Predictors and prognosis of right ventricular function in pulmonary hypertension due to heart failure with reduced ejection fraction

Right ventricular dysfunction for prediction of long-term recovery in de novo HFrEF : a PROLONG-II substudy

AIMS

To analyse the predictive value of advanced markers of right ventricular (RV) function and RV-pulmonary arterial (PA) coupling in forecasting long-term left ventricular (LV) improvement in de novo heart failure with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

260 patients (mean age 57 years, 68% men) from the PROLONG-II study were included. PROLONG-II analysed patients with new-onset HFrEF receiving a wearable cardioverter-defibrillator. For this substudy, RV free wall longitudinal strain (RVFWS), tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and right ventricular-pulmonary artery (RV-PA) coupling ratios [RVFWS/systolic pulmonary artery pressure (PASP), TAPSE/PASP and FAC/PASP] at baseline and 3-month follow-up (early follow-up) were examined. LV improvement and non-improvement were defined as an LV ejection fraction (LVEF) of >35% or ≤35% at last available (long-term) follow-up. The median follow-up was 31.5 months (IQR: 18.2-45.4), and 151 (58%) patients experienced LV improvement in the long term. No significant differences of RV function and markers of RV-PA coupling were observed at baseline; however, the subgroup of patients with long-term LVEF improvement showed better RV function at early follow-up (RVFWS -20.9 ± 4.3 vs. -18.5 ± 5.1%, TAPSE 19.7 ± 5.1 vs. 17.4 ± 4.9 mm, FAC 39.7 ± 8.5 vs. 35.2 ± 9.4%, all P < 0.01). In multivariable analysis, RVFWS at early follow-up was shown to be an independent predictor of later LV recovery [odds ratio 1.078 (95% confidence interval 1.010-1.150), P < 0.05]. The non-improvers exhibited worse RV-PA coupling at early follow-up [RVFWS/PASP 0.82 ± 0.35 vs. 0.65 ± 0.35%/mmHg, TAPSE/PASP 0.71 (0.55-1.00) vs. 0.54 (0.35-0.75) mm/mmHg, FAC/PASP 1.54 ± 0.61 vs. 1.24 ± 0.75%/mmHg, all P < 0.01]. RVFWS/PASP identified RV-PA uncoupling was associated with a higher risk of all-cause mortality (hazard ratio 4.64, 95% confidence interval 1.34-16.09, P = 0.033).

CONCLUSIONS

Persistent RV dysfunction, as indicated by both standard and advanced echocardiographic markers during the early follow-up period, implies a reduced potential for long-term LV recovery in patients with newly diagnosed HFrEF.

Therapeutic left-to-right shunting in heart failure

Heart failure with reduced or preserved ejection fraction is associated with elevated left atrial pressure at rest due to fluid overload or during exercise, leading to pulmonary venous congestion. Even with available treatments, heart failure hospitalizations remain high, and improvements in quality-of-life scores and functional capacity are modest. Thus, there is growing interest in non-pharmacological methods to decompress the left atrium and improve heart failure symptoms and outcomes. Left-to-right shunts have emerged as a potential therapeutic option to reduce left atrial hypertension, improve quality of life, and impact long-term outcomes. This nascent field carries both potential therapeutic promise and many unanswered questions. Recent data have questioned whether the effects of this therapy vary based on the left ventricular ejection fraction, pulmonary vascular resistance, and/or right ventricular structure and function. This review discusses the basis for left-to-right shunt therapies, synthesizes past and ongoing clinical trials, and offers future directions.

An Unsupervised Approach to Derive Right Ventricular Pressure-Volume Loop Phenotypes in Pulmonary Hypertension

Although right ventricle (RV) dysfunction drives clinical worsening in pulmonary hypertension (PH), information about RV function has not been well integrated in PH risk assessment. The gold standard for assessing RV function and ventriculo-arterial coupling is the construction of multi-beat pressure-volume (PV) loops. PV loops are technically challenging to acquire and not feasible for routine clinical use. Therefore, we aimed to map standard clinically available measurements to emergent PV loop phenotypes. One hundred and one patients with suspected PH underwent right heart catheterization (RHC) with exercise, multi-beat PV loop measurement, and same-day cardiac magnetic resonance imaging (CMR). We applied unsupervised k-means clustering on 10 PV loop metrics to obtain three patient groups with unique RV functional phenotypes and times to clinical worsening. We integrated RHC and CMR measurements to train a random forest classifier that predicts the PV loop patient group with high discrimination (AUC = 0.93). The most informative variable for PV loop phenotype prediction was exercise mean pulmonary arterial pressure (mPAP). Distinct and clinically meaningful PV loop phenotypes exist that can be predicted using clinically accessible hemodynamic and RV-centric measurements. Exercise mPAP may inform RV pressure-volume relationships.

