The right ventricle in pulmonary hypertension

Pulmonary Hypertension Phenotypes in Systemic Sclerosis: The Right Diagnosis for the Right Treatment

Systemic sclerosis is an auto-immune disease characterized by skin involvement that often affects multiple organ systems. Pulmonary hypertension is a common finding that can significantly impact prognosis. Molecular pathophysiological mechanisms underlying pulmonary hypertension in systemic sclerosis can be extremely heterogeneous, leading to distinct clinical phenotypes. In addition, different causes of pulmonary hypertension may overlap within the same patient. Since pulmonary hypertension treatment is very different for each phenotype, it is fundamental to perform an adequate diagnostic work-up to properly and promptly identify the prevalent mechanism underlying pulmonary hypertension in order to start the right therapies. When pulmonary hypertension is caused by a primary vasculopathy of the small pulmonary arteries, treatment with pulmonary vasodilators, often in an initial double-combination regimen, is indicated, aimed at reducing the mortality risk profile. In this review, we describe the different clinical phenotypes of pulmonary hypertension in the scleroderma population and discuss the utility of clinical tools to identify the presence of pulmonary vascular disease. Furthermore, we focus on systemic sclerosis-associated pulmonary arterial hypertension, highlighting the advances in the knowledge of right ventricular dysfunction in this setting and the latest updates in terms of treatment with pulmonary vasodilator drugs.

Bionic women and men - Part 3: Right ventricular dysfunction in patients implanted with left ventricular assist devices

NEW FINDINGS

What is the topic of this review? Right heart dysfunction remains a major adverse event in patients with end stage heart failure undergoing left ventricular assist device placement. This article reviews the pathophysiology and clinical considerations of right heart failure in this patient population. What advances does it highlight? This review highlights the anatomic and physiological peculiarities of the interplay between left and right heart function in patients undergoing LVAD therapy. These would allow us to further advance our understanding of right ventricular function.

ABSTRACT

The adaptation of the right ventricular (RV) output to a left ventricular assist device (LVAD) often determines the fate of patients with pulmonary hypertension secondary to left heart failure. Pre-existing right heart dysfunction in patients with advanced left heart failure is the consequence of increased (arterial) afterload and not simply the consequence of myocardial disease. If unaccounted for, it has the potential of accelerating into clinical right heart failure after LVAD, leading to significant morbidity and mortality. After LVAD implantation, the RV has to face increased flow generated by the LVAD, cardiac arrhythmias and exaggerated functional interactions between both ventricles. Understanding the key physiological mechanisms of RV dysfunction in patients with end-stage heart failure will allow us to predict and therefore prevent RV failure after LVAD implantation.

Noninvasive Leg-Positive Pressure Stress Echocardiography Reveals Preload Reserve in Adult Patients after Complete Repair of Tetralogy of Fallot

BACKGROUND

Long-term sequelae such as right ventricular dysfunction and reduced hemodynamic reserve are the main determinants of cardiovascular outcomes after repair of tetralogy of Fallot (TOF). Echocardiographic parameters at rest offer only partial information on impaired hemodynamics in these patients, and data during stress testing are lacking. The leg-positive pressure (LPP) maneuver has recently been reported to be able to apply acute preload stress. The aim of this study was to test the hypothesis that preload reserve is impaired and ventricular interaction is exacerbated in patients with TOF.

METHODS

In this prospective cross-sectional study, we recruited 44 consecutive patients with TOF and 30 normal control subjects. Echocardiography was performed both at rest and during LPP stress, and preload reserve was defined as the change between baseline stroke volume (SV) and that obtained during LPP stress. The eccentricity index was calculated as the ratio of the left ventricular anteroposterior to septal-lateral dimensions to quantify ventricular interaction.

RESULTS

LPP stress significantly increased SV from 73 ± 14 to 83 ± 16 mL (P < .01) in control subjects, while the increase in SV was significantly blunted (from 75 ± 19 to 79 ± 18 mL; P < .01 for interaction) in patients with TOF. The eccentricity index significantly changed during LPP stress in patients with TOF only from 1.07 ± 0.13 to 1.13 ± 0.14 (P < .01 for interaction). Patients with TOF were subdivided into two subgroups on the basis of the median value of increased response in SV (22 with sufficient and 22 with insufficient preload reserve). Multivariate analysis identified significant pulmonary regurgitation as the only independent determinant factor for insufficient preload reserve (odds ratio, 4.57; 95% CI, 1.048-19.90; P = .04).

CONCLUSIONS

In patients after repair of TOF, ventricular interaction was exacerbated and preload reserve was impaired, especially in patients with significant pulmonary regurgitation. LPP stress testing may direct tailored treatment approaches, risk stratification, and clinical decision-making, such as more aggressive pharmacologic therapy, meticulous outpatient follow-up, or earlier reintervention.

Effects of balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension on remodeling in right-sided heart

Remodeling in the right-sided heart plays an important role in the management of pulmonary hypertension (PH) patients. However, the effect of balloon pulmonary angioplasty (BPA) on right ventricular (RV) and right atrial (RA) morphology of patients with chronic thromboembolic pulmonary hypertension (CTEPH) remains uncertain. This study involved 45 CTEPH patients who underwent BPA with mean pulmonary artery pressure (mPAP) of 37.0 mmHg (all ≥ 25 mmHg). All patients underwent echocardiography and right-heart catheterization at baseline and 3 months after BPA. RV and RA remodeling was assessed as RV and the RA area, and RV systolic function was calculated by averaging peak speckle-tracking longitudinal strain of the RV free-wall (RV free-wall strain). Significant reverse remodeling in the right-sided heart was observed after BPA, resulting in improvement of mPAP and pulmonary vascular resistance (RV area: from 15.0 ± 5.3 to 9.6 ± 3.0 cm², p < 0.0001; RA area: from 17.3 ± 6.6 to 13.4 ± 3.8 cm², p = 0.0002; RV free-wall strain: from 15.9 ± 5.6 to 21.2 ± 4.9%, p < 0.0001). Furthermore, multiple regression analysis showed that the baseline RV area was an independent predictor of post-BPA normalization of RV systolic function defined as RV free-wall strain ≥ 20% (odds ratio = 1.16, p = 0.0305). Interestingly, significant RV reverse remodeling was also observed after additional BPA even in 18 CTEPH patients with residual pulmonary arterial stenosis, whose mPAP was normalized after BPA (RV area: from 11.5 ± 3.8 to 9.2 ± 3.8 cm², p = 0.0045; RV free-wall strain: from 17.2 ± 4.8 to 22.8 ± 7.4%, p = 0.0216). Significant reverse remodeling in the right-sided heart, as well as hemodynamic improvement, was observed in CTEPH patients after BPA.

Congenital diaphragmatic hernia-associated cardiac dysfunction

There is increasing evidence that cardiac dysfunction is a key contributor to CDH pathophysiology. Dysfunction in both right and left ventricles is common in the early neonatal period, contributes to clinical disease severity, and is associated with adverse outcomes including death and ECMO use. Early and routine assessment of ventricular function and pulmonary artery pressure may guide individualized clinical decision-making, including use of pulmonary vasodilators, cardiotropes, ECMO, and timing of surgical repair. Minimizing cardiac dysfunction, whether by prenatal, postnatal or perinatal treatment strategies, may lead to improved outcome in CDH.

