Dynamic assessment of right ventricular volumes and function by real-time three-dimensional echocardiography: a comparison study with magnetic resonance imaging in 100 adult patients

Imaging in pulmonary hypertension: Focus on the role of echocardiography

Patients with pulmonary hypertension must be evaluated using a multimodality approach to ensure a correct diagnosis and basal evaluation as well as a prognostic assessment. Beyond the assessment of pulmonary pressures, the echocardiographical examination allows the evaluation of right ventricular adaptation to elevated afterload. Numbers of variables are commonly used in the assessment of the pulmonary hypertension patient in order to detect changes in right heart geometry, right-to-left interaction and right ventricular dysfunction. Whereas an isolated change in one echocardiographical variable is not meaningful, multiple echocardiographical variable modifications together provide accurate information. In this review, we will link pulmonary hypertension pathophysiological changes with echocardiographical indices and describe the clinical implications of echocardiographical findings.

Update on Perioperative Right Heart Assessment Using Transesophageal Echocardiography

Purpose of the review. This review aims to summarize recent findings relevant for perioperative 2- and 3-dimensional imaging of the right heart with transesophageal echocardiography. Special attention is given to developments that are likely to affect future approaches for prevention and therapy of perioperative right heart failure. Recent findings. Three-dimensional transesophageal echocardiography techniques are becoming more common for the evaluation of anatomy, volumes, and functional indices. Summary. Right heart failure continues to contribute to morbidity and mortality in the context of cardiothoracic surgery. The advent and widespread clinical use of innovative tools permitting more accurate echocardiographic assessment of the right heart will open the door to renewed interest in novel therapeutic strategies.

Reproducibility and correlations of right ventricular end-diastolic volume index measured by real-time three-dimensional echocardiography

BACKGROUND

To correlate right ventricular volumes measured by real-time three-dimensional echocardiography (RT3DE) with left ventricular volume indices in patients with or without left-sided heart diseases.

METHODS

For this retrospective, we reviewed 806 consecutive RT3DE examinations with quantitative evaluation of both the left and the right (RV) ventricle. We excluded cases of disease or surgery that would directly affect the size of the RV (eg, intracardiac shunt, significant tricuspid, or pulmonic regurgitation) as well as poor sonographic image quality, leaving a total of 701 studies for analysis. RV volumetric quantification was performed using dedicated software.

RESULTS

Linear regression analysis showed that left ventricular stroke volume index significantly correlated with RV end-diastolic volume index (RVEDVI) (r = 0.78, p < 0.0001). Overall, 4% (28 of 701) of the patients had RVEDVI lower than 50 ml/m(2) , and 12% (84 of 701) had RVEDVI greater than 100 ml/m(2) . Intraclass correlation coefficient ranged from 0.91 to 0.99 for intraobserver and 0.85 to 0.98 for interobserver reproducibility.

CONCLUSIONS

RT3DE was feasible and reproducible for quantifying RV volume. In patients without known primary RV pathology, RV volume strongly correlated with left ventricular stroke volume.

Echocardiography in pediatric pulmonary hypertension

Pulmonary hypertension (PH) can be a rapidly progressive and fatal disease. Although right heart catheterization remains the gold standard in evaluation of PH, echocardiography remains an important tool in screening, diagnosing, evaluating, and following these patients. In this article, we will review the important echocardiographic parameters of the right heart in evaluating its anatomy, hemodynamic assessment, systolic, and diastolic function in children with PH.

Clinical research priorities in adult congenital heart disease

BACKGROUND

Adult congenital heart disease (ACHD) clinicians are hampered by the paucity of data to inform clinical decision-making. The objective of this study was to identify priorities for clinical research in ACHD.

METHODS

A list of 45 research questions was developed by the Alliance for Adult Research in Congenital Cardiology (AARCC), compiled into a survey, and administered to ACHD providers. Patient input was sought via the Adult Congenital Heart Association at community meetings and online forums. The 25 top questions were sent to ACHD providers worldwide via an online survey. Each question was ranked based on perceived priority and weighted based on time spent in ACHD care. The top 10 topics identified are presented and discussed.

