Non-invasive investigations of the right heart: how and why?

Evaluation of right ventricular performance in patients with postoperative congenital heart disease using Doppler tissue imaging and cardiopulmonary bypass indices: A prospective cohort study

Background and Aims

Postoperative cardiac outcomes after intracardiac repair (ICR) are determined by numerous factors whereas right ventricle (RV) dysfunction is considered essential for them, as only few studies attempted to evaluate it postsurgically. RV's function is supposed to be the strong prognostic factor for patients diagnosed with congenital heart defects; therefore, assessing it is the main objective of the study.

Methods

This is a prospective single-centered cohort study performed on 50 pediatric patients with congenital heart disease (CHD) who underwent ICR between January 2019 and January 2022. All patients underwent echocardiographic assessment of RV function via tricuspid annular plane systolic excursion (TAPSE) and fractional area change (FAC) at 1, 24, and 48 h. After surgery, where pre- and postoperative RV pressure, cardiopulmonary bypass (CPB), and aortic cross-clamp (ACC) time were assessed. Similarly ventilation intensive care unit (ICU) and hospital stay times and mediastinal drainage were also monitored.

Results

The mean ± standard deviation for pre- and postoperative RV pressure was 49.1 ± 16.12 and 42.7 ± 2.9 mmHg, respectively, whereas that for pre- and postoperative pulmonary artery pressure was 30.4 ± 2.6 and 24.2 ± 12.9 mmHg, with p value of <0.002 and <0.001, respectively. The mean ± standard deviation of CPB and ACC times was 120.92 ± 74.17 and 78.44 ± 50.5 min accordingly, while those for mean ± standard deviation of ventilation time, mediastinum chest drainage, ICU and hospital stays were 30.36 ± 54.04, 43.78 ± 46.7 min, 5.9 ± 4.01 h, were 30.36 ± 54.0, 43.78 ± 46.7 min, 5.9 ± 4.01 and 10.3 ± 4.83 h, respectively.

Conclusions

RV dysfunction plays the important role in longer recovery and intraoperative time, while its effect is mostly transient. The use of TAPSE and FAC methods is valuable in the evaluation of postoperative outcomes, and the former proved to be more effective.

Correlation Between 2D Strain and Classic Echocardiographic Indices in the Diagnosis of Right Ventricular Dysfunction in COPD

Purpose

This study aims to define which of the right ventricular myocardial deformation indices best correlates with the classic echocardiographic measurements and indices of right ventricular (RV) dysfunction in patients with stable chronic obstructive pulmonary disease (COPD).

Patients and Methods

Ninety-one patients with stable COPD underwent clinical evaluation, spirometry, a 6-minute walk test, and echocardiographic examination. Patients were divided into two groups: “with RV dysfunction” (≥1 classic parameter) and “without RV dysfunction”. We used speckle tracking to estimate myocardial deformation. For all analyses, results were considered significant if p < 0.05.

Results

The mean age across all participants was 65 ± 9 years, with 53% (48/91) being male. Patients in the group with RV dysfunction were able to walk shorter distances and had higher estimated right ventricular systolic pressure (RVSP) and mean pulmonary arterial pressure (mPAP). The RV free wall longitudinal strain (RVFWLS) was the only deformation indices that showed a significant correlation with all classic measurements and indices in the diagnosis of RV dysfunction (Wald test, 10.24; p < 0.01; odds ratio, 1.61). In the ROC curve analysis, the absolute value <20% was the lowest cut-off point of this index for detection of RV dysfunction (AUC = 0.93, S: 95.8%, and E: 88%).

Conclusion

In COPD patients, RVFWLS is the myocardial deformation index that best correlates with classic echocardiographic parameters for the diagnosis of RV dysfunction using <20% as a cut-off point.