Prevalence and significance of pulmonary hypertension among hospitalized patients with left heart disease

BACKGROUND

Pulmonary hypertension associated with left heart disease (PH-LHD) prevalence ranges significantly across studies with limited real-world evidence.

OBJECTIVES

To investigate the prevalence and prognostic influence of PH-LHD in a nationwide sample.

METHODS

Using the 2018 US Nationwide Inpatient Sample we calculated the prevalence of PH across heart failure (HF), cardiomyopathies, aortic, and mitral valve disease. We used logistic regression to assess the impact of PH on LHD and to find significant contributors to in-hospital mortality in the PH-LHD population.

RESULTS

Among 6,270,625 hospitalizations with LHD, 801,535 (12.8 %) had a secondary PH diagnosis. PH-LHD prevalence was 17.2 % in HF with preserved ejection fraction (HFpEF), 11.8 % in HF with reduced ejection fraction (HFrEF), 16.8 % in dilated cardiomyopathy, 12.6 % in hypertrophic cardiomyopathy, 18.7 % in mitral regurgitation, 28.5 % in mitral stenosis, 13.5 % in aortic stenosis, and 13.9 % in aortic regurgitation. PH was associated with increased in-hospital mortality in HFpEF (OR 1.23; 95%CI 1.17-1.28), hypertrophic cardiomyopathy (1.42; 1.06-1.89), mitral regurgitation (1.17; 1.07-1.28), and aortic stenosis (1.14; 1.04-1.26), but not in HFrEF (1.04; 0.99-1.10), or dilated cardiomyopathy (1.13; 0.99-1.29). Among PH-LHD, in-hospital mortality was associated with age, atrial fibrillation/flutter, cancer, and acute cardiac (acute right HF, myocardial infarction, ventricular arrhythmia), or extra-cardiac (stroke, sepsis, pneumonia, acute renal failure, venous thromboembolism) diagnoses.

CONCLUSION

In a nationwide inpatient analysis the prevalence of PH-LHD was lower than previously reported indicating reduced recognition of this disease in real world clinical practice. The diagnosis of PH-LHD was associated with worse fatality rates across all forms of LHD, except for HFrEF.

Non-invasive surrogates for right Ventricular-Pulmonary arterial coupling: a systematic review and Meta-Analysis

Right ventricle-pulmonary artery (RV-PA) coupling describes the energetic relationship between RV contractility and its afterload. The gold standard for assessment of this relationship requires invasive pressure-volume (PV) loop measurements. Non-invasive surrogates of RV-PA coupling have been developed, such as the echocardiographic tricuspid annular plane systolic excursion to pulmonary artery systolic pressure ratio (TAPSE/PASP), but their performance has not been systematically assessed. We sought to assess performance of TAPSE/PASP ratio compared to PV loop-defined RV-PA coupling. A systematic search was conducted. Studies were included if PV loop derived RV-PA coupling metrics were compared to echocardiographic or magnetic resonance imaging surrogates. We conducted a meta-analysis of TAPSE/PASP correlation to PV loop-defined RV-PA coupling. 1452 studies were identified in the initial search, of which ten met inclusion criteria. Five studies allowed for pooled analysis of TAPSE/PASP to Ees/Ea correlation (r = 0.52, 95% confidence interval 0.36-0.65). There was moderate heterogeneity across the pooled studies. Despite the common use of Non-invasive surrogates of RV-PA coupling, there is only moderate correlation with gold standard measurements. These metrics do not inform on the individual components of RV-PA coupling, limiting their use in the management of patients with RV dysfunction.

Post-capillary pulmonary hypertension in heart failure: impact of current definition in the PH-HF multicentre study

BACKGROUND AND AIMS

Based on retrospective studies, the 2022 European guidelines changed the definition of post-capillary pulmonary hypertension (pcPH) in heart failure (HF) by lowering the level of mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR). However, the impact of this definition and its prognostic value has never been evaluated prospectively.

METHODS

Stable left HF patients with the need for right heart catheterization were enrolled from 2010 to 2018 and prospectively followed up in this multicentre study. The impact of the successive pcPH definitions on pcPH prevalence and subgroup [i.e. isolated (IpcPH) vs. combined pcPH (CpcPH)] was evaluated. Multivariable Cox regression analysis was used to assess the prognostic value of mPAP and PVR on all-cause death or hospitalization for HF (primary outcome).

RESULTS

Included were 662 HF patients were (median age 63 years, 60% male). Lowering mPAP from 25 to 20 mmHg resulted in +10% increase in pcPH prevalence, whereas lowering PVR from 3 to 2 resulted in +60% increase in CpcPH prevalence (with significant net reclassification improvement for the primary outcome). In multivariable analysis, both mPAP and PVR remained associated with the primary outcome [hazard ratio (HR) 1.02, 95% confidence interval (CI) 1.00-1.03, P = .01; HR 1.07, 95% CI 1.00-1.14, P = .03]. The best PVR threshold associated with the primary outcome was around 2.2 WU. Using the 2022 definition, pcPH patients had worse survival compared with HF patients without pcPH (log-rank, P = .02) as well as CpcPH compared with IpcPH (log-rank, P = .003).