RESULTS

The final online survey yielded 139 responses. Top priority questions related to tetralogy of Fallot (timing of pulmonary valve replacement and criteria for primary prevention ICDs), patients with systemic right ventricles (determining the optimal echocardiographic techniques for measuring right ventricular function, and indications for tricuspid valve replacement and primary prevention ICDs), and single ventricle/Fontan patients (role of pulmonary vasodilators, optimal anticoagulation, medical therapy for preservation of ventricular function, treatment for protein losing enteropathy). In addition, establishing criteria to refer ACHD patients for cardiac transplantation was deemed a priority.

CONCLUSIONS

The ACHD field is in need of prospective research to address fundamental clinical questions. It is hoped that this methodical consultation process will inform researchers and funding organizations about clinical research topics deemed to be of high priority.

Validity of the surface electrocardiogram criteria for right ventricular hypertrophy: the MESA-RV Study (Multi-Ethnic Study of Atherosclerosis-Right Ventricle)

OBJECTIVES

The study aimed to assess the diagnostic properties of electrocardiographic (ECG) criteria for right ventricular hypertrophy (RVH) measured by cardiac magnetic resonance imaging (cMRI) in adults without clinical cardiovascular disease.

BACKGROUND

Current ECG criteria for RVH were based on cadaveric dissection in small studies.

METHODS

MESA (Multi-Ethnic Study of Atherosclerosis) performed cMRIs with complete right ventricle (RV) interpretation on 4,062 participants without clinical cardiovascular disease. Endocardial margins of the RV were manually contoured on diastolic and systolic images. The ECG screening criteria for RVH from the 2009 American Heart Association Recommendations for Standardization and Interpretation of the ECG were examined in participants with and without left ventricular (LV) hypertrophy or reduced ejection fraction. RVH was defined using sex-specific normative equations based on age, height, and weight.

RESULTS

The study sample with normal LV morphology and function (n = 3,719) was age 61.3 ± 10.0 years, 53.5% female, 39.6% Caucasian, 25.5% African American, 21.9% Hispanic, and 13.0% Asian. The mean body mass index was 27.9 ± 5.0 kg/m(2). A total of 6% had RVH, which was generally mild. Traditional ECG criteria were specific (many >95%) but had low sensitivity for RVH by cMRI. The positive predictive values were not sufficiently high as to be clinically useful (maximum 12%). The results did not differ based on age, sex, race, or smoking status, or with the inclusion of participants with abnormal LV mass or function. Classification and regression tree analysis revealed that no combination of ECG variables was better than the criteria used singly.

CONCLUSIONS

The recommended ECG screening criteria for RVH are not sufficiently sensitive or specific for screening for mild RVH in adults without clinical cardiovascular disease.

Assessment of right ventricular volumes in hypoplastic left heart syndrome by real-time three-dimensional echocardiography: comparison with cardiac magnetic resonance imaging

BACKGROUND

Accurate assessment of right ventricular (RV) volumes and function is important in patients with hypoplastic left heart syndrome (HLHS). We prospectively sought to determine the reproducibility of three-dimensional (3D) echocardiography and its agreement with cardiac magnetic resonance imaging (CMR) in HLHS.

METHODS AND RESULTS

Twenty-eight patients underwent CMR followed immediately by transthoracic 3D echocardiography under general anaesthesia. Semi-automated border detection software was used to determine echocardiographic RV volumes. Inter- and intra-observer variability, correlation and levels of agreement between techniques were determined. The median age was 0.37 years (0.18-9.28 years) and weight 6.24 kg (3.42-32.50 kg). Intra- and inter-observer variability was excellent for both techniques. Median (range) measurements for 3D echocardiography and CMR were; end-diastolic volume (EDV) 23.6 mL (6.5-63.2) and 30.6 mL (11.8-87.9), end-systolic volume (ESV) 12.6 mL (3.7-37.0) and 14.9 mL (5.8-33.9), stroke volume (SV) 11.2 mL (2.8-33.0) and 17.1 mL (6.0-54.1), ejection fraction (EF) 48.2% (31.2-64.9), and 56.5% (42.7-72.2). Correlation coefficients were r = 0.85, 0.84, 0.83, and 0.74, respectively (P < 0.01 for all). Volumetric data were expressed as a percentage of the echocardiographic volume to CMR volume. When compared with CMR, 3D echocardiography underestimated EDV, ESV and SV by 26.7% (SD ± 20.2), 10.6% (±28.1), and 37.5% (±20.1), respectively. The difference in volume appeared largest at low ventricular volumes. EF was 8.3% (±7.3) lower by 3D echocardiography compared with CMR.