Whole-Heart High-Resolution Late Gadolinium Enhancement: Techniques and Clinical Applications

In cardiovascular magnetic resonance, late gadolinium enhancement (LGE) has become the cornerstone of myocardial tissue characterization. It is widely used in clinical routine to diagnose and characterize the myocardial tissue in a wide range of ischemic and nonischemic cardiomyopathies. The recent growing interest in imaging left atrial fibrosis has led to the development of novel whole‐heart high‐resolution late gadolinium enhancement (HR‐LGE) techniques. Indeed, conventional LGE is acquired in multiple breath‐holds with limited spatial resolution: ~1.4–1.8 mm in plane and 6–8 mm slice thickness, according to the Society for Cardiovascular Magnetic Resonance standardized guidelines. Such large voxel size prevents its use in thin structures such as the atrial or right ventricular walls. Whole‐heart 3D HR‐LGE images are acquired in free breathing to increase the spatial resolution (up to 1.3 × 1.3 × 1.3 mm³) and offer a better detection and depiction of focal atrial fibrosis. The downside of this increased resolution is the extended scan time of around 10 min, which hampers the spread of HR‐LGE in clinical practice. Initially introduced for atrial fibrosis imaging, HR‐LGE interest has evolved to be a tool to detect small scars in the ventricles and guide ablation procedures. Indeed, the detection of scars, nonvisible with conventional LGE, can be crucial in the diagnosis of myocardial infarction with nonobstructed coronary arteries, in the detection of the arrhythmogenic substrate triggering ventricular arrhythmia, and improve the confidence of clinicians in the challenging diagnoses such as the arrhythmogenic right ventricular cardiomyopathy. HR‐LGE also offers a precise visualization of left ventricular scar morphology that is particularly useful in planning ablation procedures and guiding them through the fusion of HR‐LGE images with electroanatomical mapping systems. In this narrative review, we attempt to summarize the technical particularities of whole‐heart HR‐LGE acquisition and provide an overview of its clinical applications with a particular focus on the ventricles.

Cardiac Dysfunction in Severely Burned Patients: Current Understanding of Etiology, Pathophysiology, and Treatment

Patients who experience severe burn injuries face a massive inflammatory response resulting in hemodynamic and cardiovascular complications. Even after immediate and appropriate resuscitation, removal of burn eschar and covering of open areas, burn patients remain at high risk for serious morbidity and mortality. As a result of the massive fluid shifts following the initial injury, along with large volume fluid resuscitation, the cardiovascular system is critically affected. Further, increased inflammation, catecholamine surge, and hypermetabolic syndrome impact cardiac dysfunction, which worsens outcomes of burn patients. This review aimed to summarize the current knowledge about the effect of burns on the cardiovascular system.A comprehensive search of the PubMed and Embase databases and manual review of articles involving effects of burns on the cardiovascular system was conducted.Many burn units use multimodal monitors (e.g., transpulmonary thermodilution) to assess hemodynamics and optimize cardiovascular function. Echocardiography is often used for additional evaluations of hemodynamically unstable patients to assess systolic and diastolic function. Due to its noninvasive character, echocardiography can be repeated easily, which allows us to follow patients longitudinally.The use of anabolic and anticatabolic agents has been shown to be beneficial for short- and long-term outcomes of burn survivors. Administration of propranolol (non-selective β-receptor antagonist) or oxandrolone (synthetic testosterone) for up to 12 months post-burn counteracts hypermetabolism during hospital stay and improves cardiac function.A comprehensive understanding of how burns lead to cardiac dysfunction and new therapeutic options could contribute to better outcomes in this patient population.