CONCLUSIONS

This study is the first emphasizing the impact of the new pcPH definition on CpcPH prevalence and validating the prognostic value of mPAP > 20 mmHg and PVR > 2 WU among HF patients.

Tricuspid Annular Plane Systolic Excursion-to-Systolic Pulmonary Artery Pressure Ratio as a Prognostic Factor in Heart Transplant Patients

Background and Objectives: Heart transplant is currently the final step in treating patients with heart failure. The success of this procedure is strongly connected to potential complications such as postoperative heart failure, infections, graft rejection, graft vasculopathy, and kidney failure. Thus, identifying potential prognostic factors for patients' outcome is of utmost importance. We investigated the prognostic role of the postoperative ratio between the tricuspid annular plane systolic excursion (TAPSE) and systolic pulmonary artery pressure (sPAP) in patients who underwent heart transplantation in our center. Materials and Methods: The study included 46 adult patients from the Emergency Institute for Cardiovascular Diseases and Transplant of Târgu Mureș, who underwent heart transplant between January 2011 and April 2023. By the use of receiver operating characteristic (ROC) analysis, we determined an optimal cut-off value for TAPSE/sPAP with regard to survival at 6 months. Differences in central tendencies of baseline characteristics in those who had a value lower than the cut-off value of TAPSE/sPAP and those who presented a value above it were investigated using the corresponding parametric or nonparametric tests. Results: A value for TAPSE/sPAP above 0.47 mm/mmHg was associated with 6-month survival (OR: 59.5, CI: 5.7-616.0). No significant differences in central tendencies for baseline characteristics were found between the patients who had a TAPSE/sPAP ratio below the cut-off and those who had a ratio above it. Conclusions: The TAPSE/sPAP ratio might prove to be valuable in the early identification of at-risk heart transplant patients. Further prospective studies with larger cohorts are required for validation.

The Role of Echocardiography in the Diagnosis and Prognosis of Pulmonary Hypertension

The right heart catheterisation constitutes the gold standard for pulmonary hypertension (PH) diagnosis. However, echocardiography remains a reliable, non-invasive, inexpensive, convenient, and easily reproducible modality not only for the preliminary screening of PH but also for PH prognosis. The aim of this review is to describe a cluster of echocardiographic parameters for the detection and prognosis of PH and analyse the challenges of echocardiography implementation in patients with suspected or established PH. The most important echocardiographic index is the calculation of pulmonary arterial systolic pressure (PASP) through the tricuspid regurgitation (TR). It has shown high correlation with invasive measurement of pulmonary pressure, but several drawbacks have questioned its accuracy. Besides this, the right ventricular outflow track acceleration time (RVOT-AT) has been proposed for PH diagnosis. A plethora of echocardiographic indices: right atrial area, pericardial effusion, the tricuspid annular plane systolic excursion (TAPSE), the TAPSE/PASP ratio, tricuspid annular systolic velocity (s'), can reflect the severity and prognosis of PH. Recent advances in echocardiography with 3-dimensional right ventricular (RV) ejection fraction, RV free wall strain and right atrial strain may further assist the prognosis of PH.

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.

Combined use of right ventricular coupling and pulmonary arterial elastance as a comprehensive stratification approach for right ventricular function

Right ventricular (RV)-pulmonary arterial uncoupling is the consequence of increased afterload and/or decreased RV contractility. However, the combination of arterial elastance (Ea) and end-systolic elastance (Ees)/Ea ratio to assess RV function is unclear. We hypothesized that the combination of both could comprehensively assess RV function and refine risk stratification. The median Ees/Ea ratio (0.80) and Ea (0.59 mmHg/mL) were used to classify 124 patients with advanced heart failure into four groups. RV systolic pressure differential was defined as end-systolic pressure (ESP) minus beginning-systolic pressure (BSP). Patients among different subsets showed dissimilar New York Heart Association functional class (V = 0.303, p = 0.010), distinct tricuspid annular plane systolic excursion/ pulmonary artery systolic pressure (mm/mmHg; 0.65 vs. 0.44 vs. 0.32 vs. 0.26, p < 0.001), and diverse prevalence of pulmonary hypertension (33.3% vs. 35% vs. 90% vs. 97.6%, p < 0.001). By multivariate analysis, Ees/Ea ratio (hazard ratio [HR] 0.225, p = 0.004) and Ea (HR 2.194, p = 0.003) were independently associated with event-free survival. Patients with Ees/Ea ratio greater than or equal to 0.80 and Ea less than 0.59 mmHg/mL had better outcomes (p < 0.05). In patients with Ees/Ea ratio greater than or equal to 0.80, those with Ea greater than or equal to 0.59 mmHg/mL had a higher adverse outcome risk (p < 0.05). Ees/Ea ratio less than or equal to 0.80 was associated with adverse outcomes, even when Ea was less than 0.59 mmHg/mL (p < 0.05). Approximately 86% of patients with ESP-BSP greater than 5 mmHg had an Ees/Ea ratio less than or equal to 0.80 and/or an Ea greater than or equal to 0.59 mmHg/mL (V = 0.336, p = 0.001). Combined use of Ees/Ea ratio and Ea could be a comprehensive approach to assessing RV function and predicting outcomes. An exploratory analysis demonstrated that Ees/Ea ratio and Ea might be roughly estimated based on RV systolic pressure differential.

