Echocardiographic assessment of the right ventricle: Impact of the distinctly load dependency of its size, geometry and performance

Echocardiographic assessment of right ventricular function and right ventriculoarterial coupling in tricuspid regurgitation

Echocardiographic evaluation of the cardiopulmonary unit is difficult in case of tricuspid regurgitation (TR) and combined echocardiographic parameters could be useful. This study aimed to assess the variation of simple and combined echocardiographic parameters analysing the cardiopulmonary unit according to the severity of TR. TR was graded according to Hahn's classification in 179 patients. Classical morphological, function and load parameters analysing right ventricle were assessed. Combined parameters of function and load; morphology and load; and morphology-load-function index were calculated. We used ROC curve analysis to analyze the diagnostic value of echocardiographic parameters to predict potential high or low surgical risk of mortality according to TRISCORE in 82 patients. Simple parameters were significatively different among groups with a nonlinear progression between the 5 levels of severity of TR. Combined parameters were also significatively different among groups. Among them, myomechanical index (MMI = RV-RA mean pressure gradient x RVFWS/indexed RAED area × 10-2) and morphology-load-function index (MLF = RVED length/area x TR TVI x RVFWS) had a linear progression between the 5 groups and had the best predictive value for TRISCORE high and low risk. Combined parameters are relevant to evaluate cardiopulmonary unit in patients with various degrees of TR, especially when combining morphology, function, and load parameters, and are potentially interesting in their prognostic assessment, as shown by the good predictive value for TRISCORE risk.

Prognostic value of right ventricular dysfunction in aortic regurgitation after transcatheter aortic valve replacement

Background

Aortic regurgitation (AR) may lead to right ventricular dysfunction (RVD), but the prognostic value of RVD in patients undergoing transcatheter aortic valve replacement (TAVR) remains unclear. Our goal was to evaluate the clinical implications, predictors and prognostic significance of RVD in patients with pure AR after TAVR.

Methods

In this multicentre prospective study, patients undergoing TAVR were included between January 2019 and April 2021. The patients were divided into four groups according to the results of transthoracic echocardiography pre- and post-TAVR. The primary end point was 2-year all-cause mortality.

Results

A total of 648 patients were divided into four groups: 325 patients (54.3%) in the no RVD group; 106 patients (17.7%) in the new-onset RVD group; 73 patients (12.2%) in the normalized RVD group; and 94 patients (15.7%) in the residual RVD group. At the 2-year follow-up, there were significant differences in all-cause mortality among the four groups (5.2%, 12.3%, 11.0% and 17.0%, respectively; p < 0.05). New-onset RVD was correlated with an increased risk of all-cause death and a composite end point and normalized RVD improved clinical outcomes of baseline RVD. Predictors of new-onset RVD included a higher Society of Thoracic Surgeons score, larger left ventricular end-diastolic volume, lower left ventricular ejection fraction, higher systolic pulmonary artery pressure and smaller RV base diameter.

Conclusions

Changes in periprocedural RVD status significantly affect the risk stratification outcomes after TAVR. Therefore, they may be used as part of decision-making and risk assessment strategies.

Clinical Trial Registration

ClinicalTrials.gov Protocol Registration System (NCT02917980).

Right Ventricular Dysfunction on Transthoracic Echocardiography and Long-Term Mortality in the Critically Unwell: A Systematic Review and Meta-Analysis

OBJECTIVE

Right ventricular dysfunction (RVD) is common in the critically ill. To date studies exploring RVD sequelae have had heterogenous definitions and diagnostic methods, with limited follow-up. Additionally much literature has been pathology specific, limiting applicability to the general critically unwell patient.

METHOD AND STUDY DESIGN

We conducted a systematic review and meta-analysis to evaluate the impact of RVD diagnosed with transthoracic echocardiography (TTE) on long-term mortality in unselected critically unwell patients compared to those without RVD. A systematic search of EMBASE, Medline and Cochrane was performed from inception to March 2022. All RVD definitions using TTE were included. Patients were those admitted to a critical or intensive care unit, irrespective of disease processes. Long-term mortality was defined as all-cause mortality occurring at least 30 days after hospital admission. A priori subgroup analyses included disease specific and delayed mortality (death after hospital discharge/after the 30th day from hospital admission) in patients with RVD. A random effects model analysis was performed with the Dersimionian and Laird inverse variance method to generate effect estimates.

RESULTS

Of 5985 studies, 123 underwent full text review with 16 included (n = 3196). 1258 patients had RVD. 19 unique RVD criteria were identified. The odds ratio (OR) for long term mortality with RVD was 2.92 (95% CI 1.92-4.54, I2 76.4%) compared to no RVD. The direction and extent was similar for cardiac and COVID19 subgroups. Isolated RVD showed an increased risk of delayed mortality when compared to isolated left/biventricular dysfunction (OR 2.01, 95% CI 1.05-3.86, I2 46.8%).

CONCLUSION

RVD, irrespective of cause, is associated with increased long term mortality in the critically ill. Future studies should be aimed at understanding the pathophysiological mechanisms by which this occurs. Commonly used echocardiographic definitions of RVD show significant heterogeneity across studies, which contributes to uncertainty within this dataset.

How Would We Treat Our Own Cystic Fibrosis With Lung Transplantation?

Lung transplantation is the only therapy for patients with end-stage lung disease. In advanced lung diseases such as cystic fibrosis (CF), life expectancy increases, and it is important to recognize extrapulmonary comorbidities. Cardiovascular involvement, including pulmonary hypertension, right-heart failure, and myocardial dysfunction, are manifest in the late stages of CF disease. Besides right-heart failure, left-heart dysfunction seems to be underestimated. Therefore, an optimal anesthesia and surgical management risk evaluation in this high-risk patient population is mandatory, especially concerning the perioperative use of mechanical circulatory support. The use of an index case of an older patient with the diagnosis of cystic fibrosis demonstrates the importance of early risk stratification and strategy planning in a multidisciplinary team approach to guarantee successful lung transplantation.

Pulmonary Vascular Resistance to Predict Right Heart Failure in Patients Undergoing Left Ventricular Assist Device Implantation

Right heart failure (RHF) is associated with poor outcomes, especially in patients undergoing left ventricular assist device (LVAD) implantation. The aim of this study was to identify predictors of RHF after LVAD implantation. Of 129 consecutive patients (mean age 56 ± 11 years, 89% male) undergoing LVAD implantation, 34 developed RHF. Compared to patients without RHF, those with RHF required longer invasive mechanical ventilation and had longer intensive care unit and hospital stays (p < 0.01). One-year all-cause mortality was significantly higher in patients with versus without RHF after LVAD implantation (29.4% vs. 1.2%; hazard ratio 35.4; 95% confidence interval 4.5-277; p < 0.001). Mortality was highest in patients with delayed RHF after initial LVAD-only implantation (66.7%). Patients who did versus did not develop RHF had significantly higher baseline pulmonary vascular resistance (PVR; 404 ± 375 vs. 234 ± 162 dyn/s/cm5; p = 0.01). PVR > 250 dyn/s/cm5 was a significant predictor of survival in patients with RHF after LVAD implantation. These data confirm the negative impact of RHF on morbidity and mortality after LVAD implantation. Preoperative PVR > 250 dyn/s/cm5 determined using invasive right heart catheterization was an independent predictor of developing RHF after LVAD implantation, and of subsequent mortality, and could be used for risk stratification in the setting for deciding between single or biventricular support strategy.