Understanding and recognition of the right ventricular function and dysfunction via a numerical study

The role played by the right ventricular (RV) dysfunction has long been underestimated in clinical practice. Recent findings are progressively confirming that when the RV efficiency deteriorates both the right and the left circulation is (significantly) affected, but studies dedicated to a detailed description of RV hemodynamic role still lack. In response to such a gap in knowledge, this work proposes a numerical model that for the first time evaluates the effect of isolated RV dysfunction on the whole circulation. Lumped parameter modelling was applied to represent the physio-pathological hemodynamics. Different grades of impairment were simulated for three dysfunctions i.e., systolic, diastolic, and combined systolic and diastolic. Hemodynamic alterations (i.e., of blood pressure, flow, global hemodynamic parameters), arising from the dysfunctions, are calculated and analysed. Results well accord with clinical observations, showing that RV dysfunction significantly affects both the pulmonary and systemic hemodynamics. Successful verification against in vivo data proved the clinical potentiality of the model i.e., the capability of identifying the degree of RV impairment for given hemodynamic conditions. This study aims at contributing to the improvement of RV dysfunction recognition and treatment, and to the development of tools for the clinical management of pathologies involving the right heart.

Prevalence and Prognostic Significance of Right Ventricular Dysfunction in Patients With Hypertrophic Cardiomyopathy

Few data are available regarding the prevalence and clinical significance of right ventricular systolic dysfunction (RVSD) in hypertrophic cardiomyopathy (HC) patients. This study aimed to evaluate right ventricular (RV) systolic function by cardiovascular magnetic resonance and explore the prevalence and prognostic significance of RVSD in HC patients. A total of 226 patients with HC assessed by cardiovascular magnetic resonance were included in this retrospective study. RVSD was defined by RV ejection fraction (RVEF) ≤45% and was present in 26 (11.5%) patients. Association between RVSD, clinical characteristics, and outcomes were analyzed. RVEF was significantly lower in patients with RVSD than without RVSD (36.2 ± 7.0% vs 60.5 ± 7.4%, p < 0.001). There was a positive correlation between RVEF and left ventricular ejection fraction (r = 0.45; p < 0.001). During a mean follow-up of 30.5 ± 23.9 months, there were 22 (9.7 %) all-cause mortality, including 12 (5.3%) cardiovascular death. Kaplan-Meier analysis showed a significantly higher risk for cardiovascular mortality in patients with RVSD (p = 0.026), but no significant difference in all-cause mortality (p = 0.118) and heart failure related rehospitalization (p = 0.485). On multivariate Cox regression analysis, RVSD (hazard ratio 5.36; confidence interval 1.39 to 20.77; p = 0.015) and RVEF (hazard ratio 0.94; confidence interval 0.89 to 0.98; p = 0.011) were independent predictors of cardiovascular mortality. In conclusion, RVSD is a common phenotype and a strong independent predictor of cardiovascular mortality in HC patients.

Assessment of right ventricular function by echocardiography in patients with chronic heart failure

Background

The main focus of most of the studies in heart failure (HF) is the assessment of the left ventricular functions, while the right ventricle was much less studied. Much of this neglect is due to the complexity of anatomy and physiology of the right ventricle which are considered challenges during assessment of RV.

Objective

[1] To review the alterations of right ventricular dimensions & function associated with chronic heart failure. [2] To predict the prevalence of right ventricular systolic dysfunction in patients with chronic heart failure, based on echocardiographic parameters.

Methods

100 chronic left sided heart failure patients with LVEF less than 40% were evaluated in Ain Shams University hospitals from April 2015 to March 2016. All patients were subjected to full history taking & clinical evaluation. ECG was done mainly to exclude presence of ischemic heart disease. Complete trans-thoracic echocardiography study was done for assessment of [B] Left ventricular dimensions, systolic and diastolic functions [B] Assessment of the right side of the heart: [1] Measurement of the right ventricular dimensions [basal – mid cavity and the longitudinal diameters]. [2] Right ventricular area and calculation of the fractional area change (FAC). [3] Tricuspid annular plane systolic excursion (TAPSE). [4] Tissue Doppler derived tricuspid lateral annular systolic velocity (S′ wave velocity). [5] Tissue Doppler derived Myocardial Performance Index (MPI) (Tei index). [6] Grading of tricuspid regurgitation severity, and assessment of right ventricular systolic pressure.

