Pulmonary hypertension: diagnosis and management

Relationship Between Pulmonary Artery Pressure and Inflammation Parameters

Background Inflammation can play a role in the development and progression of pulmonary hypertension (PHT). In this study, inflammatory parameters were compared in congestive heart failure (CHF) patients with and without PHT. The relationship between pulmonary artery pressure (PAP) and inflammatory parameters was investigated. Materials and methods Out of 80 CHF patients, 40 had PHT. The patients' age, gender, smoking status, comorbidities such as diabetes mellitus (DM) and hypertension (HT), and mortality rates were recorded. Inflammatory parameters were recorded. Results The mean age of the PHT group was 64.38 ± 9.17 and the mean age of the non-PHT group was 64.70 ± 8.99. There were 23 men and 17 women in the PHT group, and there were 21 men and 19 women in the non-PHT group. There was no significant difference between the two groups in terms of mean age and gender distribution (p = 0.874 and p = 0.653). Accordingly, the C-reactive protein to albumin ratio (CAR) value was statistically significantly higher in PHT patients (p = 0.023). The eosinophil count was found to be significantly higher in non-PHT patients (p = 0.015). Accordingly, a significant correlation was detected between CAR and PAP (r = 0.392 and p < 0.001). Conclusion In this study, the positive correlation between PAP and CAR and the significantly higher CAR value in PHT patients indicate the presence of inflammation in PHT patients. Studies on the relationship between inflammation and mortality in PHT patients may contribute more to the literature in the future.

Hemodynamic Effects of Ketone Bodies in Patients With Pulmonary Hypertension

Background Pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) are debilitating diseases with a high mortality. Despite emerging treatments, pulmonary vascular resistance frequently remains elevated. However, the ketone body 3-hydroxybutyrate (3-OHB) may reduce pulmonary vascular resistance in these patients. Hence, the aim was to assess the hemodynamic effects of 3-OHB in patients with PAH or CTEPH. Methods and Results We enrolled patients with PAH (n=10) or CTEPH (n=10) and residual pulmonary hypertension. They received 3-OHB infusion and placebo (saline) for 2 hours in a randomized crossover study. Invasive hemodynamic and echocardiography measurements were performed. Furthermore, we investigated the effects of 3-OHB on the right ventricle of isolated hearts and isolated pulmonary arteries from Sprague-Dawley rats. Ketone body infusion increased circulating 3-OHB levels from 0.5±0.5 to 3.4±0.7 mmol/L (P<0.001). Cardiac output improved by 1.2±0.1 L/min (27±3%, P<0.001), and right ventricular annular systolic velocity increased by 1.4±0.4 cm/s (13±4%, P=0.002). Pulmonary vascular resistance decreased by 1.3±0.3 Wood units (18%±4%, P<0.001) with no significant difference in response between patients with PAH and CTEPH. In the rat studies, 3-OHB administration was associated with decreased pulmonary arterial tension compared with saline administration (maximal relative tension difference: 12±2%, P<0.001) and had no effect on right ventricular systolic pressures (P=0.63), whereas pressures rose at a slower pace (dP/dtmax, P=0.02). Conclusions In patients with PAH or CTEPH, ketone body infusion improves cardiac output and decreases pulmonary vascular resistance. Experimental rat studies support that ketone bodies relax pulmonary arteries. Long-term studies are warranted to assess the clinical role of hyperketonemia. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04615754.

Pulmonary Hypertension, an Echo Assessment: Is it Arterial or Venous?

Introduction

Pulmonary hypertension (PH) is characterized by pulmonary vascular remodeling, right heart failure, and reduced survival. PH can be PH without left ventricular (LV) dysfunction - pulmonary arterial hypertension (PAH) - (Dana point Class I) and PH with LV dysfunction - pulmonary venous hypertension (PVH) - (Dana point Class II). Whatever the underlying cardiac disease, the presence of PH in patients with heart failure is associated with poor prognosis. Right ventricular dysfunction by ventricular interdependence can cause LV dysfunction.

Objective

We aim to provide a distinction between PAH and PVH by echocardiography.

Methods

Retrospective cross-sectional single-center data of 1075 subjects having PH as defined by echocardiography was collected. These were segregated into mild, moderate, and severe categories. The same cohort of PH subjects was also segregated by E/e' derived pulmonary capillary wedge pressure (PCWP) values. Echocardiographic measurements and effort tolerance in Mets were analyzed. Data for 707 normal subjects were taken from an earlier published study on normative echocardiographic measurements of healthy Indians.

Results

Our findings show that PAH and PVH can be distinguished using PCWP value >15 mmHg obtained by applying Nagueh's formulaon E/e'.

Conclusion

We recommend that PCWP derived from E/e' should be reported with pulmonary artery systolic pressure measurement to distinguish between PAH and PVH.

Can self-compassion help us better understand the impact of pulmonary hypertension on those with the condition and their carers? A cross-sectional analysis

Pulmonary hypertension (PH) can have a multifaced impact both on the affected individual and close family members. However there are relatively few studies that have sought to identify potential protective factors. Individual differences in ability to be self-compassionate are known to be implicated in adjustment in other long-term conditions and are now featuring in the provision of care for a number of conditions. This is a cross-sectional study that investigated the relationship between self-compassion, demographic, PH-related information, and measures of psychosocial functioning in adults with PH (n = 65) and caregivers (n = 29). Individuals with PH and caregivers of someone with PH completed self-report measures on demographic and clinical factors, anxiety, depression, self-compassion, and in those with PH, health-related quality of life, and in carers, caregiver burden. Data were analyzed using hierarchical regression analyses. Surprisingly, participants with PH and caregivers did not significantly differ on rates of depression (p = 0.19) or anxiety (p = 0.57) with both scoring relatively high. Components of self-compassion were associated with psychological functioning in both individuals and caregivers. Greater self-compassion was associated with fewer symptoms of anxiety and depression, and greater health-related quality of life in individuals with PH and lower burden in caregivers. More specifically, multiple regression analyses revealed after controlling for age, gender, and duration of PH, self-compassion was a significant predictor of anxiety and depression in people with PH, and of anxiety and caregiver burden in carers. These findings add to the evidence base indicating that there can be a range of burdens experienced by both people living with PH and their wider families. Further, this study uniquely suggests that psychological and supportive interventions that seek to build self-compassion may be useful to develop and test in this clinical group.

Methylation-mediated silencing of PTPRD induces pulmonary hypertension by promoting pulmonary arterial smooth muscle cell migration via the PDGFRB/PLCγ1 axis

OBJECTIVE

Pulmonary hypertension is a lethal disease characterized by pulmonary vascular remodeling and is mediated by abnormal proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs). Platelet-derived growth factor BB (PDGF-BB) is the most potent mitogen for PASMCs and is involved in vascular remodeling in pulmonary hypertension development. Therefore, the objective of our study is to identify novel mechanisms underlying vascular remodeling in pulmonary hypertension.