Multiparametric assessment of right ventricular function in heart transplant recipients by echocardiography and relations with pulmonary hemodynamics

OBJECTIVE

Right ventricular (RV) dilatation and dysfunction are usually present in heart transplant (HTx) patients and worsened with residual pulmonary hypertension (PH). We aimed to determine the ability of different echocardiographic modalities to evaluate RV function in comparison with cardiac magnetic resonance (CMR) and their relations with pulmonary hemodynamics in HTx patients.

METHODS

A total of 62 data sets [echocardiographic, hemodynamic, and CMR] were acquired from 35 HTx patients. Comprehensive echocardiography, including two-dimensional (2D) transthoracic echocardiography, speckle tracking echocardiography, and three-dimensional (3D) echocardiography, was performed. Mean pulmonary artery pressure (mPAP) was obtained invasively from right heart catheterization. The correlations between all echocardiographic parameters and CMR imaging data and the differences between patients with and without residual PH were evaluated.

RESULTS

Diastolic and systolic RV volumes and RV ejection fraction (RVEF) by 3D echocardiography correlated strongly with CMR-derived volumes and RVEF (r = .91, r = .79, r = .64; p < .0001 for each, respectively). Among other parameters, RV fractional area change (r = .439; p < .001) and RV free wall longitudinal strain (RVFW-LS) (r = -.34; p < .05) correlated moderately with CMR-RVEF, whereas tricuspid annulus S' velocity (r = .29; p < .05) and tricuspid annular systolic plane excursion (r = .27; p < .05) correlated weakly with CMR-RVEF. Additionally, 3D-RVEF and RVFW-LS were significantly decreased in studies with mPAP ≥ 20 mm Hg in comparison to those with mPAP < 20 mm Hg (47.7 ± 3.7 vs. 50.9 ± 5.3, p = .04 and -15.5 ± 3.1 vs. -17.5 ± 3, p = .03, respectively).

CONCLUSION

The best method for the evaluation of RV function in HTx recipients is 3D echocardiography. Besides, the subclinical impact of residual PH on RV function can be best determined by RVFW-LS and 3D-RVEF in these patients.

The relation of right ventricular outflow tract measurements with in-hospital clinical outcomes after tricuspid valve surgery

Right ventricular (RV) function is a determining factor for clinical outcomes in patients undergoing tricuspid valve surgery (TVS). Our aim was to investigate the importance of the function of the right ventricular outflow tract (RVOT), which is an important anatomical region of the RV, in patients underwent TVS. 104 patients who underwent TVS were analyzed retrospectively. Patients with previous cardiac surgery, congenital heart disease, or heart failure were excluded. The parasternal short-axis view at the level of the aortic root was used to measure RVOT dimensions and RVOT fractional shortening (RVOT-FS). The effect of RVOT diameter and function on major adverse cardiac events (MACE) after TVS was investigated. In our study, MACE, consisting of pacemaker implantation, acute kidney injury, postoperative atrial fibrillation and mortality, was developed at 44 (42.3%) patients.We compared the predictive performances of RVOT end-systolic (RVOTs) diameter, RVOT end-diastolic (RVOTd) diameter, RVOT-FS and RV diameters in prediction of MACE. The model including the RVOTs had higher AUC, R2 and likelihood ratio X2 values (0.775, 0.287 and 25.0, respectively) than RVOTd (0.770, 0.279 and 24.2, respectively) and RVOT-FS (0.750, 0.215 and 18.1, respectively). RVOT diameters showed better performance in predicting MACE than RV diameters. Moreover, there was statistically significant association between RVOTs, RVOTd and MACE (p value were 0.014 and 0.027, respectively), while no association between RVOT-FS and MACE (p value was 0.177). In summary, we determined that the RVOT diameters are important predictors for the in-hospital clinical outcomes of patients who underwent TVS.

Evaluation of right-ventricular function by two-dimensional echocardiography and two-dimensional speckle-tracking echocardiography in patients with successful RCA CTO recanalization

OBJECTIVES

Chronic total occlusion (CTO) of the right coronary artery (RCA) is common in patients with coronary artery disease. Although revascularization techniques and success rates have improved significantly in recent years, there are still no studies investigating possible effects of successful recanalization of RCA CTO on the right-ventricular (RV) function. With this study, we aimed to evaluate RV function after recanalization of the RCA by two-dimensional transthoracic echocardiography (2DE) and additional two-dimensional speckle-tracking echocardiography (2DSTE).

METHODS AND RESULTS

Our analysis included 102 patients undergoing successful RCA CTO recanalization at the University Medical Center of Mainz. All patients underwent 2DE and 2DSTE to assess RV function before PCI procedure and 6 months after successful revascularization. We found an altered RV function in our collective at baseline assessed by 2DSTE with a significant improvement at 6 month follow-up (baseline RV free wall strain: - 20.7 [- 6.3 to - 32.0] % vs. - 23.4 [- 8.3 to - 39.3] % at follow-up, p < 0.001 and baseline RV global strain - 15.9 [- 6.0 to - 25.7] % vs. - 17.9 [- 7.0 to - 29.5] % at follow-up, p < 0.001).

CONCLUSION

RV function was altered in patients with RCA CTO and showed significant improvement after successful recanalization. We also noticed an improvement in patient-reported clinical symptoms. Our study suggests that CTO procedure is a beneficial treatment option in symptomatic patients with RCA CTO.