Results

Right ventricle was dilated at the basal level in 36% of the studied patients & at the mid cavity level in 23% of the patients. Longitudinal RV diameter was enlarged in 20% of the patients.

Right ventricular systolic dysfunction was found in 36% of patients with DCM in the current study. Patients who had right ventricular systolic dysfunction had significantly higher incidence of elevated JVP, significantly lower EF and significantly higher grade of LV Diastolic dysfunction. They showed significantly larger RV dimensions at different levels, significantly worse degree of TR and significantly higher mean value of RVSP.

Conclusions

The occurrence of right ventricular systolic dysfunction in patients with DCM is common [Approaching 40% in this study] and is independent of age and sex, and is proportionate to the degree of LV dilatation, and EF impairment.

Pulmonary hypertension due to left heart disease

Pulmonary hypertension due to left heart disease, also known as group 2 pulmonary hypertension according to the European Society of Cardiology/European Respiratory Society classification, is the most common cause of pulmonary hypertension. In patients with left heart disease, the development of pulmonary hypertension favours right heart dysfunction, which has a major impact on disease severity and outcome. Over the past few years, this condition has been considered more frequently. However, epidemiological studies of group 2 pulmonary hypertension are less exhaustive than studies of other causes of pulmonary hypertension. In group 2 patients, pulmonary hypertension may be caused by an isolated increase in left-sided filling pressures or by a combination of this condition with increased pulmonary vascular resistance, with an abnormally high pressure gradient between arteries and pulmonary veins. A better understanding of the conditions underlying pulmonary hypertension is of key importance to establish a comprehensive diagnosis, leading to an adapted treatment to reduce heart failure morbidity and mortality. In this review, epidemiology, mechanisms and diagnostic approaches are reviewed; then, treatment options and future approaches are considered.

Quantification of systemic right ventricle by echocardiography

Improvements in cardiac imaging have recently focused a great interest on the right ventricle (RV). In patients with congenital heart disease, the right ventricle (RV) may support the systemic circulation (systemic RV). There are 2 different anatomic conditions providing such physiology: the congenitally corrected transposition of the great arteries (ccTGA) and the TGA surgically corrected by atrial switch. During the last decades, evidence is accumulating that progressive systemic RV failure develops leading to considerable morbidity and mortality. Various imaging modalities have been used to evaluate the systemic RV, but echocardiography is still predominantly used in clinical practice, allowing an anatomic and functional approach of the systemic RV function and the potential associated anomalies. The goal of this review is to offer a clinical perspective of the non-invasive evaluation of the systemic RV by echocardiography.

A Hybrid Method for Endocardial Contour Extraction of Right Ventricle in 4-Slices from 3D Echocardiography Dataset

This paper presents a hybrid method to extract endocardial contour of the right ventricular (RV) in 4-slices from 3D echocardiography dataset. The overall framework comprises four processing phases. In Phase I, the region of interest (ROI) is identified by estimating the cavity boundary. Speckle noise reduction and contrast enhancement were implemented in Phase II as preprocessing tasks. In Phase III, the RV cavity region was segmented by generating intensity threshold which was used for once for all frames. Finally, Phase IV is proposed to extract the RV endocardial contour in a complete cardiac cycle using a combination of shape-based contour detection and improved radial search algorithm. The proposed method was applied to 16 datasets of 3D echocardiography encompassing the RV in long-axis view. The accuracy of experimental results obtained by the proposed method was evaluated qualitatively and quantitatively. It has been done by comparing the segmentation results of RV cavity based on endocardial contour extraction with the ground truth. The comparative analysis results show that the proposed method performs efficiently in all datasets with overall performance of 95% and the root mean square distances (RMSD) measure in terms of mean ± SD was found to be 2.21 ± 0.35 mm for RV endocardial contours.