METHODS

We explored the effects and mechanisms of PTPRD downregulation in PASMCs and PTPRD knockdown rats in pulmonary hypertension induced by hypoxia.

RESULTS

We demonstrated that PTPRD is dramatically downregulated in PDGF-BB-treated PASMCs, pulmonary arteries from pulmonary hypertension rats, and blood and pulmonary arteries from lung specimens of patients with hypoxic pulmonary arterial hypertension (HPAH) and idiopathic PAH (iPAH). Subsequently, we found that PTPRD was downregulated by promoter methylation via DNMT1. Moreover, we found that PTPRD knockdown altered cell morphology and migration in PASMCs via modulating focal adhesion and cell cytoskeleton. We have demonstrated that the increase in cell migration is mediated by the PDGFRB/PLCγ1 pathway. Furthermore, under hypoxic condition, we observed significant pulmonary arterial remodeling and exacerbation of pulmonary hypertension in heterozygous PTPRD knock-out rats compared with the wild-type group. We also demonstrated that HET group treated with chronic hypoxia have higher expression and activity of PLCγ1 in the pulmonary arteries compared with wild-type group.

CONCLUSION

We propose that PTPRD likely plays an important role in the process of pulmonary vascular remodeling and development of pulmonary hypertension in vivo .

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.

Schistosomiasis-associated pulmonary arterial hypertension: survival in endemic area in Brazil

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The PHC registry equation accurately predicted survival in Sch-PAH patients.

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Sch-PAH survival cannot be safely predicted using only validated clinical variables only.

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Survival studies in endemic regions of Schistosomiasis are needed to establish the real prognosis of Sch-PAH in the world.

Background

The survival of schistosomiasis-associated pulmonary arterial hypertension (Sch-PAH) patients in endemic areas is unknown, but can be estimated using predictive equations.

Methods

We retrospectively analyzed all consecutive patients diagnosed with Sch-PAH referred to the Pronto SocorroCardiologico de Pernambuco between 2004 and 2010 using specific therapy and measured laboratory, diagnostic imaging, and baseline hemodynamic parameters. Observed and predicted survivals according to the National Institutes of Health (NIH) and Pulmonary Hypertension Connection (PHC) registry equations were compared by the Kaplan–Meier method, log-rank test and Cox proportional hazards model.

Results

Sixty-eight patients (47 [69.1%] women) observed for a mean of 3.1 years (range, 7–72 months), median survival was 74 months, and 42 (61.7%) survived. The sex and age distributions were similar for functional class I/II and III/IV patients. Hemodynamic abnormalities were severe: mean right atrial pressure, 12.6 ± 6.2 mmHg; mean pulmonary artery pressure, 60.3 ± 13.69 mmHg; pulmonary vascular resistance, 14.62 ± 7.04 Wood units; and cardiac index, 2.3 ± 0.8 L/min/m². The usual idiopathic PAH predictors were not prognostic in Sch-PAH patients. The 1-, 3- and 5-year survival rates were 92.1%, 75.2%, and 50.8%, respectively, and those estimatedby the NIH and PHC registry equations were 68%, 45% and 32% (p = 0.001), and 93%, 79% and 68% (p = 0.340), respectively.

Conclusions

Sch-PAH patients in endemic areas have severe hemodynamic profiles and reduced long-term survivaldespite treatment. The PHC registry equation may be a useful tool to estimate survival in Sch-PAH.

Nitrated fatty acids in cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of death and accounts for one third of disease-related mortality worldwide. Dysregulated redox mechanisms, in particular the formation of reactive oxygen species (ROS) play a pivotal pathogenetic role in CVD. Nitro-fatty acids (NO2-FAs) are electrophilic molecules which have a NO2-group bound to one of their olefinic carbons. They are endogenously formed by the reaction of reactive nitrogen species with unsaturated fatty acids. Basal levels of NO2-FAs are in the low nanomolar range and higher concentrations can be encountered under acidic (stomach) and inflammatory (e.g. ischemia/reperfusion) conditions. Dietary intake of polyunsaturated fatty acids in combination with nitrites raises circulating NO2-FAs to a clinically relevant level in mice. NO2-FAs undergo reversible covalent binding to cysteine residues and by virtue of these posttranslational protein modifications act as potent anti-inflammatory signaling mediators via modulation of various critical pathways like nuclear factor E2-related factor 2 (Nrf2)- and peroxisome proliferator-activated receptor γ (PPARγ) activation, nuclear factor-kappa B (NF-κB) inhibition and hem oxygenase-1 (HO-1)- and heat shock protein (HSP) induction. In this review article, we summarize recent findings about the effects and underlying molecular mechanisms of NO2-FAs from a variety of pre-clinical cardiovascular disease models. The described findings suggest the potential of NO2-FAs to emerge as therapeutic agents with a broad range of potential clinical applications for CVD.

Update on pulmonary arterial hypertension research: proceedings from a meeting of experts

BACKGROUND

While pulmonary arterial hypertension (PAH) remains a progressive, symptomatic condition characterized by increased pulmonary vascular resistance, ultimately leading to right heart failure, great strides have been made in its understanding and treatment over the past two decades.

REVIEW

Continued research in pre-clinical, clinical, and health economic areas of research, in addition to registry analyses and technology advances, is critical for understanding the pathophysiology of the disease and devising the best ways to monitor and manage patients. On December 3, 2016, the latest pre-clinical, clinical, health economic outcome, and registry data on PAH was presented in a symposium sponsored by Actelion. This paper reviews the published research and insight into upcoming research that was presented at this interactive meeting.

The transient receptor potential vanilloid-3 regulates hypoxia-mediated pulmonary artery smooth muscle cells proliferation via PI3K/AKT signaling pathway

OBJECTVES

Transient receptor potential vanilloid 3 (TRPV3) is a member of the TRP channels family of Ca²⁺ -permeant cation channels. In this study, we aim to investigate the role of TRPV3 in pulmonary vascular remodeling and PASMCs proliferation under hypoxia.

MATERIALS AND METHODS

The expression of TRPV3 was evaluated in patients with pulmonary arterial hypertension (PAH) and hypoxic rats, using hematoxylin and eosin (H&E) and immunohistochemistry. In vitro, MTT assay, flow cytometry, Western blotting and immunofluorescence were performed to investigate the effects of TRPV3 on proliferation of PASMCs.