Right ventricular global dysfunction score: a new concept of right ventricular function assessment in patients with heart failure with reduced ejection fraction (HFrEF)

Background

Right ventricular (RV) function is currently being evaluated solely according to the properties of RV myocardium. We have tested a concept that in patients with heart failure with reduced ejection fraction (HFrEF), RV assessment should integrate the information about both RV function as well as size.

Methods

A total of 836 stable patients with HFrEF (LVEF 23.6 ± 5.8%, 82.8% males, 68% NYHA III/IV) underwent echocardiographic evaluation and were prospectively followed for a median of 3.07 (IQRs 1.11; 4.89) years for the occurrence of death, urgent heart transplantation or implantation of mechanical circulatory support.

Results

RV size (measured as RV-basal diameter, RVD1) was significantly associated with an adverse outcome independent of RV dysfunction grade (p = 0.0002). The prognostic power of RVD1 was further improved by indexing to body surface area (RVD1i, p < 0.05 compared to non-indexed value). A novel parameter named RV global dysfunction score (RVGDs) was calculated as a product of RVD1i and the degree of RV dysfunction (1-4 for preserved RV function, mild, moderate and severe dysfunction, respectively). RVGDs showed a superior prognostic role compared to RV dysfunction grade alone (ΔAUC >0.03, p < 0.0001). In every subgroup of RVGDs (<20, 20-40, 40-60, >60), patients with milder degree of RV dysfunction but more dilated RV had similar outcome as those with more severe degree of RV dysfunction but smaller RV size (all p > 0.50), independent of tricuspid regurgitation severity and degree of pulmonary hypertension.

Conclusion

RV dilatation is a manifestation of RV dysfunction. The evaluation of RV performance should integrate the information about both RV size and function.

Pressure Overload and Right Ventricular Failure: From Pathophysiology to Treatment

Right ventricular failure (RVF) is often caused by increased afterload and disrupted coupling between the right ventricle (RV) and the pulmonary arteries (PAs). After a phase of adaptive hypertrophy, pressure-overloaded RVs evolve towards maladaptive hypertrophy and finally ventricular dilatation, with reduced stroke volume and systemic congestion. In this article, we review the concept of RV-PA coupling, which depicts the interaction between RV contractility and afterload, as well as the invasive and non-invasive techniques for its assessment. The current principles of RVF management based on pathophysiology and underlying etiology are subsequently discussed. Treatment strategies remain a challenge and range from fluid management and afterload reduction in moderate RVF to vasopressor therapy, inotropic support and, occasionally, mechanical circulatory support in severe RVF.

A new assessment method for right ventricular diastolic function using right heart catheterization by pressure-volume loop

Diastolic stiffness coefficient (β) and end-diastolic elastance (Eed) are ventricular-specific diastolic parameters. However, the diastolic function of right ventricle had not been investigated sufficiently due to the lack of established evaluation method. We evaluated the validity of these parameters calculated using only data of right heart catheterization (RHC) and assessed it in patients with restrictive cardiomyopathy (RCM) and cardiac amyloidosis. We retrospectively analyzed 46 patients with heart failure who underwent RHC within 10 days of cardiac magnetic resonance (CMR). Right ventricular end-diastolic volume and end-systolic volume were calculated using only RHC data, which were found to be finely correlated with those obtained from CMR. β and Eed calculated by this method were also significantly correlated with those derived from conventional method using CMR. By this method, β and Eed were significantly higher in RCM with amyloidosis group than dilated cardiomyopathy group. In addition, the β and Eed calculated by our method were finely correlated with E/A ratio on echocardiography. We established an easy method to estimate β and Eed of right ventricle from only RHC. The method finely demonstrated right ventricular diastolic dysfunction in patients with RCM and amyloidosis.

Management of Acute Right Ventricular Failure

PURPOSE OF REVIEW

Acute right ventricular failure (RVF) is a frequent condition associated with high morbidity and mortality. This review aims to provide a current overview of the pathophysiology, presentation, and comprehensive management of acute RVF.