CONCLUSION

Both 3D echocardiography and CMR volumes appear highly reproducible. Measurements obtained by 3D echocardiography are significantly lower than those obtained by CMR, with wide limits of agreement such that these two methods cannot be used interchangeably.

Three-dimensional modeling of the right ventricle from two-dimensional transthoracic echocardiographic images: utility of knowledge-based reconstruction in pulmonary arterial hypertension

BACKGROUND

Right ventricular (RV) volume and functional assessments are essential in the management of pulmonary arterial hypertension but are often difficult to perform. Three-dimensional (3D) echocardiography is limited by acoustic dropout of the RV free wall in dilated ventricles. The aim of this study was to test the hypothesis that knowledge-based reconstruction, a novel method for 3D modeling of RV endocardium from two-dimensional echocardiographic images, could provide accurate measurements of RV volumes and systolic function.

METHODS

Twenty-seven patients with pulmonary arterial hypertension were prospectively recruited for same-day echocardiography and cardiovascular magnetic resonance (CMR), which was used as a reference standard. Two-dimensional transthoracic echocardiographic images were acquired with 3D spatial localization equipment to allow 3D reconstruction. Image analysis was performed with dedicated software to obtain end-diastolic volume (EDV) and end-systolic volume (ESV) and RV ejection fraction (EF). The method of disks was used to determine RV volumes on CMR.

RESULTS

Echocardiographic RV volumes correlated well with CMR (EDV, R = 0.87; ESV, R = 0.88; EF, R = 0.75). For interobserver analyses, coefficients of variability were 7.8 ± 7.0% for EDV, 10.2 ± 8.0% for ESV, and 15.4 ± 13.8% for EF. For intraobserver analyses, coefficients of variability were 7.1 ± 5.1% for EDV, 8.3 ± 7.0% for ESV, and 10.9 ± 9.2% for EF. On Bland-Altman analyses, volumes obtained on transthoracic echocardiography (TTE) were slightly larger than those obtained by CMR (ΔEDVTTE-CMR, 5.8 ± 33.7 mL; ΔESVTTE-CMR, 3.5 ± 27.8 mL), whereas EFs tended to be slightly higher by CMR (ΔEFCMR-TTE, 0.5 ± 6.5%).

CONCLUSIONS

Knowledge-based reconstruction provides accurate and reproducible measurements of RV volumes in patients with pulmonary arterial hypertension. Larger studies are needed to confirm these results and to determine the practicality of this approach in daily practice and as an end point in clinical trials.

Evaluation of right ventricular volume and ejection fraction by gated (18)F-FDG PET in patients with pulmonary hypertension: comparison with cardiac MRI and CT

BACKGROUND

Right ventricular (RV) function is a powerful predictor of survival in patients with pulmonary hypertension (PH), but noninvasively assessing RV function remains a challenge. The aim of this study was to prospectively compare gated (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) myocardial imaging (gated PET), cardiac magnetic resonance (CMR), and cardiac computed tomography (CCT) for the assessment of RV volume and ejection fraction in patients with PH.

METHODS

Twenty-three consecutive patients aged more than 16 years diagnosed with PH were included. All patients underwent gated PET, CMR, and CCT within 7 days. Right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), and right ventricular ejection fraction (RVEF) were calculated by three imaging modalities. RV (18)F-FDG uptake was determined as RV-corrected standardized uptake value (SUV), and the ratio of RV to left ventricular (LV)-corrected SUV (Corrected SUV R/L).