Targeting epigenetic mechanisms as an emerging therapeutic strategy in pulmonary hypertension disease

Pulmonary arterial hypertension (PAH) is a multifactorial cardiopulmonary disease characterized by an elevation of pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR), which can lead to right ventricular (RV) failure, multi-organ dysfunction, and ultimately to premature death. Despite the advances in molecular biology, the mechanisms underlying pulmonary hypertension (PH) remain unclear. Nowadays, there is no curative treatment for treating PH. Therefore, it is crucial to identify novel, specific therapeutic targets and to offer more effective treatments against the progression of PH. Increasing amounts of evidence suggest that epigenetic modification may play a critical role in the pathogenesis of PAH. In the presented paper, we provide an overview of the epigenetic mechanisms specifically, DNA methylation, histone acetylation, histone methylation, and ncRNAs. As the recent identification of new pharmacological drugs targeting these epigenetic mechanisms has opened new therapeutic avenues, we also discuss the importance of epigenetic-based therapies in the context of PH.

The practical management of fluid retention in adults with right heart failure due to pulmonary arterial hypertension

Our aim with this review is to provide practical advice and management support for nurses and other healthcare practitioners in managing fluid retention in adults with right heart failure (RHF) due to pulmonary arterial hypertension (PAH). Vigilant management of RHF is important for maintaining patient quality of life, as fluid overload can lead to abdominal bloating (ascites) and peripheral oedema, which also has a major impact on patients' morbidity and mortality. Patients with RHF should be assessed regularly for signs of fluid retention. If fluid overload develops, it is important to determine whether it is caused by the progression of PAH, a side effect of PAH-specific treatment, or another drug or comorbid condition, as this affects both the prognosis and the management strategy. Right heart failure can be treated with both pharmacological and non-pharmacological interventions to reduce fluid retention; including altering fluid and salt intake, weight monitoring, and use of diuretics. All patients on diuretics should be regularly monitored for renal dysfunction and electrolyte imbalance and given advice on how to manage the side effects associated with diuretic use. Fluid retention is often assessed and treated in clinical practice by specialist nurses, who act as a key patient contact providing advice and information on symptom management. This review provides an overview of the challenges related to fluid retention, including strategies to help patients manage symptoms and side effects of treatment.

Primary cardiac hospitalizations in pulmonary arterial hypertension: Trends and outcomes from 2001 to 2014

BACKGROUND

Hospitalizations in pulmonary arterial hypertension (PAH) are common and are often for cardiac conditions. Using the National (Nationwide) Inpatient Sample (NIS), we examined characteristics and mortality of primary cardiac hospitalizations in PAH from 2001 to 2014.

METHODS

Adult hospitalizations with any diagnosis code for PAH were identified. Primary cardiac disease was defined as a primary discharge diagnosis of congestive heart failure (CHF), pulmonary heart disease, coronary atherosclerosis, acute myocardial infarction, dysrhythmia, conduction disorder, cardiomyopathy or carditis, heart valve disorder, or cardiac arrest. Temporal trends, characteristics, and in-hospital mortality were analyzed.

RESULTS

From 2001 to 2014, there were 207,095 hospitalizations in PAH, of which 100,509 (48.5%) carried a primary cardiac diagnosis. Most primary cardiac hospitalizations in PAH were for CHF, and pneumonia was the most common primary non-cardiac diagnosis. Over the study period, primary cardiac hospitalizations in PAH fell from 52.9% to 41.4% (p < 0.001). CHF was the most frequent primary cardiac diagnosis associated with death, with sepsis representing the most common primary non-cardiac disease (1,226; 25.0%). Overall, the mortality in primary cardiac hospitalizations in PAH was 5.3% (vs. in primary non-cardiac, 6.9%, p < 0.001). On multivariable analysis, a primary cardiac discharge diagnosis remained associated with a decreased risk of death (odds ratio 0.85, p = 0.010).

CONCLUSION

Primary cardiac hospitalizations in PAH are common and are associated with decreased mortality compared to admissions for primary non-cardiac diagnoses.

Chronic Thromboembolic Pulmonary Hypertension-Management Strategies and Outcomes

Chronic thromboembolic pulmonary hypertension (CTEPH) is rare but complex pathophysiological disease with hallmark features of chronic thrombotic mechanical obstruction, right ventricular dysfunction, and secondary pulmonary arteriopathy. It increasingly is being understood that chronic infection/inflammation, abnormal fibrinolysis, and cytokines play an important role in pathogenesis such that only a subset of patients with pulmonary embolism develop CTEPH. Diagnosis remains challenging given the lack of early clinical signs and overlap with other cardiopulmonary conditions. Pulmonary endarterectomy is the surgical procedure of choice with good postoperative survival and functional outcomes, especially when done at high-volume centers with a multidisciplinary approach. There has been a resurgence of balloon pulmonary angioplasty (BPA) as salvage therapy for inoperable CTEPH or in its newfound hybrid role for persistent postoperative pulmonary hypertension with excellent 1-year and 3-year survival. Use of riociguat has shown promising improvements in functional outcomes up to 2 years after initiation. Endothelin receptor antagonists serve a supplemental role postoperatively or in inoperable CTEPH. The role of drug therapy preoperatively or in tandem with BPA is currently under investigation.

Aortic valve replacement with pulmonary hypertension: Meta-analysis of 70 676 patients

BACKGROUND AND AIM OF THE STUDY

We compared early and late outcomes of surgical aortic valve replacement (SAVR) in patients with aortic stenosis (AS) and pulmonary hypertension (PHT).

METHODS

We searched MEDLINE and EMBASE databases until July 2018 for studies comparing patients with AS and none, mild-moderate, or severe PHT undergoing SAVR. Random-effects meta-analysis was performed.

RESULTS

There were 12 observational studies with 70 676 patients with median follow-up 4.0 years (interquartile range, 2.6-4 years). Compared to patients with no PHT, patients with any PHT undergoing SAVR were older (mean difference [MD], 2.31 years; 95% confidence interval [CI], 1.38-3.23 years; P < .01), with greater comorbidities and reduced ejection fraction (MD, -4.36; 95%CI, -5.94 to -2.78; P < .01). Patients with any PHT had higher unadjusted (5.2% vs 2.4%; risk ratio [RR], 2.27; 95%CI, 2.04-2.53; P < .01) and adjusted (RR, 1.65; 95%CI, 1.28-2.14; P < .01) in-hospital mortality compared with no PHT. Severe (RR, 3.53; 95%CI, 1.46-8.54; P < .01) and mild-moderate PHT (RR, 2.13; 95%CI, 1.28-3.55; P < .01) were associated with higher unadjusted in-hospital mortality compared with no PHT. Any PHT was associated with a higher unadjusted risk of stroke (RR, 1.64; 95%CI, 1.42-1.90; P < .01), acute kidney injury (RR, 2.02; 95%CI, 1.50-2.72; P < .01), prolonged ventilation (RR, 1.62; 95%CI, 1.04-2.52; P = .03), and longer hospital stay (MD, 1.76 days; 95%CI, 0.57-2.95; P < .01). Severe (HR, 2.44; 95%CI, 1.60-3.72; P < .01) but not mild-moderate PHT (HR, 2.25; 95%CI, 0.91-5.59; P = .08) was associated with higher adjusted long-term mortality compared with no PHT.