RECENT FINDINGS

Acute RVF is a common disease with a pathophysiology that is not completely understood. There is renewed interest in the right ventricle (RV). Some advances have been principally made in chronic right ventricular failure (e.g., pulmonary hypertension). Due to a lack of precise definition and diagnostic tools, acute RVF is poorly studied. Few advances have been made in this field. Acute RVF is a complex, frequent, and life-threatening condition with several etiologies. Transthoracic echocardiography (TTE) is the key diagnostic tool in search of the etiology. Management includes transfer to an expert center and admission to the intensive care unit (ICU) in most severe cases, etiological treatment, and general measures for RVF.

The emerging role of sacubitril/valsartan in pulmonary hypertension with heart failure

Pulmonary hypertension due to left heart disease (PH-LHD) represents approximately 65%-80% of all patients with PH. The progression, prognosis, and mortality of individuals with left heart failure (LHF) are significantly influenced by PH and right ventricular (RV) dysfunction. Consequently, cardiologists should devote ample attention to the interplay between HF and PH. Patients with PH and HF may not receive optimal benefits from the therapeutic effects of prostaglandins, endothelin receptor antagonists, or phosphodiesterase inhibitors, which are specific drugs for pulmonary arterial hypertension (PAH). Sacubitril/valsartan, the angiotensin receptor II blocker-neprilysin inhibitor (ARNI), was recommended as the first-line therapy for patients with heart failure with reduced ejection fraction (HFrEF) by the 2021 European Society of Cardiology Guidelines. Although ARNI is effective in treating left ventricular (LV) enlargement and lower ejection fraction, its efficacy in treating individuals with PH and HF remains underexplored. Considering its vasodilatory effect at the pre-capillary level and a natriuretic drainage role at the post-capillary level, ARNI is believed to have a broad range of potential applications in treating PH-LHD. This review discusses the fundamental pathophysiological connections between PH and HF, emphasizing the latest research and potential benefits of ARNI in PH with various types of LHF and RV dysfunction.

Role of the Femoral Vein Doppler in Acute Heart Failure Patients: results from a prospective multicentric study

BACKGROUND AND OBJECTIVE

The aim of our study is to define the role of Pulsed-Doppler (PW-Doppler) Ultrasound of the Common Femoral Vein (CFV) in the assessment of dilatation Inferior Vena Cava (IVC), probability of Pulmonary Hypertension (PH), Tricuspid Regurgitation (TR), and Tricuspid annular plane systolic excursion (TAPSE).

METHODS

This is a prospective two-hospital study in 74 patients admitted with acute heart failure (AHF). We performed PW-Doppler ultrasound of the common femoral vein, Point of Care (POC) cardiac ultrasonography and assessment of the IVC at the time of admission, as well as PW-Doppler and ultrasound of the IVC at hospital discharge.

RESULTS

The detection of a pulsatile flow (138 scans) had an excellent ROC curve for the detection of IVC greater than 2 cm (AUC 0.931, Sn 95%, Sp 90%, PPV 93%, NPV 94%) with an Odds Ratio (OR) of 211.2 (95% confidence interval 48.13-926.72). The pulsatility of the flow also had the highest performance in the detection of PH (AUC 0.8, Sn 95%, Sp 64%, PPV 84%, NPV 84%) and in the detection of moderate-severe TR (AUC 0.79, Sn 95%, Sp 67%, PPV 88%, NPV 78%). If the flow is continuous, we can reasonably rule out diminished TAPSE (NPV 89%).

CONCLUSSION

Detection of PW-Doppler flow of the CFV may be an alternative window for the detection of an IVC dilation of 2 cm, significant TR, and the likelihood of high PH in acute heart failure. It also allows us to reasonably rule out dysfunction of the right ventricle in cases of normality in these patients.