RESULTS

Gated PET showed a moderate correlation (r = 0.680, P < .001) for RVEDV, good correlation for RVESV (r = 0.757, P < .001) and RVEF (r = 0.788, P < .001) with CMR, and good correlation for RVEDV (r = 0.767, P < .001), RVESV (r = 0.837, P < .001), and RVEF (r = 0.730, P < .001) with CCT. Bland-Altman analysis revealed systematic underestimation of RVEDV and RVESV and overestimation of RVEF with gated PET compared with CMR and CCT. The correlation between RVESV (r = 0.863, P < .001), RVESV (r = 0.903, P < .001), and RVEF (r = 0.853, P < .001) of CMR and those of CCT was excellent; Bland-Altman analysis showed only a slight systematic variation between CMR and CCT. There were statistically significant negative correlations between RV-corrected SUV and RVEF-CMR (r = -0.543, P < .01), Corrected SUV R/L and RVEF-CMR (r = -0.521, P < .05), RV-corrected SUV and RVEF-CCT (r = -0.429, P < .05), Corrected SUV R/L and RVEF-CCT (r = -0.580, P < .01), respectively.

CONCLUSION

Gated PET had moderate-to-high correlation with CMR and CCT in the assessments of RV volume and ejection fraction. It is an available method for simultaneous assessing of RV function and myocardial glucose metabolism in patients with PH.

Advantages of real time three-dimensional echocardiography in the assessment of right ventricular volumes and function in patients with pulmonary hypertension compared with conventional two-dimensional echocardiography

BACKGROUND

In recent years, right ventricular (RV) function has acquired greater relevance as a clinical and prognostic marker in many physiopathological conditions. The study aims to point out the value of real time three-dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI) in the evaluation of patients affected by pulmonary hypertension (PH), compared with conventional two-dimensional (2D) echocardiography.

METHODS

We enrolled 44 subjects affected by PH who underwent 2D and Doppler echocardiography, RT 3D Echocardiography and TDI evaluation of the RV, and a healthy control group. PH itself can induce severe functional and structural abnormalities of the RV, such as RV hypertrophy, RV dilation, and RV systolic and diastolic dysfunction.

RESULTS

In this study, RV FAC, and TAPSE showed marked alterations in patients with PH compared to the control group (C): (RVFAC: [PH] 0.29 ± 0.07 vs. [C] 0.49 ± 0.05%, P < 0.0001; TAPSE: [PH] 15.3 ± 3.2 vs. [C] 21.1 ± 2.6 mm, P > 0.0001). The 3D RV end-diastolic volume was significantly higher in PH than in C (PH) (138.7 ± 25.3 vs. [C] 82.8 ± 12.5 mL, P < 0.0001] as well as 3D RV end-systolic volume (PH) (97.6 ± 21.5 vs. [C] 39.3 ± 9.5 mL, P < 0.0001). The 3D RV ejection fraction (EF) was significantly lower in the pulmonary hypertension group than in healthy subjects (31.8 ± 6.8 vs. [C] 52.5 ± 4.7%, P < 0.0001).

CONCLUSIONS

In patients with PH, evaluation of the RV diastolic and systolic volume and EF by RT3DE has shown a higher discriminating power in comparison, respectively, with 2DRV diastolic area and the relative fractional area changes.

Right ventricular systolic function in organic mitral regurgitation: impact of biventricular impairment

BACKGROUND

To assess the prevalence, determinants, and prognosis value of right ventricular (RV) ejection fraction (EF) impairment in organic mitral regurgitation.

METHODS AND RESULTS

Two hundred eight patients (62±12 years, 138 males) with chronic organic mitral regurgitation referred to surgery underwent an echocardiography and biventricular radionuclide angiography with regional function assessment. Mean RV EF was 40.4±10.2%, ranging from 10% to 65%. RV EF was severely impaired (≤35%) in 63 patients (30%), and biventricular impairment (left ventricular EF<60% and RV EF≤35%) was found in 34 patients (16%). Pathophysiologic correlates of RV EF were left ventricular septal function (β=0.42, P<0.0001), left ventricular end-diastolic diameter index (β=-0.22, P=0.002), and pulmonary artery systolic pressure (β=-0.14, P=0.047). Mitral effective regurgitant orifice size (n=84) influenced RV EF (β=-0.28, P=0.012). In 68 patients examined after surgery, RV EF increased strongly (27.5±4.3-37.9±7.3, P<0.0001) in patients with depressed RV EF, whereas it did not change in others (P=0.91). RV EF ≤35% impaired 10-year cardiovascular survival (71.6±8.4% versus 89.8±3.7%, P=0.037). Biventricular impairment dramatically reduced 10-year cardiovascular survival (51.9±15.3% versus 90.3±3.2%, P<0.0001; hazard ratio, 5.2; P<0.0001) even after adjustment for known predictors (hazard ratio, 4.6; P=0.004). Biventricular impairment reduced also 10-year overall survival (34.8±13.0% versus 72.6±4.5%, P=0.003; hazard ratio, 2.5; P=0.005) even after adjustment for known predictors (P=0.048).