Prognosis of Right Ventricular Systolic Dysfunction in Patients With Duchenne Muscular Dystrophy

Background Chronic respiratory failure and heart involvement may occur in Duchenne muscular dystrophy. We aimed to assess the prognostic value of the right ventricular (RV) systolic dysfunction in patients with Duchenne muscular dystrophy. Methods and Results We studied 90 genetically proven patients with Duchenne muscular dystrophy from 2010 to 2019, to obtain respiratory function and Doppler echocardiographic RV systolic function. Prognostic value was assessed in terms of death and cardiac events. The median age was 27.5 years, and median forced vital capacity was at 10% of the predicted value: 83 patients (92%) were on home mechanical ventilation. An RV systolic dysfunction was found in 46 patients (51%). In patients without RV dysfunction at inclusion, a left ventricular systolic dysfunction at inclusion was associated with a higher risk of developing RV dysfunction during follow-up with an odds ratio of 4.5 (P=0.03). RV systolic dysfunction was significantly associated with cardiac events, mainly acute heart failure (62%) and cardiogenic shock (23%). In a multivariable Cox model, the adjusted hazard ratio was 4.96 (95% CI [1.09-22.6]; P=0.04). In terms of death, we found a significant difference between patients with RV dysfunction versus patients without RV dysfunction in the Kaplan-Meier curves (log-rank P=0.045). Conclusions RV systolic dysfunction is frequently present in patients with Duchenne muscular dystrophy and is associated with increased risk of cardiac events, irrespective of left ventricular dysfunction and mechanical ventilation. Registration URL: https://www.clinicaltrials.org; unique identifier: NCT02501083.

Cellular and Molecular Mechanisms Underlying Tricuspid Valve Development and Disease

Tricuspid valve (TV) disease is highly prevalent in the general population. For ages considered "the forgotten valve" because of the predominant interest in left-side valve disease, the TV has now received significant attention in recent years, with significant improvement both in diagnosis and in management of tricuspid disease. TV is characterized by complex anatomy, physiology, and pathophysiology, in which the right ventricle plays a fundamental role. Comprehensive knowledge of molecular and cellular mechanisms underlying TV development, TV disease, and tricuspid regurgitation-related right-ventricle cardiomyopathy is necessary to enhance TV disease understanding to improve the ability to risk stratify TR patients, while also predicting valve dysfunction and/or response to tricuspid regurgitation treatment. Scientific efforts are still needed to eventually decipher the complete picture describing the etiopathogenesis of TV and TV-associated cardiomyopathy, and future advances to this aim may be achieved by combining emerging diagnostic imaging modalities with molecular and cellular studies. Overall, basic science studies could help to streamline a new coherent hypothesis underlying both the development of TV during embryogenesis and TV-associated disease and its complications in adult life, providing the conceptual basis for the ultimate and innovative field of valve repair and regeneration using tissue-engineered heart valves.

The Role of Transthoracic Echocardiography for Assessment of Mortality in Patients with Carcinoid Heart Disease Undergoing Valve Replacement

Patients with carcinoid heart disease (CHD) are referred for valve replacement if they have severe symptomatic disease or evidence of right ventricular (RV) failure and an anticipated survival of at least 12 months. Data are lacking, however, on the role of transthoracic echocardiography in predicting outcomes. We carried out a retrospective, single-centre cohort study of patients with a biopsy-confirmed neuroendocrine tumour (NET) and CHD undergoing valve replacement for severe valve disease and symptoms of right heart failure. The aim was to identify factors associated with postoperative mortality, both within one year of surgery and during long-term follow-up. Of 88 patients with NET, 49 were treated surgically (mean age: 64.4 ± 7.6 years; 55% male), of whom 48 had a bioprosthetic tricuspid valve replacement for severe tricuspid regurgitation; 39 patients had a pulmonary valve replacement. Over a median potential follow-up of 96 months (interquartile range: 56-125), there were 37 deaths, with 30-day and one-year mortality of 14% (n = 7) and 39% (n = 19), respectively. A significant relationship between RV size and one-year mortality was observed, with 57% of those with severe RV dilatation dying within a year of surgery, compared to 33% in those with normal RV size (p = 0.039). This difference remained significant in the time-to-event analysis of long-term survival (p = 0.008). RV size was found to reduce significantly with surgery (p < 0.001). Those with persisting RV dilatation (p = 0.007) or worse RV function (p = 0.001) on postoperative echocardiography had significantly shorter long-term survival. In this single-centre retrospective study of patients undergoing surgery for CHD, increasingly severe RV dilatation on preoperative echocardiography predicted adverse outcomes, yielding a doubling of the one-year mortality rate relative to normal RV size. These data support the possibility that early surgery might deliver greater long-term benefits in this patient cohort.

The Dysfunctional Right Ventricle in Dilated Cardiomyopathies: Looking from the Right Point of View

Dilated cardiomyopathies (DCMs) are a heterogenous group of primary myocardial diseases, representing one of the leading causes of heart failure, and the main indication for heart transplantation. While the degree of left ventricular dilation and dysfunction are two key determinants of adverse outcomes in DCM patients, right ventricular (RV) remodeling and dysfunction further negatively influence patient prognosis. Consequently, RV functional assessment and diagnosing RV involvement by using an integrative approach based on multimodality imaging is of paramount importance in the evaluation of DCM patients and provides incremental prognostic and therapeutic information. Transthoracic echocardiography remains the first-line imaging modality used for the assessment of the RV, and newer techniques such as speckle-tracking and three-dimensional echocardiography significantly improve its diagnostic and prognostic accuracy. Nonetheless, cardiac magnetic resonance (CMR) is considered the gold standard imaging modality for the evaluation of RV size and function, and all DCM patients should be evaluated by CMR at least once. Accordingly, this review provides a comprehensive overview of the anatomy and function of the RV, and the pathophysiology, diagnosis, and prognostic value of RV dysfunction in DCM patients, based on traditional and novel imaging techniques.

Right ventricular strain measurements in critically ill patients: an observational SICS sub-study

BACKGROUND

Right ventricular (RV) dysfunction is common in critically ill patients and is associated with poor outcomes. RV function is usually evaluated by Tricuspid Annular Plane Systolic Excursion (TAPSE) which can be obtained using critical care echocardiography (CCE). Myocardial deformation imaging, measuring strain, is suitable for advanced RV function assessment and has widely been studied in cardiology. However, it is relatively new for the Intensive Care Unit (ICU) and little is known about RV strain in critically ill patients. Therefore, the objectives of this study were to evaluate the feasibility of RV strain in critically ill patients using tissue-Doppler imaging (TDI) and explore the association between RV strain and conventional CCE measurements representing RV function.

METHODS

This is a single-center sub-study of two prospective observational cohorts (Simple Intensive Care Studies (SICS)-I and SICS-II). All acutely admitted adults with an expected ICU stay over 24 h were included. CCE was performed within 24 h of ICU admission. In patients in which CCE was performed, TAPSE, peak systolic velocity at the tricuspid annulus (RV s') and TDI images were obtained. RV free wall longitudinal strain (RVFWSL) and RV global four-chamber longitudinal strain (RV4CSL) were measured during offline analysis.

RESULTS

A total of 171 patients were included. Feasibility of RVFWSL and RV4CSL was, respectively, 62% and 56% in our population; however, when measurements were performed, intra- and inter-rater reliability based on the intraclass correlation coefficient were good to excellent. RV dysfunction based on TAPSE or RV s' was found in 56 patients (33%) and 24 patients (14%) had RV dysfunction based on RVFWSL or RV4CSL. In 14 patients (8%), RVFWSL, RV4CSL, or both were reduced, despite conventional RV function measurements being preserved. These patients had significantly higher severity of illness scores. Sensitivity analysis with fractional area change showed similar results.