CONCLUSIONS

Patients with severe AS and severe PHT had a significant increase in operative mortality and more than double the risk of long-term mortality following SAVR compared with patients with no PHT. Such patients may benefit from a less invasive transcatheter aortic valve intervention.

Effect of Radiation Doses to the Heart on Survival for Stereotactic Ablative Radiotherapy for Early-stage Non-Small-cell Lung Cancer: An Artificial Neural Network Approach

INTRODUCTION

The cardiac radiation dose is an important predictor of cardiac toxicity and overall survival (OS) for patients with locally advanced non-small-cell lung cancer (NSCLC). However, radiation-induced cardiac toxicity among patients with early-stage NSCLC who have undergone stereotactic ablative radiotherapy (SABR) has been less well-characterized. Our objective was to assess the associations between cardiac radiation dosimetry and OS in patients with early-stage NSCLC undergoing SABR.

MATERIALS AND METHODS

From 2009 to 2014, 153 patients with early-stage NSCLC had undergone SABR at a single institution. The maximum dose, mean dose, V_10Gy, V_25Gy, and V_50Gy to 15 cardiac substructures and the whole heart were analyzed for their association with OS using the Kaplan-Meier method. An artificial neural network (ANN) analysis was performed to modulate confounding behaviors of dosimetric variables to predict for OS.

RESULTS

A total of 112 patients were included in the present analysis. The right ventricle (RV) V_10Gy most negatively predicted for OS, such that patients who had received a RV V_10Gy dose < 4% had significantly longer OS than patients who had received a RV V_10Gy does > 4% (5.3 years vs. 2.4 years). On ANN analysis, 74 input features, including cardiac dosimetry parameters, predicted for survival with a test accuracy of 64.7%. A repeat ANN analysis using dosimetry to dose neutral structure confirmed the predictive power of cardiac dosimetry.

CONCLUSION

Cardiac dosimetry to subvolumes of the heart was associated with decreased OS in patients with early-stage NSCLC undergoing SABR. These data support the importance of minimizing the radiation dose to cardiac substructures. Further prioritizing the heart as an organ at risk might be warranted. Additionally, cardiac follow-up should be considered.

Cardiac Changes in Patients on Long-Term Parenteral Nutrition

Patients with short bowel syndrome (SBS) on long-term home parenteral nutrition (HPN) chronically receive high fluid volumes directly into the right atrium (RA) through the superior vena cava. We retrospectively evaluated cardiac function measured by routine transthoracic echocardiography (TTE) in a population of 26 SBS patients on long-term HPN and compared their data on echocardiograph-derived right heart structure and function, with those of a control group of 26 patients also bearing a central venous catheter (CVC) for other reasons. Results showed that body weight and BMI were significantly higher in the control group. The echocardiographic estimate of RA pressure was higher in HPN patients than in controls (p = 0.01). An increased estimate of RA pressure indicates the need to consider TTE in the follow-up of long-term HPN patients to detect functional impairment early.

Pulmonary Vascular Dynamics

The pulmonary circulation carries deoxygenated blood from the systemic veins through the pulmonary arteries to be oxygenated in the capillaries that line the walls of the pulmonary alveoli. The pulmonary circulation carries the cardiac output with a relatively low driving pressure, and so differs considerably in structure and function from the systemic circulation to maintain a low-resistance vascular system. The pulmonary circulation is often considered to be a quasi-static system in both experimental and computational studies of pulmonary perfusion and its matching to ventilation (air flow) for exchange. However, the system is highly dynamic, with cardiac output and regional perfusion changing with posture, exercise, and over time. Here we review this dynamic system, with a focus on understanding the physiology of pulmonary vascular dynamics across spatial and temporal scales, and the changes to these dynamics that are reflective of disease. © 2019 American Physiological Society. Compr Physiol 9:1081-1100, 2019.

Update on the Current Landscape of Transcatheter Options for Tricuspid Regurgitation Treatment

Most patients with severe tricuspid regurgitation lack treatment options because of prohibitive surgical risk. New transcatheter treatments under development and investigation might be able to address this unmet clinical need. This article gives an update on the landscape of devices for transcatheter tricuspid regurgitation treatment including different approaches (i.e. repair with leaflet approximation or annuloplasty and replacement using orthotopic or heterotopic valves) at different stages of development, from experimental to clinical trial. Repair devices such as the Cardioband or the MitraClip are leading the field with promising preliminary data and further trials are ongoing. However, with implantations of the Gate bioprosthesis, replacement devices are catching up. Potential advantages of different approaches and most recent data are discussed.

Inhaled levosimendan versus intravenous levosimendan in patients with pulmonary hypertension undergoing mitral valve replacement

Context:

Inhaled levosimendan may act as selective pulmonary vasodilator and avoid systemic side effects of intravenous levosimendan, which include decrease in systemic vascular resistance (SVR) and systemic hypotension, but with same beneficial effect on pulmonary artery pressure (PAP) and right ventricular (RV) function.

Aim:

The aim of this study was to compare the effect of inhaled levosimendan with intravenous levosimendan in patients with pulmonary hypertension undergoing mitral valve replacement.

Settings and Design:

The present prospective randomized comparative study was conducted in a tertiary care hospital.

Subjects and Methods:

Fifty patients were randomized into two groups (n = 25). Group A: Levosimendan infusion was started immediately after coming-off of cardiopulmonary bypass and continued for 24 h at 0.1 mcg/kg/min. Group B: Total dose of levosimendan which would be given through intravenous route over 24 h was calculated and then divided into four equal parts and administered through inhalational route 6^th hourly over 24 h. Hemodynamic profile (pulse rate, mean arterial pressure, pulmonary artery systolic pressure [PASP], SVR) and RV function were assessed immediately after shifting, at 1, 8, 24, and 36 h after shifting to recovery.

Statistical Analysis Used:

Intragroup analysis was done using paired student t-test, and unpaired student t-test was used for analysis between two groups.

Results:

PASP and RV-fractional area change (RV-FAC) were comparable in the two groups at different time intervals. There was a significant reduction in PASP and significant improvement in RV-FAC with both intravenous and inhalational levosimendan. SVR was significantly decreased with intravenous levosimendan, but no significant decrease in SVR was observed with inhalational levosimendan.

Conclusions:

Inhaled levosimendan is a selective pulmonary vasodilator. It causes decrease in PAP and improvement in RV function, without having a significant effect on SVR.

Changes in pulmonary artery systolic pressure and right ventricular function in patients with end-stage renal disease on maintenance dialysis

AIM

Pulmonary hypertension is common in patients with end-stage renal disease, and portends a poor prognosis. There are little data in this population, and previous studies have not evaluated quantitative changes in haemodynamics over time while on maintenance dialysis. This study sought to estimate changes in pulmonary artery systolic pressure (PASP) and right ventricular function over time, and to predict PASP change using clinical variables routinely available at time of initial measurement, in patients on maintenance dialysis.

METHODS

We retrospectively studied patients with end-stage renal disease at a university-affiliated dialysis centre who had two separate echocardiograms 1-4 years apart.

RESULTS

Seventy-six patients (65 haemodialysis, 11 peritoneal dialysis) were included. PASP was estimated by echocardiography. Baseline PASP was predicted by left-sided valvular disease, anaemia, COPD, left-ventricular mass index, and haemodialysis modality (P = 0.07 for modality). Average increase in PASP was 2.41 mmHg per year. Higher rates of PASP change were predicted by E/e' ratio by tissue doppler on echocardiogram, diabetes mellitus, low LV mass, and left-sided valvular heart disease (P = 0.07 for valvular disease). Patients with higher PASP had higher incidence of new-onset right ventricular dysfunction.