CONCLUSIONS

In patients with organic mitral regurgitation referred to surgery, RV function impairment is frequent (30%) and depends weakly on pulmonary artery systolic pressure but mainly on left ventricular remodeling and septal function. RV function is a predictor of postoperative cardiovascular survival, whereas biventricular impairment is a powerful predictor of both cardiovascular and overall survival.

Quantifying pulmonary regurgitation and right ventricular function in surgically repaired tetralogy of Fallot: a comparative analysis of echocardiography and magnetic resonance imaging

BACKGROUND

Patients with repaired tetralogy of Fallot are monitored for pulmonary regurgitation (PR) and right ventricular (RV) function. We sought to compare measures of PR and RV function on echocardiogram to those on cardiac magnetic resonance (CMR) and to develop a new tool for assessing PR by echocardiogram.

METHODS AND RESULTS

Patients with repaired tetralogy of Fallot (n=143; 12.5±3.2 years) had an echocardiogram and CMR within 3 months of each other. On echocardiogram, RV function was assessed by (1) Doppler tissue imaging of the RV free wall and (2) myocardial performance index. The ratio of diastolic and systolic time-velocity integrals measured by Doppler of the main pulmonary artery was calculated. CMR variables included RV ejection fraction, RV volumes, and pulmonary regurgitant fraction (RF). Pulmonary regurgitation was graded as mild (RF<20%), moderate (RF=20-40%), and severe (RF>40%). On CMR, RF was 34+17% and RV ejection fraction was 61+8%. Echocardiography had good sensitivity identifying cases with RF>20% (sensitivity 97%; 95% CI: 92-99%) but overestimated the amount of PR when RF<20% (false-positive rate 36%; 95% CI: 18-57%). The diastolic and systolic time-velocity integrals on echocardiogram showed moderate correlation with RF on CMR (R=0.60; P<0.0001). On CMR, RF of 20% and 40% corresponded with a diastolic and systolic time-velocity integral of 0.49 (95% CI: 0.44-0.56) and 0.72 (95% CI: 0.68-0.76), respectively. RV myocardial performance index correlated modestly with RV ejection fraction (r=-0.33; P<0.001).

CONCLUSIONS

This study suggests that the diastolic and systolic time-velocity integrals ratio may make a modest contribution to the overall assessment of PR in patients with repaired tetralogy of Fallot and warrants further investigation. However, echocardiography continues to have a limited ability to quantify PR and RV function as compared with CMR.

Transthoracic echocardiography in children and young adults with congenital heart disease

Transthoracic echocardiography (TTE) is the first-line tool for diagnosis and followup of pediatric and young adult patients with congenital heart disease (CHD). Appropriate use of TTE can reduce the need for more invasive modalities, such as cardiac catheterization and cardiac magnetic resonance imaging. New echocardiographic techniques have emerged more recently: tissue Doppler imaging, tissue tracking (strain and strain rate), vector velocity imaging (VVI), myocardial performance index, myocardial acceleration during isovolumic acceleration (IVA), the ratio of systolic to diastolic duration (S/D ratio), and two dimensional measurements of systolic right ventricular (RV) function (e.g., tricuspid annular plane systolic excursion, TAPSE). These may become valuable indicators of ventricular performance, compliance, and disease progression. In addition, three-dimensional (3D) echocardiography when performed for the assessment of valvular function, device position, and ventricular volumes is being integrated into routine clinical care. In this paper, the potential use and limitations of these new echocardiographic techniques in patients with CHD are discussed. A particular focus is on the echocardiographic assessment of right ventricular (RV) function in conditions associated with increased right ventricular volume (e.g., pulmonary regurgitation after tetralogy of Fallot repair) or pressure (e.g., pulmonary hypertension) in children and young adults.