Adaptive versus maladaptive right ventricular remodelling

Right ventricular (RV) function and its adaptation to increased afterload [RV-pulmonary arterial (PA) coupling] are crucial in various types of pulmonary hypertension, determining symptomatology and outcome. In the course of disease progression and increasing afterload, the right ventricle undergoes adaptive remodelling to maintain right-sided cardiac output by increasing contractility. Exhaustion of compensatory RV remodelling (RV-PA uncoupling) finally leads to maladaptation and increase of cardiac volumes, resulting in heart failure. The gold-standard measurement of RV-PA coupling is the ratio of contractility [end-systolic elastance (Ees)] to afterload [arterial elastance (Ea)] derived from RV pressure-volume loops obtained by conductance catheterization. The optimal Ees/Ea ratio is between 1.5 and 2.0. RV-PA coupling in pulmonary hypertension has considerable reserve; the Ees/Ea threshold at which uncoupling occurs is estimated to be ~0.7. As RV conductance catheterization is invasive, complex, and not widely available, multiple non-invasive echocardiographic surrogates for Ees/Ea have been investigated. One of the first described and best validated surrogates is the ratio of tricuspid annular plane systolic excursion to estimated pulmonary arterial systolic pressure (TAPSE/PASP), which has shown prognostic relevance in left-sided heart failure and precapillary pulmonary hypertension. Other RV-PA coupling surrogates have been formed by replacing TAPSE with different echocardiographic measures of RV contractility, such as peak systolic tissue velocity of the lateral tricuspid annulus (S'), RV fractional area change, speckle tracking-based RV free wall longitudinal strain and global longitudinal strain, and three-dimensional RV ejection fraction. PASP-independent surrogates have also been studied, including the ratios S'/RV end-systolic area index, RV area change/RV end-systolic area, and stroke volume/end-systolic volume. Limitations of these non-invasive surrogates include the influence of severe tricuspid regurgitation (which can cause distortion of longitudinal measurements and underestimation of PASP) and the angle dependence of TAPSE and PASP. Detection of early RV remodelling may require isolated analysis of single components of RV shortening along the radial and anteroposterior axes as well as the longitudinal axis. Multiple non-invasive methods may need to be applied depending on the level of RV dysfunction. This review explains the mechanisms of RV (mal)adaptation to its load, describes the invasive assessment of RV-PA coupling, and provides an overview of studies of non-invasive surrogate parameters, highlighting recently published works in this field. Further large-scale prospective studies including gold-standard validation are needed, as most studies to date had a retrospective, single-centre design with a small number of participants, and validation against gold-standard Ees/Ea was rarely performed.

Clinical Usefulness of Right Ventricle-Pulmonary Artery Coupling in Cardiovascular Disease

Right ventricular-pulmonary artery coupling (RV-PA coupling) refers to the relationship between RV contractility and RV afterload. Normal RV-PA coupling is maintained only when RV function and pulmonary vascular resistance are appropriately matched. RV-PA uncoupling occurs when RV contractility cannot increase to match RV afterload, resulting in RV dysfunction and right heart failure. RV-PA coupling plays an important role in the pathophysiology and progression of cardiovascular diseases. Therefore, early and accurate evaluation of RV-PA coupling is of great significance for a patient's condition assessment, clinical decision making, risk stratification, and prognosis judgment. RV-PA coupling can be assessed by using invasive or noninvasive approaches. The aim of this review was to summarize the pathological mechanism and evaluation methods of RV-PA coupling, the advantages and disadvantages of each method, and the application value of RV-PA coupling in various cardiovascular diseases.

Natural Products for the Treatment of Pulmonary Hypertension: Mechanism, Progress, and Future Opportunities

Pulmonary hypertension (PH) is a lethal disease due to the remodeling of pulmonary vessels. Its pathophysiological characteristics include increased pulmonary arterial pressure and pulmonary vascular resistance, leading to right heart failure and death. The pathological mechanism of PH is complex and includes inflammation, oxidative stress, vasoconstriction/diastolic imbalance, genetic factors, and ion channel abnormalities. Currently, many clinical drugs for the treatment of PH mainly play their role by relaxing pulmonary arteries, and the treatment effect is limited. Recent studies have shown that various natural products have unique therapeutic advantages for PH with complex pathological mechanisms owing to their multitarget characteristics and low toxicity. This review summarizes the main natural products and their pharmacological mechanisms in PH treatment to provide a useful reference for future research and development of new anti-PH drugs and their mechanisms.

Computational modelling of multi-temporal ventricular-vascular interactions during the progression of pulmonary arterial hypertension

A computational framework is developed to consider the concurrent growth and remodelling (G&R) processes occurring in the large pulmonary artery (PA) and right ventricle (RV), as well as ventricular-vascular interactions during the progression of pulmonary arterial hypertension (PAH). This computational framework couples the RV and the proximal PA in a closed-loop circulatory system that operates in a short timescale of a cardiac cycle, and evolves over a long timescale due to G&R processes in the PA and RV. The framework predicts changes in haemodynamics (e.g. 68.2% increase in mean PA pressure), RV geometry (e.g. 38% increase in RV end-diastolic volume) and PA tissue microstructure (e.g. 90% increase in collagen mass) that are consistent with clinical and experimental measurements of PAH. The framework also predicts that a reduction in RV contractility is associated with long-term RV chamber dilation, a common biomarker observed in the late-stage PAH. Sensitivity analyses on the G&R rate constants show that large PA stiffening (both short and long term) is affected by RV remodelling more than the reverse. This framework can serve as a foundation for the future development of a more predictive and comprehensive cardiovascular G&R model with realistic heart and vascular geometries.