CONCLUSION

In patients with end-stage renal disease, PASP increases over time. Changes are moderately predictable. Higher PASP predicted development of right ventricular dysfunction.

Pathophysiology of right ventricular failure in acute pulmonary embolism and chronic thromboembolic pulmonary hypertension: a pictorial essay for the interventional radiologist

Pulmonary embolus (PE) is the third most common cause of cardiovascular death with more than 600,000 cases occurring in the USA per year. About 45% of patients with acute PE will have acute right ventricular failure, and up to 3.8% of patients will develop chronic thromboembolic pulmonary hypertension (CTEPH) with progressive, severe, chronic heart failure. The right ventricle (RV) is constructed to accommodate a low-resistance afterload. Increases in afterload from acute massive and submassive PE and CTEPH may markedly compromise the RV function leading to hemodynamic collapse and death. The purpose of this educational manuscript is to instruct on the pathophysiology of RV failure in massive and submassive PE and CTEPH. It is important to understand the pathophysiology of these diseases as it provides the rationale for therapeutic intervention by the Interventional Radiologist. We review here the pathophysiology of right ventricular (RV) failure in acute massive and submassive PE and CTEPH.

Structural and Biomechanical Adaptations of Right Ventricular Remodeling - in Pulmonary Arterial Hypertension - Reduces Left Ventricular Rotation During Contraction: A Computational Study

Pulmonary hypertension (PH) is a degenerative disease characterized by progressively increased right ventricular (RV) afterload that leads to ultimate functional decline [1]. Recent observational studies have documented a decrease in left ventricular (LV) torsion during ejection, with preserved LV ejection fraction (EF) in pediatric and adult PH patients [2-4]. The objective of this study was to develop a computational model of the bi-ventricular heart and use it to evaluate changes in LV torsion mechanics in response to mechanical, structural, and hemodynamic changes in the RV free-wall. The heart model revealed that LV apex rotation and torsion were decreased when increasing RV mechanical rigidity and during re-orientation of RV myocardial fibers. Furthermore, structural changes to the RV appear to have a notable impact on RV EF, but little influence on LV EF. Finally, RV pressure overload exponentially increased LV myocardial stress. The computational results found in this study are consistent with clinical observations in adult and pediatric PH patients, which reveal a decrease in LV torsion with preserved LV EF [3, 4]. Furthermore, discovered causes of decreased LV torsion are consistent with RV structural adaptations seen in PH rodent studies [5], which might also explain suspected stress-induced changes in LV myocardial gene/protein expression.

The role of echocardiographic parameters in predicting survival of patients with lung diseases referred for lung transplantation

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) show poor prognosis. The importance of left (LV) and right (RV) ventricular morphology and function in patients with end-stage lung diseases referred for lung transplantation (LT) is not well established.

OBJECTIVES

To assess whether LV and RV echocardiographic parameters influence survival of patients with IPF, COPD and other interstitial lung diseases (ILD) awaiting LT.

METHODS

In 65 patients (20 patients with COPD, 37 with IPF and 8 with other ILD), we performed transthoracic echocardiography and right heart catheterization. Echocardiographic parameters were assessed with regard to 1-year all-cause mortality.

RESULTS

The mortality rate was higher in patients with smaller dimensions of LV end-systolic (LVESD) and end-diastolic (LVEDD) diameter (HR 3.03, 95% CI 1.16-7.69, P = .023; and HR 2.9, 95% CI 1.16-7.14, P = .022; respectively), higher RV-to-LV (RV/LV-4CH) ratio (HR 7.6, 95% CI 1.6-29.5, P = .009) and RV proximal outflow tract (RVOT-PLAX) dilatation (HR 2.69, 95% CI 1.22-5.96, P = .015). These associations were independent of age, gender, body mass index, VC, FEV1% and pulmonary diagnosis. The subanalysis of IPF patients demonstrated that the smaller LVESD and LVEDD increased mortality rate (HR 15.0, 95% CI 2.87-89.72, P = .003; HR 4.95, 95% CI 1.5-15.5, P = .006; respectively). No such associations were found in the COPD patients.

CONCLUSION

LV echocardiographic parameters (LVESD or LVEDD) are useful in predicting survival in patients with end-stage lung diseases, mainly in IPF patients awaiting LT. Other parameters (RV/LV-4CH and RVOT-PLAX dilatation) may also influence survival.

MRI-derived Regional Biventricular Function in Patients with Chronic Thromboembolic Pulmonary Hypertension Before and After Pulmonary Endarterectomy

RATIONALE AND OBJECTIVES

The aim of this study was to assess regional myocardial function in patients with chronic thromboembolic hypertension (CTEPH) before and after successful pulmonary endarterectomy (PEA) using magnetic resonance imaging.

METHODS

Twenty-two patients with CTEPH underwent cardiac magnetic resonance imaging before and 12 (11, 17) days after PEA. Mean pulmonary artery pressure was evaluated preoperatively by right heart catheterization and during post-PEA intensive care unit-stay using a Swan-Ganz catheter. Biventricular peak systolic longitudinal, radial, circumferential strain and time-to-peak strain were obtained by tissue-tracking analysis.

RESULTS

Mean pulmonary artery pressure decreased (46 mm Hg (34.5, 55) to 24 mm Hg (16, 27); P < .0001) and stroke volume increased (P < .0001) after PEA. In the right ventricle (RV) peak radial strain increased in the anterior (P = .04) and in the inferior wall (P = .0012) and slightly missed statistical significance in the lateral wall (P = .051) and septum (P = .07). Circumferential strain increased in the lateral (P = .0002) and inferior wall of the RV (P = .03) and in the lateral as well as in the inferior wall of the left ventricle (P = .01; P = .03). Radial, longitudinal, and circumferential time-to-peak strain shortened (P < .0001) with resynchronization of the ventricles 12 days after PEA.

CONCLUSION

While biventricular resynchronization and recovery of global predominantly RV function was observed, regional circumferential function mainly improved in the lateral and inferior walls of both ventricles and regional radial function in the RV wall and septum 12 days after PEA, suggesting fibers primarily affected by myocardial stress in patients with CTEPH possibly need a relatively longer recovery time.

Echocardiography during preload stress for evaluation of right ventricular contractile reserve and exercise capacity in pulmonary hypertension

OBJECTIVES

Pulmonary hypertension (PH) is characterized by marked and sustained elevation of pulmonary vascular resistance and pulmonary artery pressure, and subsequent right-sided heart failure. Right ventricular (RV) function and exercise capacity have been recognized as important prognostic factors for PH. Our aim was to investigate RV contractile reserve and exercise capacity during a leg-positive pressure (LPP) maneuver.

METHODS

The study population comprised 43 PH patients and 17 normal controls. All patients underwent echocardiography at rest and during LPP stress. Exercise capacity was assessed by 6-minute walk distance for PH patients. RV relative wall thickness was calculated from dividing by RV free wall thickness by basal RV linear dimensions at end-diastole. RV function was calculated by averaging peak speckle-tracking longitudinal strain from the RV free wall. RV contractile reserve was assessed as the difference in RV free wall strain at rest and during LPP stress. Changes in left ventricular stroke volume (ΔSV) during LPP stress were also calculated.