Current clinical applications of transthoracic three-dimensional echocardiography

The advent of three-dimensional echocardiography (3DE) has significantly improved the impact of non-invasive imaging on our understanding and management of cardiac diseases in clinical practice. Transthoracic 3DE enables an easier, more accurate and reproducible interpretation of the complex cardiac anatomy, overcoming the intrinsic limitations of conventional echocardiography. The availability of unprecedented views of cardiac structures from any perspective in the beating heart provides valuable clinical information and new levels of confidence in diagnosing heart disease. One major advantage of the third dimension is the improvement in the accuracy and reproducibility of chamber volume measurement by eliminating geometric assumptions and errors caused by foreshortened views. Another benefit of 3DE is the realistic en face views of heart valves, enabling a better appreciation of the severity and mechanisms of valve diseases in a unique, noninvasive manner. The purpose of this review is to provide readers with an update on the current clinical applications of transthoracic 3DE, emphasizing the incremental benefits of 3DE over conventional two-dimensional echocardiography.

Review of novel clinical applications of advanced, real-time, 3-dimensional echocardiography

Advances in computer processing speed and memory along with the advent of the microbeam former that can sample an entire crystal of the ultrasound transducer made possible the performance of 3-dimensional echocardiography in real time (RT3DE). The miniaturization of a 3-dimensional transducer permitting its extension to transesophageal mode rapidly expanded its use in a variety of conditions. Recent development of user-friendly automated/semiautomated cropping and display software may make it rather simple, even for the novice to gather useful information from RT3DE. We discuss the background, technique, and cutting-edge research and novel clinical applications of advanced RT3DE, including left ventricular dyssynchrony assessment, 3-D speckle tracking, myocardial contrast echocardiography, complete 4-dimensional (4-D) shape and motion analysis of the left ventricle, 4-D volumetric analysis of the right ventricle, 3-D volume rendering of the mitral valve, and other percutaneous and surgical procedural applications.

Single beat 3D echocardiography for the assessment of right ventricular dimension and function after endurance exercise: Intraindividual comparison with magnetic resonance imaging

Background

Our study compares new single beat 3D echocardiography (sb3DE) to cardiovascular magnetic resonance imaging (CMR) for the measurement of right ventricular (RV) dimension and function immediately after a 30 km run. This is to validate sb3DE against the "gold standard" CMR and to bring new insights into acute changes of RV dimension and function after endurance exercise.

Methods

21 non-elite male marathon runners were examined by sb3DE (Siemens ACUSON SC2000, matrix transducer 4Z1c, volume rates 10-29/s), CMR (Siemens Magnetom Avanto, 1,5 Tesla) and blood tests before and immediately after each athlete ran 30 km. The runners were not allowed to rehydrate after the race. The order of sb3DE and CMR examination was randomized.

Results

Sb3DE for the acquisition of RV dimension and function was feasible in all subjects. The decrease in mean body weight and the significant increase in hematocrit indicated dehydration. RV dimensions measured by CMR were consistently larger than measured by sb3DE.

Neither sb3DE nor CMR showed a significant difference in the RV ejection fraction before and after exercise. CMR demonstrated a significant decrease in RV dimensions. Measured by sb3DE, this decrease of RV volumes was not significant.

Conclusion

First, both methods agree well in the acquisition of systolic RV function. The dimensions of the RV measured by CMR are larger than measured by sb3DE. After exercise, the RV volumes decrease significantly when measured by CMR compared to baseline.

Second, endurance exercise seems not to induce acute RV dysfunction in athletes without rehydration.

Manual correction of semi-automatic three-dimensional echocardiography is needed for right ventricular assessment in adults; validation with cardiac magnetic resonance

BACKGROUND

Three-dimensional echocardiography (3DE) and semi-automatic right ventricular delineation has been proposed as an appropriate method for right ventricle (RV) evaluation. We aimed to examine how manual correction of semi-automatic delineation influences the accuracy of 3DE for RV volumes and function in a clinical adult setting using cardiac magnetic resonance (CMR) as the reference method. We also examined the feasibility of RV visualization with 3DE.

METHODS

62 non-selected patients were examined with 3DE (Sonos 7500 and iE33) and with CMR (1.5T). Endocardial RV contours of 3DE-images were semi-automatically assessed and manually corrected in all patients. End-diastolic (EDV), end-systolic (ESV) volumes, stroke volume (SV) and ejection fraction (EF) were computed.