Right ventricular failure in left heart disease: from pathophysiology to clinical manifestations and prognosis

Right heart failure (RHF) is a clinical syndrome in which symptoms and signs are caused by dysfunction and/or overload of the right heart structures, predominantly the right ventricle (RV), resulting in systemic venous hypertension, peripheral oedema and finally, the impaired ability of the right heart to provide tissue perfusion. Pathogenesis of RHF includes the incompetence of the right heart to maintain systemic venous pressure sufficiently low to guarantee an optimal venous return and to preserve renal function. Virtually, all myocardial diseases involving the left heart may be responsible for RHF. This may result from coronary artery disease, hypertension, valvular heart disease, cardiomyopathies and myocarditis. The most prominent clinical signs of RHF comprise swelling of the neck veins with an elevation of jugular venous pressure and ankle oedema. As the situation worsens, fluid accumulation becomes generalised with extensive oedema of the legs, congestive hepatomegaly and eventually ascites. Diagnosis of RHF requires the presence of signs of elevated right atrial and venous pressures, including dilation of neck veins, with at least one of the following criteria: (1) compromised RV function; (2) pulmonary hypertension; (3) peripheral oedema and congestive hepatomegaly. Early recognition of RHF and identifying the underlying aetiology as well as triggering factors are crucial to treating patients and possibly reversing the clinical manifestations effectively and improving prognosis.

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.

Utility of the tricuspid annular tissue doppler systolic velocity and pulmonary artery systolic pressure relationship in right ventricular systolic function assessment: A pilot study

BACKGROUND

Tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio has been validated as a valuable noninvasive measure of right ventricular (RV) elastance and systolic function. However, the more reliable TA systolic (s') velocity measure of RV systolic function compared to TAPSE has not been previously studied.

METHODS

We conducted a pilot study using several variables of RV function in 50 patients with the main aim to determine which numerical expression between TA TDI s'/PASP and TAPSE/PASP ratio was most useful.

RESULTS

In a stepwise multiple regression analysis, TA TDI s'/PASP ratio (p < .0002); LVOT VTI/RVOT VTI ratio (p < .0002); RVOT VTI (p < .0047); TAPSE/PASP ratio (p < .0259) and TA TDI e' (p < .0292) were best in discriminating normal versus abnormal RV systolic function. Using receiver operator curve analysis, cut-off values for both TA TDI s'/PASP (>3.9 mm/c/mmHg) had 82.1% sensitivity and 77.3% specificity while the TAPSE/PASP (>.61 mm/mmHg) had 89.3% sensitivity and 68.2% specificity in identifying normal RV function in our studied population.

CONCLUSION

Our results indicate that TA TDI s'/PASP is a better mathematical expression when examining the relationship between RV contractility and RV resistance relationship. Furthermore, we also found that inclusion of RVOT VTI, RV diastolic properties, and left ventricular systolic function are important determinants of RV systolic function assessments and should be routinely included. Additional prospective studies are now needed to confirm these results using hemodynamic data.

Decongestion improving right heart function ameliorates prognosis after an acute heart failure episode

BACKGROUND

The prognostic role of decongestion-related change of cardiac morphology and in particular right heart function has not been investigated comprehensively in AHF patients.

METHODS AND RESULTS

This prospective observational single-centre study included consecutive patients hospitalized for treatment of AHF with reduced, mildly-reduced or preserved left ventricular ejection fraction (LVEF). Comprehensive transthoracic echocardiography at admission and discharge assessed decongestion-related change of cardiac function and morphology. The combined endpoint of 1 year all-cause mortality and cardiovascular rehospitalization explored the prognostic importance of decongestion-related change. The 176 study participants were 83 years old [74-87] and 54% were men. Fifty one (29%) had rLVEF, 65 (37%) mrLVEF, and 60 (34%) pLVEF. The proportion of de novo or worsening chronic HF was not different between LVEF groups. HF aetiology and cardiovascular risk factors were equally distributed across all groups except for a higher BMI in the pLVEF group. Decongestion equally reduced body weight, heart rate, systolic and diastolic blood pressure, tricuspid regurgitation gradient, and inferior vena cava diameter across all groups (P < 0.004 for all). Decongestion-related increase in TAPSE independent of the LVEF was associated with improvement of right-ventricular-pulmonary artery coupling and a lower incidence of the combined outcome in the Cox proportional hazard risk analysis (unadjusted HR 0.50 95% CI 0.33-0.78, P = 0.002; adjusted HR 0.46 95% CI: 0.33-0.78, P = 0.001).

CONCLUSIONS

Decongestion-related increase in TAPSE and recovery of RV/pulmonary artery coupling was observed across all LVEF groups and associated with a risk reduction for the combined endpoint highlighting the important prognostic role of right heart recovery after an AHF episode.

Right ventricle remodeling in chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed, but potentially curable pulmonary vascular disease. The increased pulmonary vascular resistance in CTEPH is caused by unresolved proximal thrombus and secondary microvasculopathy in the pulmonary vasculature, leading to adaptive and maladaptive remodeling of the right ventricle (RV), eventual right heart failure, and death. Knowledge on the RV remodeling process in CTEPH is limited. The progression to RV failure in CTEPH is a markedly slower process. A detailed understanding of the pathophysiology and underlying mechanisms of RV remodeling may facilitate early diagnosis and the development of targeted therapy. While ultrasound, magnetic resonance imaging, right heart catheterization, and serum biomarkers have been used to assess cardiac function, the current treatment strategies reduce the afterload of the right heart, but are less effective in improving the maladaptive remodeling of the right heart. This review systematically summarizes the current knowledge on adaptive and maladaptive remodeling of the right heart in CTEPH from molecular mechanisms to clinical practice.