RESULTS

We found that, in vivo, the expression of TRPV3 was increased in patients with PAH and hypoxic rats. Right ventricular hypertrophy measurements and pulmonary pathomorphology data show that the ratio of the heart weight/tibia length (HW/TL), the right ventricle/left ventricle plus septum (RV/LV+S) and the medial width of the pulmonary artery were increased in chronic hypoxic rats. Moreover, the expression of proliferating cell nuclear antigen (PCNA), Cyclin D, Cyclin E and Cyclin A, phospho-CaMKII (p-CaMKII) were induced by hypoxia. In vitro, we revealed that hypoxia promoted PASMCs viability, increased the expression of PCNA, Cyclin D, Cyclin E, Cyclin A p-CaMKII, made more cells from G₀ /G₁ phase to G₂ /M + S phase, enhanced the microtubule formation, and increased [Ca²⁺ ]_i , which could be suppressed by Ruthenium Red, an inhibitor of TRPV3, and TRPV3 silencing has similar effects. Furthermore, the up-regulated expression of PCNA, Cyclin D, Cyclin E and Cyclin A, the increased number of cells in G₂ /M and S phase, and the enhanced activation and expression of PI3K and AKT proteins induced by hypoxia and in presence of carvacrol (an agonist of TRPV3), was significantly attenuated by incubation of LY 294002, a specific inhibitor for PI3K/AKT.

CONCLUSIONS

These findings suggest that TRPV3 is involved in hypoxia-induced pulmonary vascular remodeling and promotes proliferation of PASMCs and the effect is, at least in part, mediated via the PI3K/AKT pathway.

VISION LOSS IN A PATIENT WITH PRIMARY PULMONARY HYPERTENSION AND LONG-TERM USE OF SILDENAFIL

PURPOSE

To describe a case of bilateral, asymmetrical outer macular atrophy in a patient with pulmonary hypertension treated with long-term sildenafil (Revatio).

METHODS

Case report with fundus photography, spectral domain optical coherence tomography, fundus autofluorescence, and fluorescein angiography imaging.

RESULTS

A 32-year-old African American woman with a history of primary pulmonary hypertension and 5-year history of oral sildenafil (Revatio) use presented with decreasing central vision in her left eye. She reported a decline in central vision in the left eye that started 1 month after treatment initiation and progressed until discontinuation 5 years later. Visual acuity was 20/20 in the right eye and 20/100 in the left eye. Fundus photography revealed retinal pigment epithelial mottling and atrophy in the right eye and parafoveal retinal pigment epithelial mottling and atrophy in a ring-like configuration of the left eye. Optical coherence tomography demonstrated outer retinal irregularity in the right eye and disrupted outer retina involving the external limiting membrane, inner segment/outer segment junction, and the retinal pigment epithelium in the left eye; no choroidal thickening was observed. Fundus autofluorescence showed mild hypoautofluorescence in the foveal center with an irregular autofluorescence pattern in the parafovea of the left eye. Fluorescein angiography revealed capillary dropout with pinpoint hyperfluorescence and leakage in the far periphery bilaterally. A window defect was also observed in the foveal center of the left eye.

CONCLUSION

Sildenafil and other PDE5 inhibitors have been associated with several ocular side effects. However, this is the first report in the literature of outer macular atrophy in a patient with pulmonary hypertension and long-term use of oral sildenafil. All patients with long-term use of sildenafil should be educated on the risk of potential visual adverse effects.

Managing the Patient With Pulmonary Arterial Hypertension and Methamphetamine Use: A Practical Perspective for the Clinician

Pulmonary arterial hypertension (PAH) is a serious, chronic, progressive cardiopulmonary disease. PAH is associated with several concomitant conditions, as well as drugs and toxins.12 Methamphetamine abuse is likely associated with the development of PAH.3 Methamphetamine abuse is epidemic in the United States and abroad, with rates of new users escalating since 2012. There are over 100,000 new users annually as young as 12 years old. Treating a patient with a history of methamphetamine abuse poses many challenges for a clinician, including nonadherence, therapeutic treatment selection, complex psychosocial issues, and relapse or continued drug abuse. Patients with methamphetamine-associated PAH (Meth-APAH) have higher mortality rates when compared to idiopathic PAH.3 Having a better understanding of the complexities of addiction and working with a multidisciplinary team that includes a social worker to provide care and counseling to these patients can improve their trajectory. In this article, we will offer insight and background into methamphetamine abuse and addiction, as well as discuss a practical approach for clinicians in treating a patient with Meth-APAH, based on the literature, as well as our personal experiences at University of California, San Francisco Medical Center.

Syncope and the risk of sudden cardiac death: Evaluation, management, and prevention

Syncope is a clinical syndrome defined as a relatively brief self-limited transient loss of consciousness (TLOC) caused by a period of inadequate cerebral nutrient flow. Most often the trigger is an abrupt drop of systemic blood pressure. True syncope must be distinguished from other common non-syncope conditions in which real or apparent TLOC may occur such as seizures, concussions, or accidental falls. The causes of syncope are diverse, but in most instances, are relatively benign (e.g., reflex and orthostatic faints) with the main risks being accidents and/or injury. However, in some instances, syncope may be due to more worrisome conditions (particularly those associated with cardiac structural disease or channelopathies); in such circumstances, syncope may be an indicator of increased morbidity and mortality risk, including sudden cardiac death (SCD). Establishing an accurate basis for the etiology of syncope is crucial in order to initiate effective therapy. In this review, we focus primarily on the causes of syncope that are associated with increased SCD risk (i.e., sudden arrhythmic cardiac death), and the management of these patients. In addition, we discuss the limitations of our understanding of SCD in relation to syncope, and propose future studies that may ultimately address how to improve outcomes of syncope patients and reduce SCD risk.

The prognostic significance of tricuspid valve regurgitation in pulmonary arterial hypertension

INTRODUCTION

Tricuspid valve regurgitation (TR) is a frequent finding in patients with pulmonary arterial hypertension (PAH). However, its prognostic significance and relation to PAH, while suspected, are poorly understood. We assessed 727 consecutive patients with newly diagnosed PAH who underwent transthoracic echocardiographic evaluation of tricuspid valve function.

OBJECTIVES

The study objective was to determine the association of TR presence and severity with patient characteristics, pulmonary artery hemodynamics and outcome.

METHODS

Consecutive patients with newly diagnosed PAH (N = 727 with group 1 pulmonary hypertension) underwent transthoracic echocardiographic evaluation of tricuspid valve function at diagnosis. The primary study end point was all-cause mortality or lung transplantation.