CONCLUSIONS

TDI RV strain imaging in critically ill patients is challenging; however, good-to-excellent reproducibility was shown when measurements were adequately obtained. Future studies are needed to elucidate the diagnostic and prognostic value of RV strain in critically ill patients, especially to outweigh the difficulty and effort of imaging against the clinical value.

Right and left ventricular structures and functions in acute HFpEF: comparing the hypertensive pulmonary edema and worsening heart failure phenotypes

BACKGROUND

Limited data are available on right (RV) and left (LV) ventricular structures and functions in acute heart failure with preserved ejection fraction (AHF-pEF) presenting with hypertensive pulmonary edema (APE) versus predominant peripheral edema (peHF).

METHODS AND RESULTS

In a prospective study of consecutive patients with AHF-pEF, 80 patients met inclusion and not exclusion criteria, and underwent echocardiographic and laboratory examination in the emergency ward. The survived (94%) were re-evaluated at the discharge. At admission, systolic, diastolic, pulse blood pressure (BP), and high sensitivity troponin I were higher (all P < 0.05) with APE than with peHF while brain-type natriuretic peptide (BNP), hemoglobin and estimated glomerular filtration rate (eGFR) did not differ between the two phenotypes. LV volumes and EF were comparable between APE and peHF, but APE showed lower relative wall thickness (RWT), smaller left atrial (LA) volume, higher pulse pressure/stroke volume (PP/SV), and higher ratio between the peak velocities of the early diastolic waves sampled by traditional and tissue Doppler modality (mitral E/e', all P < 0.05). Right ventricular and atrial (RA) areas were smaller, tricuspid anular plane systolic excursion (TAPSE) and estimated pulmonary artery peak systolic pressure (sPAP) were higher with APE than with peHF (all P < 0.05) while averaged degree of severity of tricuspid insufficiency was greater with peHF than with APE. At discharge, PP/SV, mitral E/e', sPAP, RV sizes were reduced from admission in both phenotypes (all P < 0.05) and did not differ anymore between phenotypes, whereas LV EF and TAPSE did not show significant changes over time and treatments.

CONCLUSION

In AHF-pEF, at comparable BNP and LV EF, hypertensive APE showed eccentric LV geometry but smaller RV and RA sizes, and higher RV systolic function, increased LV ventricular filling and systemic arterial loads. AHF resolution abolished the differences in PP/SV and LV diastolic load between APE and peHF whereas APE remained associated with more eccentric RV and higher TAPSE.

Correlations among noninvasive right ventricular myocardial work indices and the main parameters of systolic and diastolic functions

BACKGROUND

Right ventricular (RV) myocardial work (RVMW) is the latest method used to assess RV function. To date, correlations among RVMW indices and RV systolic and diastolic functions have not been studied.

METHODS

A total of 106 healthy volunteers (median age, 34 years; 46% male) were prospectively enrolled. RVMW indices were measured using the RV pressure-strain loop using specific software. The correlations among RVMW indices and other RV functions were analyzed.

RESULTS

During the multivariate analysis, the RV global work index (RVGWI) was significantly correlated with RV global longitudinal strain (RV GLS) (p < .0001), pulmonary systolic artery pressure (PASP) (p < .0001), and tricuspid annular (TA) plane systolic excursion (TAPSE) (p = .036). RV global constructive work (RVGCW) was correlated with RV GLS (p < .0001) and PASP (p < .0001). RV global wasted work (RVGWW) was correlated with RV GLS (p = .008) and TA isovolumetric acceleration (TA IVA) (p = .008). RV global work efficiency (RVGWE) was correlated with RV GLS (p < .0001) and tissue Doppler (TD) RV myocardial performance index (TD RMPI) (p = .043).

CONCLUSION

RVMW indices showed good correlations with RV myocardial systolic function.

Prognostic value of right ventricular remodelling in patients undergoing concomitant aortic and mitral valve surgery

AIMS

Long-term risk stratification and surgical timing remain suboptimal in concomitant aortic and mitral (double) valve surgery. This study sought to examine the predictors, changes, and prognostic implications of right ventricular (RV) remodelling in patients undergoing double-valve surgery.

METHODS AND RESULTS

In 152 patients undergoing double-valve surgery, four RV remodelling patterns were characterized using transthoracic echocardiography: normal RV size and systolic function (Pattern 1); dilated RV (tricuspid annulus diameter >35 mm) with normal systolic function (Pattern 2); normal RV size with systolic dysfunction (percentage RV fractional area change <35%; Pattern 3); and dilated RV with systolic dysfunction (Pattern 4). The primary endpoint was the composite of heart failure hospitalization and all-cause mortality. Patterns 1, 2, 3, and 4 RV remodelling were present in 41, 20, 23, and 16% of patients, respectively. Patients with Stage 4 RV remodelling had worse renal function, higher EuroSCORE II, and impaired left ventricular ejection fraction. During a 3.7-year median follow up, 45 adverse events occurred. Patterns 3 and 4 RV remodelling were associated with significantly higher adverse event rates compared with Pattern 1 (37 and 75% vs. 11%, P < 0.01) and had incremental prognostic value when added to clinical parameters and EuroSCORE II (χ2 increased from 30 to 66, P < 0.01). At 1 year after surgery (n = 100), Patterns 3 and 4 RV remodelling had a higher risk of adverse events compared with Pattern 1.

CONCLUSION

Right ventricular remodelling was strongly related to adverse outcomes and deserves consideration as part of the risk and decision-making algorithms in double-valve surgery.

Mending the Model for End-Stage Liver Disease: An in-depth review of the past, present, and future portopulmonary hypertension Model for End-Stage Liver Disease exception

Patients with portopulmonary hypertension (POPH) have an increased cardiovascular and overall mortality risk when undergoing liver transplantation (LT). However, such risk is not captured in their Model for End-Stage Liver Disease (MELD) laboratory score. POPH MELD exception criteria were established in 2006 with the aim of prioritizing these patients for LT prior to pulmonary hypertension (PH) progression and eventual right heart failure. The original criteria emphasized a posttreatment, pre-LT mean pulmonary arterial pressure (mPAP) of <35 mm Hg and pulmonary vascular resistance (PVR) <400 dynes-s-cm^-5 or <5 Wood units (WU). Since 2006, there have been important advances in the treatment of POPH with pulmonary arterial hypertension (PAH)-targeted therapies and newer evidence regarding LT outcomes and risk factors for perioperative mortality. Specifically, PVR rather than mPAP has been shown to be more strongly associated with outcomes, including mortality. In addition, among treated patients with POPH, mPAP may be persistently elevated related to an elevated cardiac output or other factors that do not necessarily reflect POPH disease severity. Thus, in February 2021, the Organ Procurement and Transplantation Network approved proposed modifications to POPH MELD exception criteria, now allowing either of the following posttreatment, pre-LT hemodynamic profiles: mPAP less than 35 mm Hg and posttreatment PVR less than 400 dynes-s-cm^-5 (or less than 5 WU) or mPAP greater than or equal to 35 mm Hg and less than 45 mm Hg and posttreatment PVR less than 240 dynes-s-cm^-5 (or less than 3 WU). This article reviews the history of the POPH MELD exception criteria, describes the recent modifications to the exception criteria and the evidence supporting them, and highlights unanswered questions and areas for future research.