RESULTS

53 patients (85%) had 3DE-images feasible for examination. Correlation coefficients and Bland Altman biases between 3DE with manual correction and CMR were r = 0.78, -22 ± 27 mL for EDV, r = 0.83, -7 ± 16 mL for ESV, r = 0.60, -12 ± 18 mL for SV and r = 0.60, -2 ± 8% for EF (p < 0.001 for all r-values). Without manual correction r-values were 0.77, 0.77, 0.70 and 0.49 for EDV, ESV, SV and EF, respectively (p < 0.001 for all r-values) and biases were larger for EDV, SV and EF (-32 ± 26 mL, -21 ± 15 mL and - 6 ± 9%, p ≤ 0.01 for all) compared to manual correction.

CONCLUSION

Manual correction of the 3DE semi-automatic RV delineation decreases the bias and is needed for acceptable clinical accuracy. 3DE is highly feasible for visualizing the RV in an adult clinical setting.

Non-Invasive Imaging for Congenital Heart Disease: Recent Innovations in Transthoracic Echocardiography

Transthoracic echocardiography (TTE) is an important tool for diagnosis and follow-up of patients with congenital heart disease (CHD). Appropriate use of TTE can reduce the need for more invasive and complex modalities, such as cardiac catheterization and cardiac magnetic resonance imaging. New echocardiographic techniques have emerged for the assessment of ventricular systolic and diastolic function: Tissue Doppler imaging, tissue tracking, strain and strain rate imaging, vector velocity imaging (VVI), myocardial performance index, myocardial acceleration during isovolumic contraction (IVA), the ratio of systolic to diastolic duration (S/D ratio), and other measurements of systolic right ventricular (RV) function like tricuspid annular plane systolic excursion (TAPSE). These modalities may become valuable indicators of ventricular performance, compliance and disease progression, with the caveat of preload-dependency of the variables measured. In addition, three-dimensional (3D) echocardiography for the assessment of cardiac anatomy, valvular function, device position, ventricular volumes and ejection fraction is integrated into routine clinical care. In this review, we discuss the potential use and limitations of these new echocardiographic techniques in patients with CHD. A particular focus is on the echocardiographic assessment of right ventricular (RV) function by means of tissue Doppler imaging, tissue tracking, and three-dimensional imaging, in conditions associated with increased right ventricular volume or pressure load.

Echocardiographic evaluation of the single right ventricle in congenital heart disease: results of new techniques

Right ventricular (RV) function is increasingly recognized as having prognostic significance in various disease processes. The current gold standard for noninvasive measurement of RV function is cardiac magnetic resonance imaging; however, because of practical considerations, echocardiography remains the most often used modality for evaluating the RV. In the past, because of its complex morphology, echocardiographic assessment of the RV was usually qualitative in nature. Current advances in echocardiographic techniques have been able to overcome some of the previous limitations and thus quantification of RV function is increasingly being performed. In addition, recent echocardiographic guidelines for evaluating the RV have been published to aid in standardizing practice. The evaluation of RV function almost certainly has no greater importance than in the congenital heart population, especially in those patients that have a single RV acting as the systemic ventricle. As this complex population continues to increase in number, accurate and precise evaluation of RV function will be a major issue in determining clinical care.

Functional assessment of the left atrium by real-time three-dimensional echocardiography using a novel dedicated analysis tool: initial validation studies in comparison with computed tomography

AIMS

A novel real-time three-dimensional echocardiography (RT3DE) analysis tool specifically designed for evaluation of the left atrium enables comprehensive evaluation of left atrial (LA) size, global, and regional function using a dynamic 16-segment model. The aim of this study was the initial validation of this method using computed tomography (CT) as the method of reference.