RESULTS

In this population, 702 patients (96.5%) had TR; in 165 patients (23%), TR was severe. Compared with those with no or mild TR by echocardiography criteria, patients with severe TR had shorter mean (SD) 6-minute walk distances (285 [125] m vs 360 [121] m; P = .02) and higher levels of B-type natriuretic peptide (695 [672] pg/dL vs 328 [300] pg/dL; P < .05). Severe TR was associated with greater right atrial dilatation (91% vs 47%; P = .004) and right ventricular (RV) dilatation (92% vs 51%; P = .008), greater right atrial pressure (mean [SD] 15 [7] mm Hg vs 10 [6] mm Hg; P < .001) and lower cardiac index (mean [SD], 2.2 [0.7] L/min/m2 vs 2.8 [0.9] L/min/m2; P < .001). Severe TR was strongly predictive of greater 5-year mortality risk after adjustment for age, sex, functional class, 6-minute walk distance, diffusing capacity, RV size and pulmonary vascular resistance index (adjusted hazard ratio, 1.83; 95% CI, 1.38-2.41; P < .001).

CONCLUSIONS

Severe TR was a significant predictor of long-term mortality rate in PAH, and TR severity correlated with PAH severity.

Pediatric Perioperative Pulmonary Arterial Hypertension: A Case-Based Primer

The perioperative period is an extremely tenuous time for the pediatric patient with pulmonary arterial hypertension. This article will discuss a multidisciplinary approach to preoperative planning, the importance of early identification of pulmonary hypertensive crises, and practical strategies for postoperative management for this unique group of children.

Integrated Transitions of Care for Patients With Rare Pulmonary Diseases

PURPOSE/OBJECTIVES

Many continuing education (CE) resources are available to support case management professionals in developing competencies in transitions of care (TOC) that apply generally across disease areas. However, CE programs and tools are lacking for advanced TOC competencies in specific disease areas. This article describes 2 projects in which leading TOC, case management, and CE organizations collaborated to develop CE-accredited interdisciplinary pathways for promoting safe and effective TOC for patients with rare pulmonary diseases, including pulmonary arterial hypertension (PAH) and idiopathic pulmonary fibrosis (IPF).

PRIMARY PRACTICE SETTING(S)

The interdisciplinary pathways apply to PAH and IPF case management practice and TOC across settings that include community-based primary care and specialty care, PAH or IPF centers of expertise, acute care and post-acute settings, long-term care, rehabilitation and skilled nursing facilities, and patients' homes.

FINDINGS/CONCLUSIONS

Both PAH and IPF are chronic, progressive respiratory diseases that are associated with severe morbidity and mortality, along with high health care costs. Because they are relatively rare diseases with nonspecific symptoms and many comorbidities, PAH and IPF are difficult to diagnose. Early diagnosis, referral to centers of expertise, and aggressive treatment initiation are essential for slowing disease progression and maintaining quality of life and function. Both the rarity and complexity of PAH and IPF pose unique challenges to ensuring effective and safe TOC. Expert consensus and evidence-based approaches to meeting these challenges, and thereby improving PAH and IPF patient outcomes, are presented in the 2 interdisciplinary TOC pathways that are described in this article.

IMPLICATIONS FOR CASE MANAGEMENT PRACTICE

In coordinating care for patients with complex pulmonary diseases such as PAH and IPF, case managers across practice settings can play key roles in improving workflow processes and communication, transition planning, coordinating TOC with centers of expertise, coordinating care and TOC for patients with comorbidities, providing patient and caregiver education, promoting engagement between patients and the team, advancing the care plan, and improving ongoing adherence to treatment in order to maximize the patient's pulmonary function. Details regarding these interprofessional roles and responsibilities are provided in the full interdisciplinary TOC pathways for PAH and IPF.

Chemical and biological assessment of metal organic frameworks (MOFs) in pulmonary cells and in an acute in vivo model: relevance to pulmonary arterial hypertension therapy

Pulmonary arterial hypertension (PAH) is a progressive and debilitating condition. Despite promoting vasodilation, current drugs have a therapeutic window within which they are limited by systemic side effects. Nanomedicine uses nanoparticles to improve drug delivery and/or reduce side effects. We hypothesize that this approach could be used to deliver PAH drugs avoiding the systemic circulation. Here we report the use of iron metal organic framework (MOF) MIL-89 and PEGylated MIL-89 (MIL-89 PEG) as suitable carriers for PAH drugs. We assessed their effects on viability and inflammatory responses in a wide range of lung cells including endothelial cells grown from blood of donors with/without PAH. Both MOFs conformed to the predicted structures with MIL-89 PEG being more stable at room temperature. At concentrations up to 10 or 30 µg/mL, toxicity was only seen in pulmonary artery smooth muscle cells where both MOFs reduced cell viability and CXCL8 release. In endothelial cells from both control donors and PAH patients, both preparations inhibited the release of CXCL8 and endothelin-1 and in macrophages inhibited inducible nitric oxide synthase activity. Finally, MIL-89 was well-tolerated and accumulated in the rat lungs when given in vivo. Thus, the prototypes MIL-89 and MIL-89 PEG with core capacity suitable to accommodate PAH drugs are relatively non-toxic and may have the added advantage of being anti-inflammatory and reducing the release of endothelin-1. These data are consistent with the idea that these materials may not only be useful as drug carriers in PAH but also offer some therapeutic benefit in their own right.

Non-invasive monitoring of pulmonary artery pressure at the bedside

Current solutions for the monitoring of pulmonary artery pressure (PAP) in patients suffering from pulmonary hypertension are limited to invasive means. Non-invasive alternatives, such as Doppler echocardiography, are incompatible with continuous monitoring due to their dependency on qualified personnel to perform the measurements. In the present study, a novel non-invasive and unsupervised approach based on the use of electrical impedance tomography (EIT) is presented. The approach was evaluated in three healthy subjects undergoing hypoxia-induced variations in PAP. A timing parameter - physiologically linked to the PAP via the so-called pulse wave velocity principle - was automatically extracted from the EIT data. Reference systolic PAP estimates were obtained by echocardiography. Strong correlation scores (r e [0.844, 0.990]) were found between the EIT-derived parameter and the reference PAP, thereby suggesting the validity of the proposed approach. If confirmed in larger datasets, these findings could open the way for a new branch of fully non-invasive hemodynamic monitors for patients with pulmonary hypertension.

Usefulness of High-Density Lipoprotein Cholesterol to Predict Survival in Pulmonary Arterial Hypertension

It has been suggested that lipoprotein abnormalities may contribute to the pulmonary arteriolar dysfunction observed in pulmonary arterial hypertension (PAH). High-density lipoprotein cholesterol (HDL) has vasodilatory, anti-inflammatory, and endothelial protective properties. We hypothesized that a higher serum HDL level may be advantageous for survival in PAH and that the serum HDL level at diagnosis would be an independent predictor of survival in PAH and be additive to previously validated predictors of survival. This study included all patients with PAH seen at the Mayo Clinic Pulmonary Hypertension Clinic from January 1, 1995, to December 31, 2009, who had a baseline HDL measurement. Mortality was analyzed over 5 years using the Kaplan-Meier method. Univariate and multivariable Cox proportional hazards ratios were calculated to evaluate the relation between baseline HDL level and survival. HDL levels were available for 227 patients. Higher HDL levels were associated with significantly lower mortality. Patients with an HDL >54 mg/dl at diagnosis had a 5-year survival of 59%. By comparison those with an HDL <34 mg/dl had a 5-year survival of 30%. On multivariate analysis, higher HDL was associated with an age-adjusted risk ratio for death of 0.78 (CI 0.67 to 0.91; p <0.01) per 10 mg/dl increase. In conclusion, HDL was an independent predictor of survival in PAH.

