardiac ventricular volumes. Method using standard computer equipment and biplane angiocardiograms.

A method has been described for the digital computer calculation of intracardiac ventricular volumes from orthogonal biplane x-ray images. It is directly applicable to both left and right ventricles and uses equipment commonly found in medium size computer centers. Validation of the method is presented using data from geometrical shapes and casts of human ventricular cavities.