Prognostic Role of Subclinical Congestion in Heart Failure Outpatients: Focus on Right Ventricular Dysfunction

BACKGROUND

subclinical pulmonary and peripheral congestion is an emerging concept in heart failure, correlated with a worse prognosis. Very few studies have evaluated its prognostic impact in an outpatient setting and its relationship with right-ventricular dysfunction. The study aims to investigate subclinical congestion in chronic heart failure outpatients, exploring the close relationship between the right heart-pulmonary unit and peripheral congestion.

MATERIALS AND METHODS

in this observational study, 104 chronic HF outpatients were enrolled. The degree of congestion and signs of elevated filling pressures of the right ventricle were evaluated by physical examination and a transthoracic ultrasound to define multiparametric right ventricular dysfunction, estimate the right atrial pressure and the pulmonary artery systolic pressure. Outcome data were obtained by scheduled visits and phone calls.

RESULTS

ultrasound signs of congestion were found in 26% of patients and, among this cohort, half of them presented as subclinical, affecting their prognosis, revealing a linear correlation between right ventricular/arterial coupling, the right-chambers size and ultrasound congestion. Right ventricular dysfunction, TAPSE/PAPS ratio, clinical and ultrasound signs of congestion have been confirmed to be useful predictors of outcome.

CONCLUSIONS

subclinical congestion is widespread in the heart failure outpatient population, significantly affecting prognosis, especially when right ventricular dysfunction also occurs, suggesting a strict correlation between the heart-pulmonary unit and volume overload.

Predictors and prognosis of right ventricular function in pulmonary hypertension due to heart failure with reduced ejection fraction

Aims

Failure of right ventricular (RV) function worsens outcome in pulmonary hypertension (PH). The adaptation of RV contractility to afterload, the RV‐pulmonary artery (PA) coupling, is defined by the ratio of RV end‐systolic to PA elastances (Ees/Ea). Using pressure–volume loop (PV‐L) technique we aimed to identify an Ees/Ea cut‐off predictive for overall survival and to assess hemodynamic and morphologic conditions for adapted RV function in secondary PH due to heart failure with reduced ejection fraction (HFREF).

Methods and results

This post hoc analysis is based on 112 patients of the prospective Magdeburger Resynchronization Responder Trial. All patients underwent right and left heart echocardiography and a baseline PV‐L and RV catheter measurement. A subgroup of patients (n = 50) without a pre‐implanted cardiac device underwent magnetic resonance imaging at baseline. The analysis revealed that 0.68 is an optimal Ees/Ea cut‐off (area under the curve: 0.697, P < 0.001) predictive for overall survival (median follow up = 4.7 years, Ees/Ea ≥ 0.68 vs. <0.68, log‐rank 8.9, P = 0.003). In patients with PH (n = 76, 68%) multivariate Cox regression demonstrated the independent prognostic value of RV‐Ees/Ea in PH patients (hazard ratio 0.2, P < 0.038). Patients without PH (n = 36, 32%) and those with PH but RV‐Ees/Ea ≥ 0.68 showed comparable RV‐Ees/Ea ratios (0.88 vs. 0.9, P = 0.39), RV size/function, and survival. In contrast, secondary PH with RV‐PA coupling ratio Ees/Ea < 0.68 corresponded extremely close to cut‐off values that define RV dilatation/remodelling (RV end‐diastolic volume >160 mL, RV‐mass/volume‐ratio ≤0.37 g/mL) and dysfunction (right ventricular ejection fraction <38%, tricuspid annular plane systolic excursion <16 mm, fractional area change <42%, and stroke‐volume/end‐systolic volume ratio <0.59) and is associated with a dramatically increased short and medium‐term all‐cause mortality. Independent predictors of prognostically unfavourable RV‐PA coupling (Ees/Ea < 0.68) in secondary PH were a pre‐existent dilated RV [end‐diastolic volume >171 mL, odds ratio (OR) 0.96, P = 0.021], high pulsatile load (PA compliance <2.3 mL/mmHg, OR 8.6, P = 0.003), and advanced systolic left heart failure (left ventricular ejection fraction <30%, OR 1.23, P = 0.028).

Conclusions

The RV‐PA coupling ratio Ees/Ea predicts overall survival in PH due to HFREF and is mainly affected by pulsatile load, RV remodelling, and left ventricular dysfunction. Prognostically favourable coupling (RV‐Ees/Ea ≥ 0.68) in PH was associated with preserved RV size/function and mid‐term survival, comparable with HFREF without PH.