Impact of age on pulmonary artery systolic pressures at rest and with exercise

AIM

It is not well known if advancing age influences normal rest or exercise pulmonary artery pressures. The purpose of the study was to evaluate the association of increasing age with measurements of pulmonary artery systolic pressure at rest and with exercise.

SUBJECTS AND METHODS

A total of 467 adults without cardiopulmonary disease and normal exercise capacity (age range: 18-85 years) underwent symptom-limited treadmill exercise testing with Doppler measurement of rest and exercise pulmonary artery systolic pressure.

RESULTS

There was a progressive increase in rest and exercise pulmonary artery pressures with increasing age. Pulmonary artery systolic pressures at rest and with exercise were 25±5mmHg and 33±9mmHg, respectively, in those <40 years, and 30±5mmHg and 41±12mmHg, respectively, in those ≥70 years. While elevated left-sided cardiac filling pressures were excluded by protocol design, markers of arterial stiffness associated with the age-dependent effects on pulmonary pressures.

CONCLUSION

These data demonstrate that in echocardiographically normal adults, pulmonary artery systolic pressure increases with advancing age. This increase is seen at rest and with exercise. These increases in pulmonary pressure occur in association with decreasing transpulmonary flow and increases in systemic pulse pressure, suggesting that age-associated blood vessel stiffening may contribute to these differences in pulmonary artery systolic pressure.

New Therapeutic Paradigms and Guidelines in the Management of Pulmonary Arterial Hypertension

BACKGROUND

Recent and ongoing developments in the diagnosis, treatment, and management of pulmonary arterial hypertension (PAH) provide deeper insights into pathogenic mechanisms. Approvals of new pharmacotherapies that improve function and reduce morbidity and mortality risks; advances in clinical trial methods, including long-term, event-driven studies with clinically relevant and patient-centered endpoints; and trial results support a new therapeutic management strategy. This new paradigm involves initial treatment with combined therapies that act through different disease pathways. In addition, 2 new sets of clinical practice guidelines for PAH have been published since June 2014. Despite these advances, major gaps have been documented in the diagnosis, treatment, and management of patients with PAH.

OBJECTIVE

To present current knowledge and evidence on PAH to support managed care professionals and providers in achieving accurate differential diagnosis, promptly referring patients to specialists as necessary, and ensuring that patients receive appropriate, guideline-directed therapies.

SUMMARY

Major gaps in the quality of care provided to patients with PAH include oversights in clinicians' recognition of symptoms, delays in diagnosis, and misdiagnosis ensuing from incomplete evaluations, delays in referral of patients to centers of expertise and initiation of therapy, and inappropriate treatment regimens. To address deficiencies in PAH diagnosis, new practice guidelines emphasize the essential role of right heart catheterization in characterizing and confirming the disease, as well as referral to expert pulmonary hypertension centers to ensure appropriate evaluation and treatment. Updated disease and functional classifications of PAH, along with new research findings on prognostic factors and effects of comorbid conditions, offer key support for making effective therapy and management decisions for patients with PAH at different risk levels and stages of the disease. Since 2013, the U.S. Food and Drug Administration has approved new PAH therapies in the classes of endothelin receptor antagonists, guanylate cyclase stimulators, prostacyclin analogues, and prostacyclin receptor agonists. As demonstrated through phase 3 clinical trials, these generally well-tolerated therapies delay disease progression, improve hemodynamic and functional status, and decrease numbers of hospitalizations. Moreover, 2 sets of recently published guidelines-developed by the American College of Chest Physicians and the European Society of Cardiology/European Respiratory Society-provide evidence-based and expert consensus recommendations for achieving PAH treatment goals. The most recent guidelines include a recommendation for upfront combination therapy for patients with moderate disease, which is supported by new comparative clinical trial evidence. As addressed in this article, these advances in the field of PAH have important implications for managed care and clinical practice, including considerations of cost-benefit outcomes associated with different management strategies.

Physicians' and patients' expectations of therapies for pulmonary arterial hypertension: where do they meet?

In recent years, many new, effective therapies for pulmonary arterial hypertension (PAH) have become available and are widely used, yet the long-term prognosis for patients with PAH remains poor. In the absence of a cure, physicians' expectations of PAH-specific therapies are to: 1) improve patients' symptoms and functional capacity; 2) slow disease progression; and 3) improve survival. However, patients with PAH may prioritise other more tangible needs, such as improvements in their ability to carry out their daily tasks and increase their quality of life. Patients with PAH have also called out for social and emotional support from their physicians, caregivers, families and patient associations. Therefore, it is necessary that clinical trials of PAH-specific treatments include end-points that are meaningful to both patients and physicians, and that a multidisciplinary approach to the management of patients with PAH takes into consideration the broader aspects of patients' and caregivers' needs and wishes beyond simple physiological measurements.

Survival in an incident cohort of patients with pulmonary arterial hypertension in Denmark

We aimed to characterize and estimate survival rates in patients diagnosed with pulmonary arterial hypertension (PAH) in western Denmark in the modern management era. All incident cases of PAH were consecutively enrolled in our single-center prospective cohort study between January 2000 and March 2012. A total of 134 patients fulfilling the inclusion criteria were followed up from first diagnostic right heart catheterization to either death or the end of the study. Kaplan-Meier survival analysis was used to estimate 1-, 3-, and 5-year survival rates with 95% confidence intervals (CIs). Survival in the total cohort was 86.4% (95% CI, 79.3%-91.2%) after 1 year, 72.9% (95% CI, 64.1%-79.9%) after 3 years, and 65.4% (95% CI, 55.8%-73.4%) after 5 years. Significantly better survival was seen in the group of patients with PAH associated with congenital heart disease than in the group of patients with idiopathic PAH, heritable PAH, connective tissue disease, HIV infection, and portal hypertension. In conclusion, survival rates in the Danish PAH population were similar to or slightly better than survival rates estimated in other modern registries. However, PAH remains a fatal disease, despite modern targeted therapies.

Support Experienced by Patients Living with Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension

BACKGROUND

As pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are debilitating and fatal diseases it is essential to increase the understanding of patients' experience of support. The aim was to describe patients' experiences of support while living with PAH or CTEPH.

METHODS

Seventeen patients (13 women and four men) aged 28-73 years were strategically selected from a regional PAH centre and individually interviewed. The answers were analysed using qualitative content analysis.