RIGHT VENTRICLE FUNCTION IN PATIENTS WITH ANTERIOR MYOCARDIAL INFARCTION: ARE WE SURE IT IS NOT INVOLVED?

The right and left ventricle of heart are intimately connected by anatomical and functional links. Hence, acute changes in cardiac geometry and function can modify the performance and physiology of both sides of the heart, influencing each other. After a brief overview of the anatomy and related imaging techniques for the study of right ventricular function, we report a review on the interesting correlation of acute anterior myocardial infarction and right ventricular function, very often underestimated.

Baseline intracardiac echocardiography predicts haemodynamic changes and Doppler velocity patterns during follow-up after percutaneous pulmonary valve implantation

BACKGROUND

Intracardiac echocardiography Doppler-derived gradients have previously been shown to correlate with post-procedure echocardiographic evaluations when compared with invasive gradients measured during percutaneous pulmonary valve implantation, suggesting that intracardiac echocardiography could offer an accurate and predictable starting point to estimate valve function after percutaneous pulmonary valve implantation.

METHODS

We performed a retrospective chart review of 51 patients who underwent percutaneous pulmonary valve implantation between September 2018 and December 2019 in whom intracardiac echocardiography was performed immediately after valve implantation. We evaluated the correlation between intracardiac echocardiography gradients and post-procedural Doppler-derived gradients. Among the parameters assessed, those which demonstrated the strongest correlation were used to create a predictive model of expected echo-derived gradients after percutaneous pulmonary valve implantation. The equation was validated on the same sample data along with a subsequent cohort of 25 consecutive patients collected between January 2020 and July 2020.

RESULTS

All the assessed correlation models between intracardiac echocardiography evaluation and post-procedure transthoracic echocardiographic assessments were statistically significant, presenting moderate to strong correlations. The strongest relationship was found between intracardiac echocardiography mean gradients and post-procedural transthoracic echocardiographic mean gradients. Therefore, an equation was created based on the intracardiac echocardiography-derived mean gradient, to allow prediction of the post-procedural and follow-up transthoracic echocardiographic-derived mean gradients within a range of ±5 mmHg from the observed value in more than 80% of cases.

CONCLUSIONS

There is a strong correlation between intracardiac echocardiography and post-procedure transthoracic echocardiographic. This allowed us to derive a predictive equation that defines the expected transthoracic echocardiographic Doppler-derived gradient following the procedure and at out-patient follow-up after percutaneous pulmonary valve implantation.

Right ventricular systolic and diastolic function assessed by two-dimensional speckle tracking echocardiography in dogs with myxomatous mitral valve disease

Pulmonary hypertension (PH) is a common comorbidity in dogs with myxomatous mitral valve disease (MMVD), and can induce various changes in the right heart, such as right ventricular (RV) hypertrophy, dilatation, and dysfunction. We hypothesized that RV function, not only systolic function but also diastolic function, could be worsened with PH progression. We aimed to compare RV systolic and diastolic function in dogs with MMVD. Twenty healthy dogs and sixty-eight dogs with MMVD were enrolled. Dogs with MMVD were classified into the probability of PH. Two-dimensional and Doppler echocardiographic indices for right heart and two-dimensional speckle tracking echocardiography indices were measured. The morphological indicators of the right heart were significantly higher only in the high probability of PH group. The RV strain, early-diastolic and systolic strain rates were significantly lower in the high probability of PH group than those in the low and intermediate probability of PH groups. Multivariate analysis showed that increased RV internal dimension normalized by body weight and RV myocardial performance index were significantly associated with the presence of right-sided congestive heart failure. Speckle tracking echocardiography-derived RV systolic and diastolic function were activated in the low and intermediate probability of PH groups. However, dogs with high probability of PH showed RV myocardial dysfunction and dilatation. Increased RV myocardial performance index and end-diastolic RV internal dimension normalized by body weight were significantly associated with the presence of right-sided congestive heart failure in dogs with MMVD.

Grading right ventricular dysfunction in left ventricular disease using echocardiography: a proof of concept using a novel multiparameter strategy

Aims

Grading right ventricular dysfunction (RVD) in patients with left ventricular (LV) disease has earned little attention. In the present study, we established an echocardiographic RVD score and investigated how increments of the score correspond to RVD at right heart catheterization.

Methods and results

We included 95 patients with LV disease consecutively referred for heart transplant or heart failure work‐up with catheterization and echocardiography within 48 h. The RVD score (5 points) included well‐known characteristics of the development from compensated to decompensated right ventricular (RV) function: pulmonary hypertension, reduced RV strain, RV area dilatation, moderate/severe tricuspid regurgitation, and increased right atrial pressure (RAP) by echocardiography. Comparing three groups with increments of RVD score [1 (mild), 2–3 (moderate), and 4–5 (severe)] showed more advanced RVD with increasing RV end‐diastolic pressure (P < 0.001) and signs of uncoupling to load (reduced ratio between RV and pulmonary artery elastance, P < 0.001) and more spherical RV shape (RV area/length, P < 0.001). Receiver operating characteristic curve analysis for detection of severe RV (RAP ≥ 10 mmHg) showed for the RVD score an area under the curve of 0.88 compared with 0.69, 0.68, and 0.64 for RV strain, tricuspid annular plane systolic excursion, and fractional area change, respectively. A patient with RVD score ≥ 4 had a 6.7‐fold increase in likelihood of severe RVD, and no patient with RVD score ≤ 1 had severe RVD.

Conclusions

In this proof of concept study, a novel RVD score outperformed the widely used longitudinal parameters regarding grading of RVD severity, with a potential role for refined diagnosis, follow‐up, and prognosis assessment in heart failure patients.