RESULTS

ΔSV and RV contractile reserve of PH patients were significantly lower than of controls (3.6 ± 6.0 mL vs 8.5 ± 2.3 mL, and 8.2 ± 11.9% vs 14.5 ± 6.6%; both P < 0.01). RV contractile reserve of PH patients with ΔSV <3.3 mL was significantly lower than of PH patients with ΔSV >3.3 mL (3.9 ± 13.2% vs 12.3 ± 8.9%; P = 0.02). ΔSV had also significant correlation with 6-minute walk distance (r = 0.42, P = 0.006). Multivariate regression analysis showed that RV relative wall thickness was an independent determinant parameter of ΔSV during LPP stress for PH patients (β = 3.2, P = 0.003).

CONCLUSIONS

Preload stress echocardiography in response to LPP maneuver, a noninvasive and easy-to-use procedure for routine clinical use, proved to be useful for the assessment of RV contractile reserve and exercise capacity of PH patients.

Transcatheter Tricuspid Valve Replacement: Principles and Design

Tricuspid regurgitation (TR) may affect as much as 65-85% of the population with the prevalence of moderate-to-severe TR in the United States reported at greater than 1.6 million. However, only 8,000 tricuspid valve operations are performed annually in the United States. As severe TR is associated with poor outcomes, there is an unmet clinical need for surgical or percutaneous transcatheter based treatment of TR. Over the last two decades there have been significant developments in percutaneous transcatheter based therapies for valvular disease. However, this progress has not been mirrored for the tricuspid valve until recently; we are now at a cross-roads of new transcatheter devices becoming available for treatment of TR. In this review, we discuss the principles of performing transcatheter tricuspid valve replacement, analyze the devices that can be utilized and outline the challenges related to this procedure.

Echocardiographic evaluation of the right ventricular dimension and systolic function in dogs with pulmonary hypertension

Background

Right ventricular (RV) enlargement and dysfunction are associated with prognosis in humans with pulmonary hypertension (PH).

Hypothesis/Objectives

To assess RV size and systolic function in dogs with PH and to determine if they are associated with disease severity and right‐sided congestive heart failure (R‐CHF).

Animals

89 dogs with PH and 74 healthy dogs.

Methods

Prospective observational study. PH was classified according to the tricuspid regurgitation pressure gradient. RV end‐diastolic area (RVEDA) index was calculated as RVEDA divided by body surface area. RV systolic function was assessed with the tricuspid annular plane systolic excursion (TAPSE) and the RV fractional area change (FAC) normalized for body weight (TAPSEn and FACn, respectively).

Results

RVEDA index was higher in dogs with moderate PH (10.8 cm²/m²; range, 6.2‐14.4 cm²/m²) and severe PH (12.4 cm²/m²; range, 7.7‐21.4 cm²/m²) than in those with mild PH (8.4 cm²/m²; range, 4.8‐11.6 cm²/m²) and control dogs (8.5 cm²/m²; range, 2.8‐11.6 cm²/m²; P < .001). RVEDA index was significantly higher in dogs with R‐CHF (13.7 cm²/m²; range, 11.0‐21.4 cm²/m²) than in dogs without R‐CHF (9.4 cm²/m²; range, 4.8‐17.1 cm²/m²; P < .001). The severity of tricuspid regurgitation (TR) was the only independent predictor of the RVEDA index (P < .001). TAPSEn and FACn were not significantly different among varying degrees of PH severity and between dogs with and without R‐CHF.

Conclusions and Clinical Importance

The RVEDA index can be used to evaluate RV size in dogs. It can provide additional information in dogs with PH and predict R‐CHF. Severity of TR is the main determinant of RV enlargement in dogs with PH.

Coronary artery bypass graft surgery complications: A review for emergency clinicians

INTRODUCTION

Coronary artery bypass graft (CABG) surgery remains a high-risk procedure, and many patients require emergency department (ED) management for complications after surgery.

OBJECTIVE

This narrative review provides an evidence-based summary of the current data for the emergency medicine evaluation and management of post-CABG surgery complications.

DISCUSSION

While there has been a recent decline in all cardiac revascularization procedures, there remains over 200,000 CABG surgeries performed in the United States annually, with up to 14% of these patients presenting to the ED within 30 days of discharge with post-operative complications. Risk factors for perioperative mortality and morbidity after CABG surgery can be divided into three categories: patient characteristics, clinician characteristics, and postoperative factors. Emergency physicians will be faced with several postoperative complications, including sternal wound infections, pneumonia, thromboembolic phenomena, graft failure, atrial fibrillation, pulmonary hypertension, pericardial effusion, strokes, renal injury, gastrointestinal insults, and hemodynamic instability. Critical patients should be evaluated in the resuscitation bay, and consultation with the primary surgical team is needed, which improves patient outcomes. This review provides several guiding principles for management of acute complications. Understanding these complications and an approach to the management of hemodynamic instability is essential to optimizing patient care.

CONCLUSIONS

Postoperative complications of CABG surgery can result in significant morbidity and mortality. Physicians must rapidly diagnose these conditions while evaluating for other diseases. Early surgical consultation is imperative, as is optimizing the patient's hemodynamics, including preload, heart rate, cardiac rhythm, contractility, and afterload.

Inflammatory Mediators Drive Adverse Right Ventricular Remodeling and Dysfunction and Serve as Potential Biomarkers

Adverse right ventricular (RV) remodeling leads to ventricular dysfunction and failure that represents an important determinant of outcome in patients with pulmonary hypertension (PH). Recent evidence indicates that inflammatory activation contributes to the pathogenesis of adverse RV remodeling and dysfunction. It has been shown that accumulation of inflammatory cells such as macrophages and mast cells in the right ventricle is associated with maladaptive RV remodeling. In addition, inhibition of inflammation in animal models of RV failure ameliorated RV structural and functional impairment. Furthermore, a number of circulating inflammatory mediators have been demonstrated to be associated with RV performance. This work reviews the role of inflammation in RV remodeling and dysfunction and discusses anti-inflammatory strategies that may attenuate adverse structural alterations while promoting improvement of RV function.

Evaluation and Management of Right-Sided Heart Failure: A Scientific Statement From the American Heart Association

Background and Purpose:

The diverse causes of right-sided heart failure (RHF) include, among others, primary cardiomyopathies with right ventricular (RV) involvement, RV ischemia and infarction, volume loading caused by cardiac lesions associated with congenital heart disease and valvular pathologies, and pressure loading resulting from pulmonic stenosis or pulmonary hypertension from a variety of causes, including left-sided heart disease. Progressive RV dysfunction in these disease states is associated with increased morbidity and mortality. The purpose of this scientific statement is to provide guidance on the assessment and management of RHF.

Methods:

The writing group used systematic literature reviews, published translational and clinical studies, clinical practice guidelines, and expert opinion/statements to summarize existing evidence and to identify areas of inadequacy requiring future research. The panel reviewed the most relevant adult medical literature excluding routine laboratory tests using MEDLINE, EMBASE, and Web of Science through September 2017. The document is organized and classified according to the American Heart Association to provide specific suggestions, considerations, or reference to contemporary clinical practice recommendations.