RESULTS

Three categories that describe patients' experiences of support emerged: Support linked to the healthcare; support linked to the private sphere; and support linked to persons outside the private sphere.

CONCLUSION

Healthcare practitioners must work more in collaboration to detect patients' need for support and to develop the patient's own skills to manage daily life. The PAH teams should tailor interventions to provide emotional, informational and instrumental support and guidance to patients and their families.

Fasudil and SOD packaged in peptide-studded-liposomes: Properties, pharmacokinetics and ex-vivo targeting to isolated perfused rat lungs

The present study investigated the feasibility of encapsulating two drugs, fasudil and superoxide dismutase (SOD), into liposomes for targeted and inhalational delivery to the pulmonary vasculature to treat pulmonary arterial hypertension (PAH). Nanosized liposomes were prepared by a thin-film formation and extrusion method, and the drugs were encapsulated by a modified freeze-thaw technique. The peptide CARSKNKDC (CAR), a pulmonary-specific targeting sequence, was conjugated on the surface of liposomes. Formulations were optimized for various physicochemical properties, tested for their ex-vivo and in-vivo drug absorption after intratracheal administration, and evaluated for short-term safety in healthy rats. The homogenous nanosized liposomes contained both SOD (~55% entrapment) and fasudil (~40% entrapment), and were stable at 4°C and after nebulization. Liposomes released the drugs in a controlled-release fashion. Compared with plain liposomes, CAR-liposomes increased the uptake by pulmonary endothelial and smooth muscle cells by ~2-fold. CAR-liposomes extended the biological half-lives of SOD and fasudil by ~3-fold. Ex-vivo studies demonstrated that CAR-liposomes were better retained in the lungs than plain liposomes. Bronchoalveolar lavage studies indicated the safety of peptide-equipped liposomes as pulmonary delivery carriers. Overall, this study demonstrates that CAR-liposomes may be used as inhalational carriers for SOD plus fasudil-based combination therapy for PAH.

Hemodynamic changes of the middle hepatic vein in patients with pulmonary hypertension using echocardiography

The aim of this study was to analyze the changes of the middle hepatic vein (MHV) spectra in patients with pulmonary hypertension (PH) caused by congenital heart disease (CHD) and determine the proper parameters of MHV to predict PH. Eighty patients with CHD were included, whose pulmonary artery pressure was measured via right heart catheterization, and the MHV spectra were detected via echocardiography. The peak value of velocity (V) and velocity time integral (VTI) of the waves, including S wave, D wave and A wave, were measured at the end of inspiration. The values of the MHV parameters that were predictive of PH were evaluated and their cut-off points were determined. Compared with the control group, V of S wave (S), VTI of S wave (SVTI), V of D wave (D), VTI of D wave (DVTI) decreased and V of A wave (A), VTI of A wave (AVTI), A/S, AVTI/SVTI, A/(S+D), AVTI/ (SVTI+DVTI) increased in the PH group. These differences were statistically significant (P<0.05). A correlation analysis determined that the ratios of A/S, A/(S+D), AVTI/(SVTI+DVTI) were positively correlated with pulmonary artery mean pressure (r=0.529,0.575,0.438,P<0.001). An ROC curve analysis determined that the diagnostic effect of A/(S+D) was superior to the other two parameters. On the ROC curve, when the ratio of A/(S+D) was 0.30, the sensitivity was 85.37% and specificity was 75.00% for predicting PH. The spectral parameters of MHV, including the ratios of A/S, A/(S+D) and AVTI/(SVTI+DVTI), increased with increasing pulmonary pressure in CHD patients. When the ratio of A/(S+D) was 0.30 in MHV spectra, it had sufficient sensitivity and specificity for diagnosing PH, and this method could be used as a new non-invasive complementary echocardiographic parameter for predicting PH.

The economic burden of pulmonary arterial hypertension (PAH) in the US on payers and patients

BACKGROUND

Pulmonary arterial hypertension (PAH) is a rare condition that can ultimately lead to right heart failure and death. In this study we estimated the health care costs and resource utilization associated with PAH in a large US managed care health plan.

METHODS

Subjects with claims-based evidence of PAH from 1/1/2004 to 6/30/2010 (identification period) were selected. To be included in the final PAH study sample, subjects were required to have ≥2 claims with a primary PH diagnosis; ≥2 claims with a PAH related-diagnosis (connective tissue diseases, congenital heart diseases, portal hypertension); and ≥1 claim with evidence of a PAH-indicated medication. The earliest date of a claim with evidence of PAH-indicated medication during the identification period was set as the index date. Health care costs and resource utilization were compared between an annualized baseline period and a 12 month follow-up period.

RESULTS

504 PAH subjects were selected for the final study cohort. Estimated average total health care costs were approximately 16% lower in the follow-up period compared to the baseline period (follow-up costs = $98,243 [SD = 110,615] vs. baseline costs = $116,681 [SD = 368,094], p < 0.001), but substantively high in each period relative to costs reported for other chronic diseases. Pharmacy costs were significantly higher in the follow-up period vs. the baseline period, ($38,514 [SD = 34,817] vs. $6,440 [SD = 12,186], p < 0.001) but medical costs were significantly lower in the follow-up vs. baseline ($59,729 [SD = 106,683] vs. $110,241 [SD = 368,725], p < 0.001). These costs were mirrored in health-care resource utilization estimates. The average counts of ambulatory visits and inpatient stays were lower in the follow-up vs. the baseline (both p < 0.001). Results varied in exploratory analyses when less restrictive subject identification algorithms were used.

CONCLUSIONS

Subjects with evidence of PAH had substantively high health care costs. Medical costs appeared to decrease following PAH medication use, but with a concomitant increase in pharmacy costs.

Prognostic implications of serial risk score assessments in patients with pulmonary arterial hypertension: a Registry to Evaluate Early and Long-Term Pulmonary Arterial Hypertension Disease Management (REVEAL) analysis

BACKGROUND

Data from the Registry to Evaluate Early and Long-Term Pulmonary Arterial Hypertension Disease Management (REVEAL) were used previously to develop a risk score calculator to predict 1-year survival. We evaluated prognostic implications of changes in the risk score and individual risk-score parameters over 12 months.

METHODS

Patients were grouped by decreased, unchanged, or increased risk score from enrollment to 12 months. Kaplan-Meier estimates of subsequent 1-year survival were made based on change in the risk score during the initial 12 months of follow-up. Cox regression was used for multivariable analysis.