Heart-lung interactions in COVID-19: prognostic impact and usefulness of bedside echocardiography for monitoring of the right ventricle involvement

Due to the SARS-CoV-2 infection–related severe pulmonary tissue damages associated with a relative specific widespread thrombotic microangiopathy, the pathophysiologic role of heart–lung interactions becomes crucial for the development and progression of right ventricular (RV) dysfunction. The high resistance in the pulmonary circulation, as a result of small vessel thrombosis and hypoxemia, is the major cause of right heart failure associated with a particularly high mortality in severe COVID-19. Timely identification of patients at high risk for RV failure, optimization of mechanical ventilation to limit its adverse effects on RV preload and afterload, avoidance of medication-related increase in the pulmonary vascular resistance, and the use of extracorporeal membrane oxygenation in refractory respiratory failure with hemodynamic instability, before RV failure develops, can improve patient survival. Since it was confirmed that the right-sided heart is particularly involved in the clinical deterioration of patients with COVID-19 and pressure overload-induced RV dysfunction plays a key role for patient outcome, transthoracic echocardiography (TTE) received increasing attention. Limited TTE focused on the right heart appears highly useful in hospitalized COVID-19 patients and particularly beneficial for monitoring of critically ill patients. In addition to detection of right-sided heart dilation and RV dysfunction, it enables assessment of RV-pulmonary arterial coupling and evaluation of RV adaptability to pressure loading which facilitate useful prognostic statements to be made. The increased use of bedside TTE focused on the right heart could facilitate more personalized management and treatment of hospitalized patients and can contribute towards reducing the high mortality associated with SARS-CoV-2 infection.

Forgotten No More-The Role of Right Ventricular Dysfunction in Heart Failure with Reduced Ejection Fraction: An Echocardiographic Perspective

During the last decade, studies have raised awareness of the crucial role that the right ventricle plays in various clinical settings, including diseases primarily linked to the left ventricle. The assessment of right ventricular performance with conventional echocardiography is challenging. Novel echocardiographic techniques improve the functional assessment of the right ventricle and they show good correlation with the gold standard represented by cardiac magnetic resonance. This review summarizes the traditional and innovative echocardiographic techniques used in the functional assessment of the right ventricle, focusing on the role of right ventricular dysfunction in heart failure with reduced ejection fraction and providing a perspective on recent evidence from literature.

Ventricular systolic dysfunction with and without altered myocardial contractility: Clinical value of echocardiography for diagnosis and therapeutic decision-making

The inability of one of the two or both ventricles to contract normally and expel sufficient blood to meet the functional demands of the body results from a complex interplay between intrinsic abnormalities and extracardiac factors that limit ventricular pump function and is a major cause for heart failure (HF). Even if impaired myocardial contractile function was the primary cause for ventricular dysfunction, with the progression of systolic dysfunction, additionally developed diastolic dysfunction can also contribute to the severity of HF. Although at the first sight, the diagnosis of systolic HF appears quite easy because it is usually defined by reduction of the ejection fraction (EF), in reality this issue is far more complex because ventricular pumping performance depends not only on myocardial contractility, but also largely on loading conditions (preload and afterload), being also influenced by valvular function, ventricular interdependence, pericardial constraint, synchrony of ventricular contrac-tion and heart rhythm. Conventional echocardiography (ECHO) combined with new imaging techniques such as tissue Doppler and tissue tracking can detect early subclinical alteration of ventricular systolic function. However, no single ECHO parameter reveals alone the whole picture of systolic dysfunction. Multiparametric ECHO evaluation and the use of integrative approaches using ECHO-parameter combinations which include also the ventricular loading conditions appeared particularly useful especially for differentiation between primary (myocardial damage-induced) and secondary (hemodynamic overload-induced) systolic dysfunction. This review summarizes the available evidence on the usefulness and limitations of comprehensive evaluation of LV and RV systolic function by using all the currently available ECHO techniques.

Utility of tricuspid annular plane systolic excursion normalized by right ventricular size indices in dogs with postcapillary pulmonary hypertension

Background

Tricuspid annular plane systolic excursion (TAPSE) is a common right ventricular (RV) function indicator. However, TAPSE was not decreased in dogs with myxomatous mitral valve disease (MMVD) and postcapillary pulmonary hypertension (PH) because of its load, angle, and body weight dependency, and TAPSE was considered a preload‐dependent index.

Objectives

To evaluate the utility of TAPSE normalized by RV size in dogs with postcapillary PH.

Animals

Twenty healthy dogs and 71 MMVD dogs with or without PH.

Methods

In this prospective observational study, end‐diastolic RV internal dimension (RVIDd), end‐diastolic and end‐systolic RV area, and end‐diastolic RV wall thickness were measured as RV size indices. The TAPSE was measured using B‐mode and M‐mode methods. Normalized TAPSE was calculated by dividing TAPSE by each RV size index. The RV strain was obtained as the detailed RV function using 2‐dimensional speckle tracking echocardiography. All indices were compared among the PH severity groups and in the presence of right‐sided congestive heart failure (R‐CHF).

Results

Although nonnormalized TAPSE was higher with PH severity progression, each normalized TAPSE showed a significant decrease in the severe PH group (P < .05). The TAPSE_B‐mode/RVIDd ratio had high area under the curve to predict R‐CHF and had moderate correlation with RV strain (P < .05). The TAPSE_B‐mode/RVIDd and left atrial‐to‐aortic diameter ratios were independent predictors for R‐CHF.

Conclusions and Clinical Importance

Normalized TAPSE could reflect RV systolic dysfunction in dogs with severe PH, which could not be detected by nonnormalized TAPSE. The TAPSE_B‐mode/RVIDd ratio might predict R‐CHF with high sensitivity and reproducibility.

Right Ventricle Mechanics and Function during Stress in Patients with Asymptomatic Primary Moderate to Severe Mitral Regurgitation and Preserved Left Ventricular Ejection Fraction

Background and objectives. Mitral regurgitation (MR) is usually dynamic and increasing with exertion. Stress may provoke symptoms, cause the progression of pulmonary hypertension (PH) and unmask subclinical changes of the left and right ventricle function. The aim of this study was to evaluate changes of right ventricle (RV) functional parameters during stress and to find out determinants of RV function in patients with MR. Materials and methods. We performed a prospective study that included patients with asymptomatic primary moderate to severe MR and preserved left ventricular (LV) ejection fraction (EF) at rest (≥60%). Conventional 2D echocardiography at rest and during stress (bicycle ergometry) and offline speckle tracking analysis were performed. Results. 80 patients were included as MR (50) and control (30) groups. Conventional functional and myocardial deformation parameters of RV were similar in both groups at all stages of exercise (p > 0.05). The grade of MR (p = 0.004) and higher LV global longitudinal strain (p = 0.037) contributed significantly to the changes of tricuspid annular plane systolic excursion (TAPSE) from rest to peak stress. Changes of MR ERA from the rest to peak stress were related to RV free wall longitudinal strain (FWLS) and four chambers longitudinal stain (4CLS) at rest (p = 0.011; r = −0.459 and p = 0.001; r = −0.572, respectively). Significant correlations between LV EF, stroke volume, cardiac output and RV fractional area change, S′, TAPSE, FWLS, 4CLS were obtained. However, systolic pulmonary artery pressure and RV functional, deformation parameters were not related (p > 0.05). Conclusions. Functional parameters of LV during exercise and severity of MR were significant determinants of RV function while PH has no correlation with it in patients with primary asymptomatic moderate to severe MR.