METHODS AND RESULTS

The study population consisted of 34 prospectively enrolled patients with clinical indication for pulmonary vein isolation. A dynamic polyhedron model of the left atrium was generated using RT3DE. LA maximum and minimum volumes (LA(max)/LA(min)) and emptying fraction (LAEF) were determined and compared with the results obtained by CT. High correlations between RT3DE and CT were found for LA(max) (r = 0.92, P < 0.001), LA(min) (r = 0.95, P < 0.001), and LAEF (r = 0.82, P < 0.001). LA(max) and LA(min) were lower by RT3DE than by CT (95.0 ± 44.7 vs. 119.8 ± 50.5 mL, P < 0.001 and 58.1 ± 41.3 vs. 83.3 ± 52.6 mL, P < 0.001, respectively), whereas LAEF was measured higher by RT3DE (42.8 ± 15.2 vs. 34.2 ± 15.4%, P < 0.001, respectively). RT3DE measurements closely correlated in terms of intra-observer (intra-class correlation r = 0.99, r = 0.99, r = 0.96, respectively) and inter-observer variability (r = 0.97, r = 0.98, r = 0.88, respectively).

CONCLUSIONS

LA volumes and EF as assessed by RT3DE correlate highly with CT measurements, albeit there is some bias between the imaging modalities. Most importantly, RT3DE measurements using the novel dedicated LA analysis tool are robust in terms of observer variability and thus suitable for follow-up analyses.

Right ventricular ejection fraction <20% is an independent predictor of mortality but not of hospitalization in older systolic heart failure patients

BACKGROUND

Reduced right ventricular ejection fraction (RVEF) is associated with poor outcomes in patients with chronic systolic heart failure (HF). Although most HF patients are older adults, little is known about the relationship between low RVEF and outcomes in older adults with systolic HF.

METHODS

Of the 2008 Beta-Blocker Evaluation of Survival Trial (BEST) participants with systolic HF (left ventricular ejection fraction ≤ 35%) 822 were ≥ 65 years and had data on baseline RVEF estimated by gated-equilibrium radionuclide ventriculography. Using RVEF ≥ 40% (n = 308) as reference, we examined association of RVEF 30-39% (n = 214), 20-29% (n = 206) and <20% (n = 94) with outcomes using Cox regression models.

RESULTS

All-cause mortality occurred in 36%, 40%, 39% and 56% of patients with RVEF ≥ 40%, 30-39%, 20-29% and <20% respectively. Compared with RVEF ≥ 40%, unadjusted hazard ratios (HR) and 95% confidence intervals (CI) for all-cause mortality associated with RVEF 30-39%, 20-29% and <20% were 1.19 (0.90-1.57; P = 0.220), 1.13 (0.84-1.51; P = 0.423) and 1.97 (1.43-2.73; P<0.001) respectively. Respective multivariable-adjusted HR's (95% CI's) for all-cause mortality were 1.19 (0.88-1.60; P = 0.261), 1.00 (0.73-1.39; P = 0.982) and 1.70 (1.14-2.53; P = 0.009). Adjusted HR's (95% CI's) associated with RVEF <20% (versus ≥ 40%) for cardiovascular mortality and HF mortality were 1.79 (1.17-2.76; P = 0.008) and 1.97 (1.02-3.83; P = 0.045) respectively. RVEF had no independent association with sudden cardiac death, all-cause or HF hospitalization.

CONCLUSIONS

Abnormally low RVEF is a significant independent predictor of mortality, but not of HF hospitalization, in older adults with systolic HF.

Imaging the right ventricle--current state of the art

The right ventricle has long been the 'forgotten ventricle', as it is difficult to image owing to its complex morphology, its thin wall with coarse trabeculations, and its anterior position within the chest. Developments in cardiac magnetic resonance imaging (CMR) and echocardiography have provided new insights into right ventricular (RV) structure and function. RV performance seems to be an important determinant of clinical status and long-term outcome in patients with pulmonary hypertension, cardiomyopathies, and, especially, in patients with congenital heart disease. A variety of different parameters can be measured to assess RV function, but a lot of uncertainty remains on how to assess RV performance in daily clinical practice and which measurements to use in clinical decision-making. CMR is currently considered the reference technique for RV volumetry and calculation of ejection fraction. Various echocardiographic techniques can provide reliable information on RV dimensions and RV systolic and diastolic function that can be used in clinical follow-up. The introduction of newer echocardiographic techniques, such as three-dimensional echocardiography, tissue Doppler ultrasonography, and ultrasound strain imaging, challenge the leading role of CMR in RV functional assessment, but further validation and accumulation of data are required before these techniques can play a key part in clinical decision-making.