Results:

Chronic RHF is associated with decreased exercise tolerance, poor functional capacity, decreased cardiac output and progressive end-organ damage (caused by a combination of end-organ venous congestion and underperfusion), and cachexia resulting from poor absorption of nutrients, as well as a systemic proinflammatory state. It is the principal cause of death in patients with pulmonary arterial hypertension. Similarly, acute RHF is associated with hemodynamic instability and is the primary cause of death in patients presenting with massive pulmonary embolism, RV myocardial infarction, and postcardiotomy shock associated with cardiac surgery. Functional assessment of the right side of the heart can be hindered by its complex geometry. Multiple hemodynamic and biochemical markers are associated with worsening RHF and can serve to guide clinical assessment and therapeutic decision making. Pharmacological and mechanical interventions targeting isolated acute and chronic RHF have not been well investigated. Specific therapies promoting stabilization and recovery of RV function are lacking.

Conclusions:

RHF is a complex syndrome including diverse causes, pathways, and pathological processes. In this scientific statement, we review the causes and epidemiology of RV dysfunction and the pathophysiology of acute and chronic RHF and provide guidance for the management of the associated conditions leading to and caused by RHF.

Optimal right heart filling pressure in acute respiratory distress syndrome determined by strain echocardiography

INTRODUCTION

Right ventricular (RV) systolic dysfunction is common in acute respiratory distress syndrome (ARDS). While preload optimization is crucial in its management, dynamic fluid responsiveness indices lack reliability, and there is no consensus on target central venous pressure (CVP). We analyzed the utility of RV free wall longitudinal strain (RVFWS) in the estimation of optimal RV filling pressure in ARDS.

METHODS

A retrospective cross-sectional analysis of clinical data and echocardiograms of patients with ARDS was performed. Tricuspid annular plane systolic excursion (TAPSE), tricuspid peak systolic velocity (S'), RV fractional area change (RVFAC), RVFWS, CVP, systolic pulmonary artery pressure (SPAP), and left ventricular ejection fraction (LVEF) were measured.

RESULTS

Fifty-one patients with moderate-severe ARDS were included. There were inverse correlations between CVP and TAPSE, S', RVFAC, RVFWS, and LVEF. The most significant was with RVFWS (r:.74, R² :.55, P:.00001). Direct correlations with creatinine and lactate were noted. Receiver operating characteristic analysis showed that RVFWS -21% (normal reference value) was associated with CVP: 13 mm Hg (AUC: 0.92, 95% CI: 0.83-1.00). Regression model analysis of CVP, and RVFWS interactions established an RVFWS range from -18% to -24%. RVFWS -24% corresponded to CVP: 11 mm Hg and RVFWS -18% to CVP: 15 mm Hg. Beyond a CVP of 15 mm Hg, biventricular systolic dysfunction rapidly ensues.

CONCLUSIONS

Our data are the first to show that an RV filling pressure of 13±2 mm Hg-as by CVP-correlates with optimal RV mechanics as evaluated by strain echocardiography in patients with moderate-severe ARDS.

Molecular pathogenesis and current pathology of pulmonary hypertension

Following its initial description over a century ago, pulmonary arterial hypertension (PAH) continues to challenge researchers committed to understanding its pathobiology and finding a cure. The last two decades have seen major developments in our understanding of the genetics and molecular basis of PAH that drive cells within the pulmonary vascular wall to produce obstructive vascular lesions; presently, the field of PAH research has taken numerous approaches to dissect the complex amalgam of genetic, molecular and inflammatory pathways that interact to initiate and drive disease progression. In this review, we discuss the current understanding of PAH pathology and the role that genetic factors and environmental influences share in the development of vascular lesions and abnormal cell function. We also discuss how animal models can assist in elucidating gene function and the study of novel therapeutics, while at the same time addressing the limitations of the most commonly used rodent models. Novel experimental approaches based on application of next generation sequencing, bioinformatics and epigenetics research are also discussed as these are now being actively used to facilitate the discovery of novel gene mutations and mechanisms that regulate gene expression in PAH. Finally, we touch on recent discoveries concerning the role of inflammation and immunity in PAH pathobiology and how they are being targeted with immunomodulatory agents. We conclude that the field of PAH research is actively expanding and the major challenge in the coming years is to develop a unified theory that incorporates genetic and mechanistic data to address viable areas for disease modifying drugs that can target key processes that regulate the evolution of vascular pathology of PAH.

Macitentan in Pulmonary Arterial Hypertension: A Focus on Combination Therapy in the SERAPHIN Trial

SERAPHIN was a double-blind, placebo-controlled, event-driven phase III trial that evaluated the effects of long-term treatment with macitentan, an oral endothelin receptor antagonist, in patients with pulmonary arterial hypertension (PAH). The majority of patients were receiving PAH therapy at enrollment, providing the opportunity to evaluate the efficacy and safety of macitentan in combination with other PAH therapies (predominantly phosphodiesterase type 5 inhibitors [PDE-5i]). In patients receiving background therapy, macitentan reduced the risk of morbidity/mortality by 38% compared with placebo (hazard ratio [HR] 0.62; 95% confidence level [CL] 0.43-0.89; p = 0.009). Furthermore, patients receiving macitentan and background therapy had a 37% reduction in the risk of being hospitalized for PAH (HR 0.63; 95% CL 0.41-0.96) compared with patients receiving background therapy only (placebo arm). Macitentan treatment in combination with background therapy was also associated with improvements in exercise capacity, functional class, cardiopulmonary hemodynamics, and health-related quality of life compared with background therapy alone. The safety profile of macitentan as part of a combination therapy regimen was consistent with that of macitentan in the overall SERAPHIN population. The SERAPHIN study has provided evidence that combination therapy with macitentan and a PDE-5i is effective and well tolerated in the management of PAH. Based on these data, and those from subsequent long-term trials, combination therapy is increasingly recognized as an important treatment option for improving long-term outcomes in PAH.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00660179.

The Minimal Important Difference in Borg Dyspnea Score in Pulmonary Arterial Hypertension

RATIONALE

Despite therapeutic advances, pulmonary arterial hypertension remains a disease without a cure. Focusing on symptoms, such as dyspnea, is an important part of assessing response to therapy.

OBJECTIVES

To determine the minimal important differences for the Borg dyspnea score and the Borg fatigue score in adult patients undergoing initial therapy for pulmonary arterial hypertension.

METHODS

We studied 129 patients enrolled between 2003 and 2013 in the Pulmonary Arterial Hypertension Program registry at Johns Hopkins University Hospital in Baltimore, Maryland. We analyzed baseline demographics, clinical characteristics, 6-minute-walk test distance, and Borg dyspnea and fatigue scores at baseline and at follow up 3 months after initiation of pulmonary arterial hypertension therapy. The minimal important differences for the Borg dyspnea and fatigue scores were determined using distributional and anchor-based methods, using 6-minute-walk test distance as the anchor.

MEASUREMENTS AND MAIN RESULTS

Most subjects were in New York Heart Association functional class II or III and had moderate to severe pulmonary arterial hypertension. The baseline Borg dyspnea score was 3.4 ± 1.9 units; the baseline Borg fatigue score was 2.8 ± 2.2 units. After therapy, the average change in the dyspnea score was -0.16 ± 1.9 units and the average change in the fatigue score was -0.21 ± 2.4 units. Using distributional methods, the minimum important difference for Borg dyspnea score ranged from 0.7 to 1.24 units and for Borg fatigue score ranged from 0.73 to 1.39 units. Using anchor-based methods, the minimum important difference for the Borg dyspnea scales was 0.36; this could not be calculated for the Borg fatigue score.