Prognostic Implications of Right Ventricular Remodeling and Function in Patients With Significant Secondary Tricuspid Regurgitation

BACKGROUND

In patients with significant (moderate and severe) tricuspid regurgitation (TR), the decision to intervene is influenced by right ventricular (RV) size and function. RV remodeling in significant secondary TR has been underexplored. The aim of this study was to characterize RV remodeling in patients with significant secondary TR and to investigate its prognostic implications.

METHODS

RV remodeling was characterized by transthoracic echocardiography in 1292 patients with significant secondary TR (median age 71 [62-78]; 50% male). Four patterns of RV remodeling were defined according to the presence of RV dilation (tricuspid annulus≥40 mm) and RV systolic dysfunction (tricuspid annulus systolic excursion plane<17 mm): pattern 1, normal RV size and systolic function; pattern 2, dilated RV with preserved systolic function; pattern 3, normal RV size with systolic dysfunction; and pattern 4, dilated RV systolic dysfunction. The primary end point was all-cause mortality and the event rates were compared across the 4 patterns of RV remodeling.

RESULTS

A total of 183 (14%) patients showed pattern 1 RV remodeling; 256 (20%) showed pattern 2; 304 (24%) presented with pattern 3; and 549 (43%) had pattern 4 RV remodeling. Patients with pattern 4 RV remodeling were more frequently male; more often had coronary artery disease, worse renal function, and impaired left ventricular ejection fraction; and were more often symptomatic. Only 98 (8%) patients underwent tricuspid valve annuloplasty during follow-up. During a median follow-up of 34 (interquartile range, 0-60) months, 510 (40%) patients died. The 5-year survival rate was significantly worse in patients presenting with patterns 3 and 4 RV remodeling in comparison with pattern 1 (52% and 49% versus 70%; P=0.002 and P<0.001, respectively), and were independently associated with poor outcome on multivariable analysis.

CONCLUSIONS

In patients with significant secondary TR, patients with RV systolic dysfunction have worse clinical outcome regardless of the presence of RV dilation.

Multimodality imaging in ischaemic heart failure

In heart failure, extensive evaluation with modern non-invasive imaging modalities is needed to assess causes, pathophysiology, and haemodynamics, to determine prognosis and consider therapeutic options. This systematic evaluation includes a stepwise assessment of left ventricular size and function, the presence and severity of coronary artery disease, mitral regurgitation, pulmonary hypertension, right ventricular dilation and dysfunction, and tricuspid regurgitation. Based on this imaging-derived information, the need for specific therapies besides optimised medical therapy can be determined. The need for revascularisation, implantation of an implantable cardiac defibrillator, and mitral or tricuspid valve repair or replacement, can be (partially) guided by non-invasive imaging. Importantly, randomised controlled trials on the use of non-inasive imaging to guide therapy are scarce in this field and most non-pharmacological therapies are based on expert-consensus, but whenever trials are available, they will be addressed in this paper.

Right ventricular basal inflow and outflow tract diameters overestimate right ventricular size in subjects with sigmoid-shaped interventricular septum: a study using three-dimensional echocardiography

Sigmoid-shaped ventricular septum (SS), a frequently encountered minor abnormality in echocardiographic examinations of the elderly, may have some influence on RV shape. We aimed to determine the influence of SS on the accuracy of the 6 RV linear diameter measurements in the light of three-dimensional echocardiographic (3DE) RV volume. The aorto-septal angle (ASA) was measured in the parasternal long-axis view using two-dimensional echocardiography (2DE) as an index of SS in 70 patients without major cardiac abnormalities who were subdivided into 35 with SS (ASA ≤ 120°) and 35 without SS (NSS). We measured RV end-diastolic volume (RVEDV) using 3DE; in addition, using 2DE, we measured basal RV diameter, mid-cavity diameter, longitudinal diameter and end-diastolic area in the apical four-chamber view; proximal RV outflow tract (RVOT) diameter in the parasternal long-axis view; and proximal and distal RVOT diameters in the parasternal short-axis view. RVEDV did not differ between the SS and NSS groups. The SS group had greater basal RV diameter and proximal and distal RVOT diameters than the NSS group. RV mid-cavity diameter, longitudinal diameter, and end-diastolic area did not differ between the groups. Among the 2DE parameters of RV size, RV end-diastolic area was most strongly correlated with RVEDV (r = 0.67), followed by RV mid-cavity diameter (r = 0.58). When SS is present, the echocardiographic basal RV diameter and RVOT diameters overestimate RV size, and the measurement of RV end-diastolic area and mid-cavity diameter more correctly reflect 3D RV volume.

Temporary assist device support for the right ventricle: pre-implant and post-implant challenges

Severe right ventricular (RV) failure is more likely reversible than similar magnitudes of left ventricular (LV) failure and, because reversal of both adaptive remodeling and impaired contractility require most often only short periods of support, the use of temporary RV assist devices (t-RVADs) can be a life-saving therapy option for many patients. Although increased experience with t-RVADs and progresses made in the development of safer devices with lower risk for complications has improved both recovery rate of RV function and patient survival, the mortality of t-RVAD recipients can still be high but it depends mainly on the primary cause of RV failure (RVF), the severity of end-organ dysfunction, and the timing of RVAD implantation, and much less on adverse events and complications related to RVAD implantation, support, or removal. Reduced survival of RVAD recipients should therefore not discourage appropriate application of RVADs because their underuse further reduces the chances for RV recovery and patient survival. The article reviews and discusses the challenges related to the pre-implant and post-implant decision-making processes aiming to get best possible therapeutic results. Special attention is focused on pre-implant RV assessment and prediction of RV improvement during mechanical unloading, patient selection for t-RVAD therapy, assessment of unloading-promoted RV recovery, and prediction of its stability after RVAD removal. Particular consideration is also given to prediction of RVF after LVAD implantation which is usually hampered by the complex interactions between the different risk factors related indirectly or directly to the RV potential for reverse remodeling and functional recovery.

Right ventricular mechanics and contractility after aortic valve replacement surgery: a randomised study comparing minimally invasive versus conventional approach

Objective

Minimally invasive aortic valve replacementsurgery (MIAVR) is an alternative surgical technique to conventional aortic valve replacement surgery (AVR) in selected patients. The randomised study Cardiac Function after Minimally Invasive Aortic Valve Implantation (CMILE) showed that right ventricular (RV) longitudinal function was reduced after both MIAVR and AVR, but the reduction was more pronounced following AVR. However, postoperative global RV function was equally impaired in both groups. The purpose of this study was to explore alterations in RV mechanics and contractility following MIAVR as compared with AVR.