Evaluation of cardiac function index as measured by transpulmonary thermodilution as an indicator of left ventricular ejection fraction in cardiogenic shock

Introduction. The PiCCO transpulmonary thermodilution technique provides two indices of cardiac systolic function, the cardiac function index (CFI) and the global ejection fraction (GEF). Both appear to be correlated with left ventricular ejection fraction (LVEF) measured by echocardiography in patients with circulatory failure, especially in septic shock. The aim of the present study was to test the reliability of CFI as an indicator of LVEF in patients with cardiogenic shock. Methods. In thirty-five patients with cardiogenic shock, we performed (i) simultaneous measurements of echocardiography LVEF and cardiac function index assessed by transpulmonary thermodilution (n = 72) and (ii) transpulmonary thermodilution before/after increasing inotropic agents (n = 18). Results. Mean LVEF was 31% (+/−11.7), CFI 3/min (+/−1), and GEF 14.2% (+/−6). CFI and GEF were both positively correlated with LVEF (P < 0.0001, r² = 0.27). CFI and GEF were significantly increased with inotropic infusion (resp., P = 0.005, P = 0.007). A cardiac function index <3.47/min predicted a left ventricular ejection fraction ≤35% (sensitivity 81.1% and specificity 63%). In patients with right ventricular dysfunction, CFI was not correlated with LVEF. Conclusion. CFI is correlated with LVEF provided that patient does not present severe right ventricular dysfunction. Thus, the PiCCO transpulmonary thermodilution technique is useful for the monitoring of inotropic therapy during cardiogenic shock.

Longitudinal myocardial peak velocities using high temporal resolution phase-contrast and simple averaging are comparable to tissue Doppler echocardiography

OBJECT

Phase contrast imaging is widely used to measure blood velocity. However tissue Doppler imaging (TDI) echocardiography is the reference for myocardial velocity assessment. This study aims at validating the ability of phase contrast (PC) sequences to correctly assess myocardial velocities and to compare these velocities to TDI. The phase contrast sequence was performed with breath-hold parameters and with parameters tuned to increase temporal resolution in free breathing.

MATERIALS AND METHODS

Left and Right auriculo-ventricular annuluses longitudinal velocities were recorded on six healthy volunteers with different temporal resolutions (TDI: 5 ms, breath-hold PC: 94 ms and free-breathing PC: 19 ms). Free-breathing PC was obtained by averaging of three excitations. Amplitudes of four standard echocardiographic and clinically relevant myocardial longitudinal velocity waves were compared: Early filling and auricular, systolic and isovolumic contractions.

RESULTS

Isovolumic contraction waves were only visible with free-breathing PC and TDI. The differences with the reference TDI wave velocities were lower (p = 0.02) for free-breathing PC (19.2 ± 2.6%) than for breath-hold PC (28.1 ± 2.9%). These differences for free-breathing PC were close to (p = 0.21) the coefficient of variation of the measurements provided by TDI (14.8 ± 1.2%).

CONCLUSION

Myocardial longitudinal peak velocities can be assessed with a PC sequence tuned to optimize temporal resolution.

The prevalence and prognostic significance of right ventricular systolic dysfunction in nonischemic dilated cardiomyopathy

BACKGROUND

Cardiovascular magnetic resonance is the gold-standard technique for the assessment of ventricular function. Although left ventricular volumes and ejection fraction are strong predictors of outcome in dilated cardiomyopathy (DCM), there are limited data regarding the prognostic significance of right ventricular (RV) systolic dysfunction (RVSD). We investigated whether cardiovascular magnetic resonance assessment of RV function has prognostic value in DCM.