CONCLUSIONS

Using distributional and anchor-based methods, we estimate the minimum important difference for Borg dyspnea scale in pulmonary arterial hypertension is approximately 0.9 units. Using distributional methods only, we estimate the minimum important difference for the Borg fatigue scale is around 1 unit. Further studies are needed to determine the clinical utility of these scores in patients with pulmonary arterial hypertension.

Effect of Riociguat and Sildenafil on Right Heart Remodeling and Function in Pressure Overload Induced Model of Pulmonary Arterial Banding

Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by remodeling of the pulmonary vasculature and a rise in right ventricular (RV) afterload. The increased RV afterload leads to right ventricular failure (RVF) which is the reason for the high morbidity and mortality in PAH patients. The objective was to evaluate the therapeutic efficacy and antiremodeling potential of the phosphodiesterase type 5 (PDE5) inhibitor sildenafil and the soluble guanylate cyclase stimulator riociguat in a model of pressure overload RV hypertrophy induced by pulmonary artery banding (PAB). Mice subjected to PAB, one week after surgery, were treated with either sildenafil (100 mg/kg/d, n = 5), riociguat (30 mg/kg/d, n = 5), or vehicle (n = 5) for 14 days. RV function and remodeling were assessed by right heart catheterization, magnetic resonance imaging (MRI), and histomorphometry. Both sildenafil and riociguat prevented the deterioration of RV function, as determined by a decrease in RV dilation and restoration of the RV ejection fraction (EF). Although both compounds did not decrease right heart mass and cellular hypertrophy, riociguat prevented RV fibrosis induced by PAB. Both compounds diminished TGF-beta1 induced collagen synthesis of RV cardiac fibroblasts in vitro. Treatment with either riociguat or sildenafil prevented the progression of pressure overload-induced RVF, representing a novel therapeutic approach.

Right Ventricular Perfusion

Regulation of blood flow to the right ventricle differs significantly from that to the left ventricle. The right ventricle develops a lower systolic pressure than the left ventricle, resulting in reduced extravascular compressive forces and myocardial oxygen demand. Right ventricular perfusion has eight major characteristics that distinguish it from left ventricular perfusion: (1) appreciable perfusion throughout the entire cardiac cycle; (2) reduced myocardial oxygen uptake, blood flow, and oxygen extraction; (3) an oxygen extraction reserve that can be recruited to at least partially offset a reduction in coronary blood flow; (4) less effective pressure–flow autoregulation; (5) the ability to downregulate its metabolic demand during coronary hypoperfusion and thereby maintain contractile function and energy stores; (6) a transmurally uniform reduction in myocardial perfusion in the presence of a hemodynamically significant epicardial coronary stenosis; (7) extensive collateral connections from the left coronary circulation; and (8) possible retrograde perfusion from the right ventricular cavity through the Thebesian veins. These differences promote the maintenance of right ventricular oxygen supply–demand balance and provide relative resistance to ischemia-induced contractile dysfunction and infarction, but they may be compromised during acute or chronic increases in right ventricle afterload resulting from pulmonary arterial hypertension. Contractile function of the thin-walled right ventricle is exquisitely sensitive to afterload. Acute increases in pulmonary arterial pressure reduce right ventricular stroke volume and, if sufficiently large and prolonged, result in right ventricular failure. Right ventricular ischemia plays a prominent role in these effects. The risk of right ventricular ischemia is also heightened during chronic elevations in right ventricular afterload because microvascular growth fails to match myocyte hypertrophy and because microvascular dysfunction is present. The right coronary circulation is more sensitive than the left to α-adrenergic–mediated constriction, which may contribute to its greater propensity for coronary vasospasm. This characteristic of the right coronary circulation may increase its vulnerability to coronary vasoconstriction and impaired right ventricular perfusion during administration of α-adrenergic receptor agonists.

Valvular heart disease and anaesthesia

Valvular heart disease presents as mixed spectrum lesion in healthcare settings in the third-world and developing countries. Rheumatic heart disease still forms the bulk of the aetiopathology of valve lesions. Mitral and aortic valve lesions top the list of valvular pathology. A thorough understanding of the pathophysiology of valvular heart disease is essential while planning anaesthesia and perioperative care for such patients. Meticulous use of optimal fluids, close monitoring of the changing haemodynamics and avoidance of situations that can cause major reduction of cardiac output and fluid shifts are mandatory to achieve good clinical outcome. We searched MEDLINE using combinations of the following: anaesthesia, aortic, mitral, regurgitation, stenosis and valvular heart disease. We also hand searched textbooks and articles on valvular heart disease and anaesthesia. This article mainly focuses on the understanding the pathophysiology of valvular heart disease in patients presenting for non-cardiac surgeries in secondary and tertiary care setting.

Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance

Background

Right ventricular (RV) diastolic function has been associated with outcomes for patients with pulmonary hypertension; however, the relationship between biomechanics and hemodynamics in the right ventricle has not been studied.

Methods and Results

Rat models of RV pressure overload were obtained via pulmonary artery banding (PAB; control, n=7; PAB, n=5). At 3 weeks after banding, RV hemodynamics were measured using a conductance catheter. Biaxial mechanical properties of the RV free wall myocardium were obtained to extrapolate longitudinal and circumferential elastic modulus in low and high strain regions (E₁ and E₂, respectively). Hemodynamic analysis revealed significantly increased end‐diastolic elastance (E_ed) in PAB (control: 55.1 mm Hg/mL [interquartile range: 44.7–85.4 mm Hg/mL]; PAB: 146.6 mm Hg/mL [interquartile range: 105.8–155.0 mm Hg/mL]; P=0.010). Longitudinal E₁ was increased in PAB (control: 7.2 kPa [interquartile range: 6.7–18.1 kPa]; PAB: 34.2 kPa [interquartile range: 18.1–44.6 kPa]; P=0.018), whereas there were no significant changes in longitudinal E₂ or circumferential E₁ and E₂. Last, wall stress was calculated from hemodynamic data by modeling the right ventricle as a sphere: stress=Pressure×radius2×thickness.

Conclusions

RV pressure overload in PAB rats resulted in an increase in diastolic myocardial stiffness reflected both hemodynamically, by an increase in E_ed, and biomechanically, by an increase in longitudinal E₁. Modest increases in tissue biomechanical stiffness are associated with large increases in E_ed. Hemodynamic measurements of RV diastolic function can be used to predict biomechanical changes in the myocardium.

Evidence of apoptosis in right ventricular dysfunction in rheumatic mitral valve stenosis

Background & objectives:

Right ventricular (RV) dysfunction is one of the causes of morbidity and mortality in valvular heart disease. The phenomenon of apoptosis, though rare in cardiac muscle may contribute to loss of its function. Role of apoptosis in RV in patients with rheumatic valvular heart disease is investigated in this study.

Methods:

Patients with rheumatic mitral valve stenosis formed two groups based on RV systolic pressure (RVSP) as RVSP <40 mmHg (group I, n=9) and RVSP ≥40 mmHg (group II, n=30). Patients having atrial septal defect (ASD) with RVSP <40 mmHg served as control (group III, n=15). Myocardial performance index was assessed for RV function. Real-time polymerase chain reaction was performed on muscle biopsy procured from RV to assess expression of pro-apoptotic genes (Bax, cytochrome c, caspase 3 and Fas) and anti-apoptotic genes (Bcl-2). Apoptosis was confirmed by histopathology and terminal deoxynucleotide-transferase-mediated dUTP nick end labelling.