RESULTS

Of 2,529 patients in the analysis cohort, the risk score was decreased in 800, unchanged in 959, and increased in 770 at 12 months post-enrollment. Six parameters (functional class, systolic blood pressure, heart rate, 6-minute walk distance, brain natriuretic peptide levels, and pericardial effusion) each changed sufficiently over time to improve or worsen risk scores in ≥5% of patients. One-year survival estimates in the subsequent year were 93.7%, 90.3%, and 84.6% in patients with a decreased, unchanged, and increased risk score at 12 months, respectively. Change in risk score significantly predicted future survival, adjusting for risk at enrollment. Considering follow-up risk concurrently with risk at enrollment, follow-up risk was a much stronger predictor, although risk at enrollment maintained a significant effect on future survival.

CONCLUSIONS

Changes in REVEAL risk scores occur in most patients with pulmonary arterial hypertension over a 12-month period and are predictive of survival. Thus, serial risk score assessments can identify changes in disease trajectory that may warrant treatment modifications.

Pericardial effusions in pulmonary arterial hypertension: characteristics, prognosis, and role of drainage

BACKGROUND

The presence and size of a pericardial effusion in pulmonary arterial hypertension (PAH) and its association with outcome is unclear.

METHODS

In this single-center cohort study of 577 patients with group 1 PAH seen between January 1, 1995, and December 31, 2005, all patients underwent transthoracic echocardiography and were followed for ≥ 5 years. Echocardiography-guided pericardiocentesis was performed as needed.

RESULTS

Pericardial effusions on index echocardiography occurred in 150 patients (26%); 128 patients had small and 22 had moderate-sized or larger effusions. Most of the moderate or greater effusions occurred in patients who had connective tissue disease (82%). Mean right atrial pressure was 13.4 ± 4.4 mm Hg (no effusion), 15.1 ± 4.4 mm Hg (small effusion), and 17.0 ± 4.0 mm Hg (moderate or greater effusion) (P &lt; .0001). Median survival for patients with moderate or greater effusion, mild effusion, or no effusion was 11.3 months, 42.3 months, and 76.5 months, respectively. Four of the 22 patients with moderate or greater pericardial effusions eventually required echocardiography-guided pericardiocentesis because of clinical and echocardiographic evidence of hemodynamic impact. When drained, the effusions were large (858 ± 469 mL) and generally serous. All pericardiocenteses were performed cautiously under echocardiographic guidance by a highly experienced echocardiologist, with low immediate morbidity and mortality.

CONCLUSIONS

Pericardial effusions are relatively common but rarely of hemodynamic significance in patients with PAH. However, even modest degrees of pericardial fluid are associated with a significant increase in mortality and appear to reflect the presence of associated collagen vascular disease and high right atrial pressure.

Pulmonary hypertension and idiopathic pulmonary fibrosis: a dastardly duo

Pulmonary hypertension (PH) is a well-recognized complication of interstitial lung disease, including idiopathic pulmonary fibrosis (IPF). The underlying pathogenesis was initially hypothesized to be inflammatory but now is characterized as an over exuberant fibroproliferative process. The prevalence of PH in the setting of IPF has not been well described in the literature, with a reported occurrence from 32% to 85%. Diagnostically, recognizing underlying PH in the setting of IPF remains challenging because of nonspecific clinical symptoms and unrevealing ancillary testing. A high degree of clinical suspicion is paramount. The only reliable diagnostic tool for PH is right heart catheterization. The treatment of PH, in patients with IPF, is based on multiple factors, including disease severity, functional status and degree of hypoxemia. Medications currently approved to treat PH have been administered for PH in the setting of IPF, such as phosphodiesterase-5 inhibitors, nonselective endothelin receptor antagonists and prostacyclin analogues. The treatment of PH in the setting of IPF may also be difficult due to worsening ventilation-perfusion mismatch induced by selective pulmonary artery vasodilator therapy. Lung transplantation should be considered with patients refractory to pharmacological treatment. Identification of PH in IPF patients is crucial, as functional status and prognosis are greatly reduced. Given the high mortality rate and propensity for acute decompensation, IPF and PH patients should be evaluated for transplant early in their disease course.

Prostacyclin and its analogues in pulmonary artery hypertension: a meta-analysis

OBJECTIVE

Individual studies examining the effects of prostacyclin and its analogues on pulmonary artery hypertension (PAH) have reported controversial results. This study aims to evaluate the efficacy of these agents for PAH by a meta-analysis based on randomized controlled trials (RCTs).

RESEARCH DESIGN AND METHODS

We systematically searched Pubmed, MEDLINE, EMBASE, ISI Web of Science, and the Cochrane Library through April 2012. All published RCTs reporting the effects of treatment with prostacyclin or its analogues in PAH were included. Summary statistics were calculated using a random effects model.

RESULTS

A total of 14 RCTs with 1606 participants were analyzed. Overall, prostacyclin and its analogues increased 6-minute walk distance (6-MWD) (weighted mean differences [WMD]=18.78 meters, 95% confidence interval [CI]: 11.21 to 26.35; p<0.01) and improved NYHA functional class status (odds ratios [OR]=3.98, 95% CI: 1.70 to 9.34; p=0.001) compared with the control. Moreover, these agents led to statistically significant reductions in mean pulmonary artery pressure (mPAP) (WMD=-4.63 mmHg, 95% CI: -6.81 to -2.44; p<0.01) and pulmonary vascular resistance (PVR) (standardized mean difference [SMD] = -0.69, 95% CI: -0.96 to -0.43; p<0.01). Notably, there were distinct effects on these endpoints observed in pooled subgroup analyses based on agent class (all p for interaction<0.01). In addition, PAH-specific therapy appeared to have superiority over the control in reducing the incidence of all-cause death (OR=0.49, 95% CI: 0.26 to 0.94; p=0.03). However, there existed a substantial publication bias, which appeared to markedly impact the overall result of 6-MWD.

CONCLUSIONS

PAH-specific treatment with prostacyclin and its analogues significantly improved exercise capacity, cardiopulmonary hemodynamics, and lowered all-cause mortality in patients with PAH.

The potential efficacy of R8-modified paclitaxel-loaded liposomes on pulmonary arterial hypertension

PURPOSE

In this paper, a novel liposomal formulation of paclitaxel modified with octaarginine (R8) was fabricated and the therapeutic efficacy of it on pulmonary arterial hypertension was evaluated.

METHODS

Octaarginine-modified stealth liposomes loaded with PTX (R8-PTX-LIP) were prepared and characterized. Vector cytoxicity and anti-proliferation ability of different formulations on primary cultured VSMCs were determined with MTT assay. The uptake capacity of VSMCs on different formulations were evaluated by flow cytometry, and the influences on cytoskeletons of liposomes were investigated by cytoskeleton staining with rhodamine-phalloidin. The biodistribution of liposomes were imaged by a CCD camera using a near-infrared fluorophore DiD. The therapeutic efficacy of different PTX-formulations of PAH was evaluated by hemodynamic measurement, right ventricular hypertrophic parameters and vessel diameters.