METHODS AND RESULTS

We prospectively studied 250 consecutive DCM patients with the use of cardiovascular magnetic resonance. RVSD, defined by RV ejection fraction≤45%, was present in 86 (34%) patients. During a median follow-up period of 6.8 years, there were 52 deaths, and 7 patients underwent cardiac transplantation. The primary end point of all-cause mortality or cardiac transplantation was reached by 42 of 86 patients with RVSD and 17 of 164 patients without RVSD (49% versus 10%; hazard ratio, 5.90; 95% confidence interval [CI], 3.35-10.37; P<0.001). On multivariable analysis, RVSD remained a significant independent predictor of the primary end point (hazard ratio, 3.90; 95% CI, 2.16-7.04; P<0.001), as well as secondary outcomes of cardiovascular mortality or cardiac transplantation (hazard ratio, 3.35; 95% CI, 1.76-6.39; P<0.001), and heart failure death, heart failure hospitalization, or cardiac transplantation (hazard ratio, 2.70; 95% CI, 1.32-5.51; P=0.006). Assessment of RVSD improved risk stratification for all-cause mortality or cardiac transplantation (net reclassification improvement, 0.31; 95% CI 0.10-0.53; P=0.001).

CONCLUSIONS

RVSD is a powerful, independent predictor of transplant-free survival and adverse heart failure outcomes in DCM. Cardiovascular magnetic resonance assessment of RV function is important in the evaluation and risk stratification of DCM patients.

Surface-length index: a novel index for rapid detection of right ventricles with abnormal ejection fraction using cardiac MRI

OBJECTIVE

To validate a new index, the surface-length index (SLI) based on area change in a short-axis view and length reduction in the horizontal long-axis view, which is used to quickly (<1 min) detect right ventricles with an abnormal ejection fraction (EF) during a cardiac MRI examination. SLI can be used to avoid a complete delineation of the endocardial contours of normal right ventricles.

METHODS

Sixty patients (group A) were retrospectively included to calibrate the SLI formula by optimisation of the area under the ROC curves and SLI thresholds were chosen to obtain 100 % sensitivity. Another 340 patients (group B) were prospectively recruited to test SLI's capacity to detect right ventricles (RVs) with an abnormal EF (<0.5).

RESULTS

The appropriate threshold to obtain 100 % sensitivity in group A was 0.58. In group B, with the 0.58 threshold, SLI yielded a sensitivity of 100 % and specificity of 51 %. SLI would have saved 35 % of the RV studies in our population, without inducing any diagnostic error. SLI and EF correlation was good (r (2) = 0.64).

CONCLUSION

SLI combines two simple RV measures, and brings significant improvement in post-processing efficiency by preselecting RVs that require a complete study.

KEY POINTS

• Assessment of right ventricle ejection fraction (RVEF) with cine-MRI is time consuming. • Therefore, RVEF is not always assessed during cardiac MRI. • Surface-length index (SLI) allows rapid detection of abnormal RVEF during cardiac MRI. • SLI saves one third of the operator time. • Every cardiac MRI could include RVEF assessment by means of SLI.

Routine Chest X-ray: Still Valuable for the Assessment of Left Ventricular Size and Function in the Era of Super Machines?

Objectives:

The development of technologically advanced, expensive techniques has progressively reduced the value of chest X-ray in clinical practice for the assessment of left ventricular (LV) dilatation and dysfunction. Although controversial data are reported on the role of this widely available technique in cardiac assessment, it is known that the cardio-thoracic ratio is predictive of risk of progression in the NYHA Class, hospitalization, and outcome in patients with LV dysfunction. This study aimed to evaluate the reliability of the transverse diameter of heart shadow [TDH] by chest X-ray for detecting LV dilatation and dysfunction as compared to Magnetic Resonance Imaging (MRI) performed for different clinical reasons.

Materials and Methods:

In 101 patients, TDH was measured in digital chest X-ray and LV volumes and ejection fraction (EF) by MRI, both exams performed within 2 days.