Results:

Group II had significant RV dysfunction compared to group I (P=0.05) while caspase 3 (P=0.01) and cytochrome c (P=0.03) were expressed excessively in group I. When group I was compared to group III (control), though there was no difference in RV function, a highly significant expression of pro-apoptotic genes was observed in group I (Bax, P=0.02, cytochrome c=0.001 and caspase 3=0.01). There was a positive correlation between pro-apoptotic genes. Nuclear degeneration was present conforming to apoptosis in valve disease patients (groups I and II) while it was absent in patients with ASD.

Interpretation & conclusion:

Our findings showed evidence of apoptosis in RV of patients with valvular heart disease. Apoptosis was set early in the course of rheumatic valve disease even with lower RVSP, followed by RV dysfunction; however, expression of pro-apoptotic genes regressed.

Chronic Thromboembolic Pulmonary Hypertension: Pearls and Pitfalls of Diagnosis

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by chronic obstruction of major pulmonary arteries by organized thromboembolic material. Untreated CTEPH can result in pulmonary hypertension and eventually right heart failure, yet it is the only form of pulmonary hypertension that is potentially curable with surgical or catheter-based intervention. While early diagnosis is key to increasing the likelihood of successful treatment, CTEPH remains largely underdiagnosed. This article reviews the role of echocardiogram, ventilation/perfusion scan, and other available modalities in the diagnosis of CTEPH.

Maternal nutrient restriction during pregnancy and lactation leads to impaired right ventricular function in young adult baboons

KEY POINTS

Maternal nutrient restriction induces intrauterine growth restriction (IUGR) and leads to heightened cardiovascular risks later in life. We report right ventricular (RV) filling and ejection abnormalities in IUGR young adult baboons using cardiac magnetic resonance imaging. Both functional and morphological indicators of poor RV function were seen, many of which were similar to effects of ageing, but also with a few key differences. We observed more pronounced RV changes compared to our previous report of the left ventricle, suggesting there is likely to be a component of isolated RV abnormality in addition to expected haemodynamic sequelae from left ventricular dysfunction. In particular, our findings raise the suspicion of pulmonary hypertension after IUGR. This study establishes that IUGR also leads to impairment of the right ventricle in addition to the left ventricle classically studied.

ABSTRACT

Maternal nutrient restriction induces intrauterine growth restriction (IUGR), increasing later life chronic disease including cardiovascular dysfunction. Our left ventricular (LV) CMRI studies in IUGR baboons (8 M, 8 F, 5.7 years - human equivalent approximately 25 years), control offspring (8 M, 8 F, 5.6 years), and normal elderly (OLD) baboons (6 M, 6 F, mean 15.9 years) revealed long-term LV abnormalities in IUGR offspring. Although it is known that right ventricular (RV) function is dependent on LV health, the IUGR right ventricle remains poorly studied. We examined the right ventricle with cardiac magnetic resonance imaging in the same cohorts. We observed decreased ejection fraction (49 ± 2 vs. 33 ± 3%, P < 0.001), cardiac index (2.73 ± 0.27 vs. 1.89 ± 0.20 l min-1 m-2 , P < 0.05), early filling rate/body surface area (BSA) (109.2 ± 7.8 vs. 44.6 ± 7.3 ml s-1  m-2 , P < 0.001), wall thickening (61 ± 3 vs. 44 ± 5%, P < 0.05), and longitudinal shortening (26 ± 3 vs. 15 ± 2%, P < 0.01) in IUGR animals with increased chamber volumes. Many, but not all, of these changes share similarities to normal older animals. Our findings suggest IUGR-induced pulmonary hypertension should be further investigated and that atrial volume, pulmonic outflow and interventricular septal motion may provide valuable insights into IUGR cardiovascular physiology. Overall, our findings reaffirm that gestational and neonatal challenges can result in long-term programming of poor offspring cardiovascular health. To our knowledge, this is the first study reporting IUGR-induced programmed adult RV dysfunction in an experimental primate model.

Cardiac dysfunction in congenital diaphragmatic hernia: Pathophysiology, clinical assessment, and management

Cardiac dysfunction is an important consequence of pulmonary hypertension in congenital diaphragmatic hernia and a determinant of disease severity. Increased afterload leads to right ventricular dilatation and diastolic dysfunction. Septal displacement and dysfunction impair left ventricular function, which may also be compromised by fetal hypoplasia. Biventricular failure contributes to systemic hypotension and hypoperfusion. Early and regular echocardiographic assessment of cardiac function and pulmonary artery pressure can guide therapeutic decision-making, including choice and timing of pulmonary vasodilators, cardiotropes, ECMO, and surgery.

Favorable Evolution of a Patient with Thromboembolic Pulmonary Hypertension

We present a case of severe thromboembolic pulmonary hypertension in a patient with history of recurrent deep vein thrombosis and pulmonary restrictive disease due to pulmonary and vertebral tuberculosis in young adulthood. He was considered not eligible in the National Program for Primary Pulmonary Hypertension, being referred for thoracic surgery, but he was considered unfit for thrombendarterectomy. Despite guidelines, we administered him specific medical therapy (phosphodiesterase-5 inhibitors and endothelin receptor antagonists). His clinical evolution was satisfactory, with increasing effort tolerance and decreasing need for ambulatory oxigenotherapy.

Impact of Pulmonary Hemodynamics and Ventricular Interdependence on Left Ventricular Diastolic Function in Children With Pulmonary Hypertension

BACKGROUND

Through ventricular interdependence, pulmonary hypertension (PH) induces left ventricular (LV) dysfunction. We hypothesized that pediatric PH patients have LV diastolic dysfunction, related to adverse pulmonary hemodynamics, leftward septal shift, and prolonged right ventricular systole.

METHODS AND RESULTS

Echocardiography was prospectively performed at 2 institutions in 54 pediatric PH patients during cardiac catheterization and in 54 matched controls. Diastolic LV measures including myocardial deformation were assessed by echocardiography. PH patients had evidence of LV diastolic dysfunction, most consistent with impaired LV relaxation, though some features of reduced ventricular compliance were present. PH patients demonstrated the following: reduced mitral E velocity and inflow duration, mitral E' and E'/A', septal E' and A', pulmonary vein S and D wave velocities, and LV basal global early diastolic circumferential strain rate and increased mitral E deceleration time, LV isovolumic relaxation time, mitral E/E', and pulmonary vein A wave duration. PH patients demonstrated leftward septal shift and prolonged right ventricular systole, both known to affect LV diastole. These changes were exacerbated in severe PH. There were no statistically significant differences in diastolic measures between patients with and without a shunt and minimal differences between patients with and without congenital heart disease. Multiple echocardiographic LV diastolic parameters demonstrated weak-to-moderate correlations with invasively determined PH severity, leftward septal shift, and prolonged right ventricular systole.

CONCLUSIONS

Pediatric PH patients exhibit LV diastolic dysfunction most consistent with impaired relaxation and reduced myocardial deformation, related to invasive hemodynamics, leftward septal shift, and prolonged right ventricular systole.