Methods

A predefined post hoc analysis of CMILE consisting of 40 patients with severe aortic valve stenosis who were eligible for isolated surgical aortic valve replacement were randomised to MIAVR or AVR. RV function was assessed by echocardiography prior to surgery and 40 days post-surgery.

Results

Comparing preoperative to postoperative values, RV longitudinal strain rate was preserved following MIAVR (−1.5±0.5 vs −1.5±0.4 1/s, p=0.84) but declined following AVR (−1.7±0.3 vs −1.4±0.3 1/s, p<0.01). RV longitudinal strain reduced following AVR (−27.4±2.9% vs −18.8%±4.7%, p<0.001) and MIAVR (−26.5±5.3% vs −20.7%±4.5%, p<0.01). Peak systolic velocity of the lateral tricuspid annulus reduced by 36.6% in the AVR group (9.3±2.1 vs 5.9±1.5 cm/s, p<0.01) and 18.8% in the MIAVR group (10.1±2.9 vs 8.2±1.4 cm/s, p<0.01) when comparing preoperative values with postoperative values.

Conclusions

RV contractility was preserved following MIAVR but was deteriorated following AVR. RV longitudinal function reduced substantially following AVR. A decline in RV longitudinal function was also observed following MIAVR, however, to a much lesser extent.

Tricuspid annular displacement measured by 2-dimensional speckle tracking echocardiography for predicting right ventricular function in pulmonary hypertension: A new approach to evaluating right ventricle dysfunction

This study aimed to determine the ability of tricuspid annular displacement measured by 2-dimensional speckle tracking echocardiography (STE) to predict right ventricular (RV) dysfunction in pulmonary hypertension (PH) patients. Here, we present a new method for assessing RV function that also employs STE and is based on measurement of tricuspid annular displacement.A total of 225 patients were divided into 2 groups according to the pulmonary artery systolic blood pressure (PASP), estimated by echocardiographic measurement of tricuspid regurgitation: group I (PASP ≥50 mm Hg) and group II (36 mm Hg ≤ PASP <50 mm Hg). The tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), RV fractional area change (RVFAC), tissue Doppler-derived tricuspid lateral annular systolic velocity (s'), and the tricuspid annular longitudinal displacement (TMAD) parameters were measured. Thirty patients underwent cardiac magnetic resonance (CMR) examination, and right ventricular ejection fraction (RVEF) was calculated.The conventional parameters as well as the TMAD parameters differed significantly between the 2 groups (all P < .01). Good correlation was observed between the TMAD parameters and CMR-derived RVEF (all P < .01). The TMAD parameters had moderate predictive value for predicting RV dysfunction in PH patients (all P < .01). From receiver operating characteristic curves, we determined the optimal cut-off values for TMAD parameters for detecting RV dysfunction with good sensitivity and specificity.The TMAD parameters can predict the decline of RV function in patients with PH and thus provide new diagnostic indices for clinical management of these patients.

Fibroblasts and the extracellular matrix in right ventricular disease

Right ventricular failure predicts adverse outcome in patients with pulmonary hypertension (PH), and in subjects with left ventricular heart failure and is associated with interstitial fibrosis. This review manuscript discusses the cellular effectors and molecular mechanisms implicated in right ventricular fibrosis. The right ventricular interstitium contains vascular cells, fibroblasts, and immune cells, enmeshed in a collagen-based matrix. Right ventricular pressure overload in PH is associated with the expansion of the fibroblast population, myofibroblast activation, and secretion of extracellular matrix proteins. Mechanosensitive transduction of adrenergic signalling and stimulation of the renin-angiotensin-aldosterone cascade trigger the activation of right ventricular fibroblasts. Inflammatory cytokines and chemokines may contribute to expansion and activation of macrophages that may serve as a source of fibrogenic growth factors, such as transforming growth factor (TGF)-β. Endothelin-1, TGF-βs, and matricellular proteins co-operate to activate cardiac myofibroblasts, and promote synthesis of matrix proteins. In comparison with the left ventricle, the RV tolerates well volume overload and ischemia; whether the right ventricular interstitial cells and matrix are implicated in these favourable responses remains unknown. Expansion of fibroblasts and extracellular matrix protein deposition are prominent features of arrhythmogenic right ventricular cardiomyopathies and may be implicated in the pathogenesis of arrhythmic events. Prevailing conceptual paradigms on right ventricular remodelling are based on extrapolation of findings in models of left ventricular injury. Considering the unique embryologic, morphological, and physiologic properties of the RV and the clinical significance of right ventricular failure, there is a need further to dissect RV-specific mechanisms of fibrosis and interstitial remodelling.

Evaluation of the right ventricle by echocardiography: particularities and major challenges

INTRODUCTION

Compared with the left ventricle (LV), the right ventricle (RV) is less suited for evaluation by echocardiography (ECHO). Nevertheless, RV ECHO-assessment has currently emerged as an important diagnostic tool with meaningful prognostic value and essential contribution to therapeutic decisions. Although significant progress has been made, including generation of higher-quality normative data, validation of several two-dimensional measurements and improvements in three-dimensional ECHO-techniques, many challenges in RV ECHO-assessment still persist. Areas covered: This review discusses the particular challenges and limits in obtaining accurate measurements of RV anatomical and functional parameters and focuses primarily on the difficulties in proper interpretation of the highly load dependent RV ECHO-parameters which complicates the use of this valuable diagnostic and surveillance technique. Expert commentary: There is increasing evidence that RV assessment in relation with its actual loading conditions by ECHO-derived composite variables, which either incorporate a certain functional parameter and load, or incorporate measures which reflect the relationship between RV dilation and RV load, considering also the right atrial pressure (i.e. 'load adaptation index'), is particularly suited for clinical decision-making. Load dependency of RV ECHO-parameters must be taken into consideration especially in patients with advanced RV dysfunction scheduled for LV assist device implantation or lung transplantation.

Echocardiographic evaluation of the right ventricle: Clinical implications

Interest in evaluation of the right ventricle (RV) has increased recently. With the growth of new echocardiographic techniques and technology, there has been a corresponding increase in the ability to evaluate the RV, both qualitatively and quantitatively. Older echocardiographic techniques, such as right ventricular fractional area of change, tricuspid annular plane systolic excursion, and tissue S', and newer echocardiographic techniques including 3-dimensional evaluation and global longitudinal strain, can improve our evaluation of RV function. These techniques provide both diagnostic and prognostic data on a large variety of clinical diseases including pulmonary hypertension and congestive heart failure. With the continuing and exponential advances in technology, echocardiography is well poised to become the primary modality to evaluate the RV.