Results:

A direct correlation between TDH and end-diastolic volumes (r = .75, P<0.0001) was reported. TDH cut-off values of 14.5 mm in females identified LV end-diastolic volumes >150 mL (sensitivity: 82%, specificity: 69%); in males a cut-off value of 15.5 mm identified LV end-diastolic volumes >210 mL (sensitivity: 84%; specificity: 72%). A negative relation was found between TDH and LVEF (r = -.54, P<0.0001). The above cut-off values of TDH discriminated patients with LV systolic dysfunction – LVEF <35% (sensitivity and specificity: 67% and 57% in females; 76% and 59% in males, respectively).

Conclusions:

Chest X-ray may still be considered a reliable technique in predicting LV dilatation by the accurate measurement of TDH as compared to cardiac MRI. Technologically advanced, expensive, and less available imaging techniques should be performed on the basis of sound clinical requests.

Predictors of right ventricle dysfunction after anterior myocardial infarction

BACKGROUND

Regardless significant therapeutic advances, mortality and morbidity after myocardial infarction (MI) are still high. For a long time, the importance of right ventricle (RV) function has been neglected. Recently, RV dysfunction has also been associated with poor outcomes in the setting of heart failure. The shape, location, and contraction conditions make the RV chamber assessment technically challenging.

METHODS

Our study identified clinical characteristics and left ventricle (LV) echocardiographic data performed 3-5 days after MI that could be associated with RV dysfunction (RV fractional area change [FAC] < 35%) 6 months after MI.

RESULTS

The RV dysfunction group consisted of 11 patients (RV FAC 29.4% ± 5.2) and the no RV dysfunction group of 71 patients (RV FAC 43.7% ± 5.1); (P < 0.001). Both groups presented the same baseline clinical characteristics. Left atrium (LA), interventricular septum (IVS), and left ventricular posterior wall (LVPW) were larger in RV dysfunction than in no RV dysfunction. Conversely, E wave deceleration time (EDT) was lower in RV dysfunction when compared with no RV dysfunction. Left atrium(adj) (adjusted by gender, age, infarct size, and body mass index) (odds ratio [OR], 1.22; confidence interval [CI], 1.016-1.47; P = 0.032), interventricular septum(adj) (OR, 1.49; CI, 1.01-2.23; P = 0.044), and E wave deceleration time(adj) (OR, 0.98; CI, 0.97-0.98; P = 0.029) assessed soon after MI predicted RV failure after 6-months.

CONCLUSIONS

LV diastolic dysfunction, resulting from anterior MI and assessed 3-5 days after the event, may play an important role in predicting RV dysfunction 6 months later.

4-D blood flow in the human right ventricle

Right ventricular (RV) function is a powerful prognostic indicator in many forms of heart disease, but its assessment remains challenging and inexact. RV dysfunction may alter the normal patterns of RV blood flow, but those patterns have been incompletely characterized. We hypothesized that, based on anatomic differences, the proportions and energetics of RV flow components would differ from those identified in the left ventricle (LV) and that the portion of the RV inflow passing directly to outflow ( Direct Flow) would be prepared for effective systolic ejection as a result of preserved kinetic energy (KE) compared with other RV flow components. Three-dimensional, time-resolved phase-contrast velocity, and balanced steady-state free-precession morphological data were acquired in 10 healthy subjects using MRI. A previously validated method was used to separate the RV and LV end-diastolic volumes into four flow components and measure their volume and KE over the cardiac cycle. The RV Direct Flow: 1) followed a smoothly curving route that did not extend into the apical region of the ventricle; 2) had a larger volume and possessed a larger presystolic KE (0.4 ± 0.3 mJ) than the other flow components ( P < 0.001 and P < 0.01, respectively); and 3) represented a larger part of the end-diastolic blood volume compared with the LV Direct Flow ( P < 0.01). These findings suggest that diastolic flow patterns distinct to the normal RV create favorable conditions for ensuing systolic ejection of the Direct Flow component. These flow-specific aspects of RV diastolic-systolic coupling provide novel perspectives on RV physiology and may add to the understanding of RV pathophysiology.