RESULTS

The cellular uptake of R8 modified liposomes (R8-LIP) was improved noticeably compared with other groups. All liposomes did not exert cytotoxicity on VSMCs in 24 h. R8-PTX-LIP exhibited the strongest inhibitory effect on the proliferation of VSMCs among all the formulations (p < 0.001). R8-PTX-LIP could reverse the phenotype transformation, and inhibit cell migration. mPAP, (RV/LV+S) and the wall thickness of small distal pulmonary arteries of rats treated with R8-PTX-LIP were significantly lower than those from other groups (p < 0.001).

CONCLUSIONS

In conclusion, the drug delivery system of R8-modified paclitaxel-loaded liposomes we established showed pronounced inhibitory effect over VSMCs proliferation and cytoskeleton formation in vitro, a stronger pulmonary delivery ability in vivo, and was effective on PAH, showing the potential for pulmonary drug delivery system for PAH treatment.

Evolving strategies for the use of spironolactone in cardiovascular disease

The evolution of strategies for the use of spironolactone and its analogue, eplerenone, has, over the years, encompassed favourable modification of the natural history of symptomatic heart failure in subjects with subnormal left ventricular ejection fraction (LVEF), and mitigation of the risk of new-onset atrial fibrillation in mildly symptomatic systolic heart failure. Given the fact that these benefits might be attributable, at least in part, to mitigation of severity of diastolic dysfunction when the latter co-exists with subnormal LVEF, what needs to be explored is the possibility of similar benefits from the use of these agents in patients such as those with hypertension, and aortic valve stenosis, in whom left ventricular dysfunction is of the predominantly diastolic subtype.

Considerations for numerical modeling of the pulmonary circulation--a review with a focus on pulmonary hypertension

Both in academic research and in clinical settings, virtual simulation of the cardiovascular system can be used to rapidly assess complex multivariable interactions between blood vessels, blood flow, and the heart. Moreover, metrics that can only be predicted with computational simulations (e.g., mechanical wall stress, oscillatory shear index, etc.) can be used to assess disease progression, for presurgical planning, and for interventional outcomes. Because the pulmonary vasculature is susceptible to a wide range of pathologies that directly impact and are affected by the hemodynamics (e.g., pulmonary hypertension), the ability to develop numerical models of pulmonary blood flow can be invaluable to the clinical scientist. Pulmonary hypertension is a devastating disease that can directly benefit from computational hemodynamics when used for diagnosis and basic research. In the present work, we provide a clinical overview of pulmonary hypertension with a focus on the hemodynamics, current treatments, and their limitations. Even with a rich history in computational modeling of the human circulation, hemodynamics in the pulmonary vasculature remains largely unexplored. Thus, we review the tasks involved in developing a computational model of pulmonary blood flow, namely vasculature reconstruction, meshing, and boundary conditions. We also address how inconsistencies between models can result in drastically different flow solutions and suggest avenues for future research opportunities. In its current state, the interpretation of this modeling technology can be subjective in a research environment and impractical for clinical practice. Therefore, considerations must be taken into account to make modeling reliable and reproducible in a laboratory setting and amenable to the vascular clinic. Finally, we discuss relevant existing models and how they have been used to gain insight into cardiopulmonary physiology and pathology.

Impaired left ventricular mechanics in pulmonary arterial hypertension: identification of a cohort at high risk

BACKGROUND

Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling and right heart failure. The right (RV) and left ventricles (LV) do not function in isolation, sharing a common pericardial sac and interventricular septum. We sought to define the clinical and prognostic significance of ventricular interdependence in PAH and its association with LV filling patterns through speckle-tracking strain echocardiography.

METHODS AND RESULTS

Echocardiography was performed in 71 adults with a new diagnosis of PAH. To analyze LV and RV function separately, we measured peak systolic longitudinal and circumferential strain of the LV and RV. Survival was assessed >2 years. Patients had dilated right-sided chambers (right atrial volume index, 44 ± 19 mL/m(2); RV end-diastolic area, 34 ± 9 cm(2)), and reduced RV function (RV fractional area change, 28 ± 12%). Speckle-tracking echocardiography revealed significant reductions in RV free wall peak systolic strain (-15 ± 3%). Despite normal LV size and normal conventional measures of LV systolic function (end-diastolic dimension, 42 ± 6 mm; ejection fraction, 65 ± 8%; cardiac index, 2.6 ± 0.8 L/min per m(2)), patients had reduced LV free wall systolic strain (-15 ± 3%). Decreased LV free wall systolic strain was associated with a delayed relaxation mitral inflow Doppler pattern, P=0.0002. During 2-year follow-up, 19 patients (27%) died. LV strain was associated with increased mortality (unadjusted hazard ratio, 2.40 per 5% decrease in LV free wall strain, 1.22-4.68), which remained significant when adjusted for age, sex, World Health Organization functional class, and PAH pathogenesis (hazard ratio, 3.11, 1.38-7.20).

CONCLUSIONS

The pressure loading in PAH results in geometric alterations and functional decline of the RV, with marked reduction in RV systolic strain. Despite preservation of LV ejection fraction, LV systolic strain was also reduced and associated with early mortality, highlighting the significance of ventricular interdependence in PAH.

Symptom burden, quality of life, and attitudes toward palliative care in patients with pulmonary arterial hypertension: results from a cross-sectional patient survey

BACKGROUND

Pulmonary arterial hypertension (PAH) is a complex disease with variable clinical manifestations; nevertheless, morbidity and mortality associated with PAH are considerable. This study examined quality of life (QOL) in PAH patients and assessed use of palliative care (PC) for addressing QOL issues and what barriers might exist regarding early PC implementation for patients with PAH.

METHODS

An Internet-based survey was distributed to Pulmonary Hypertension Association patient-related listservs. Symptom burden and QOL were assessed using Linear Analog Self Assessment (LASA) QOL items and the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR).

RESULTS

Of 774 eligible patients with active e-mail addresses, 315 returned surveys (41% overall response), and 276 (88%) contained analyzable responses. Responders (mean age, 48.9 years ± 16.0) were predominantly white (85%), female (86%), and with idiopathic PAH (42%). Profound deficiency in overall QOL (40%), fatigue (57%), physical well-being (56%), social activity (49%), emotional well-being (49%), and pain (38%) were reported. Most patients believed their PAH physician had excellent understanding of PAH progression/plan of care (92%), but less were satisfied with care regarding QOL management (77%). Few patients considered PC (8%), or had pain management (4%) or PC involved (1%). Most common reasons were beliefs that patients were doing well/not sick (63%) or that PC had not been suggested (22%).

CONCLUSIONS

PAH may result in symptoms or QOL impairment persisting despite optimal PAH therapy. However, PC awareness or use by PAH patients and providers is low. Opportunities may exist to integrate PC into care for PAH patients.