Diagnosis and assessment of pulmonary arterial hypertension

Pulmonary Arterial Hypertension

This article provides an overview of pulmonary arterial hypertension (PAH), beginning with the initial pathologic recognition of pulmonary hypertension more than 100 years ago and progressing to the current diagnostic categorization of PAH. It reviews the epidemiology, pathophysiology, genetics, and modern treatment of PAH. The article discusses several important recent studies that have highlighted the importance of new management strategies, including serial risk assessment and combination pharmacotherapy.

The Right Heart International Network (RIGHT-NET): Rationale, Objectives, Methodology, and Clinical Implications

The Right Heart International Network is a multicenter international study aiming to prospectively collect exercise Doppler echocardiography tests of the right heart pulmonary circulation unit (RHPCU) in large cohorts of healthy subjects, elite athletes, and individuals at risk of or with overt pulmonary hypertension. It is going to provide standardization of exercise stress echocardiography of RHPCU and explore the full physiopathologic response.

Relative Importance of Baseline and Longitudinal Evaluation in the Follow-Up of Vasodilator Therapy in Pulmonary Arterial Hypertension

OBJECTIVES

The aim of this study was to evaluate the relative value of baseline and follow-up echocardiographic assessment of pulmonary artery systolic pressure (PASP) and right ventricular (RV) function in assessing response to vasodilator therapy in pulmonary arterial hypertension (PAH).

BACKGROUND

Routine follow-up of PASP and RV function is widely obtained in patients undergoing treatment for PAH, but the value of this reassessment is uncertain.

METHODS

Of 162 prospectively recruited patients with PAH, 96 were included in this analysis of patients with ≥3 sequential echocardiographic studies. PASP and RV function (including right ventricular free wall strain [RVFWS]) were measured at baseline and on follow-up 2-dimensional echocardiography. Univariate and multivariate Cox regression with nested models was used to determine incremental and independent predictors of all-cause mortality.

RESULTS

Changes between visits were minimal for all parameters (RVFWS, p = 0.46; RV end diastolic area, p = 0.48; tricuspid annular plane systolic excursion, p = 0.32; PASP, p = 0.66; right atrial area, p = 0.39; and inferior vena cava, p = 0.25). Over 3 years of follow-up, 29 patients died. Baseline RVFWS was an independent predictor of outcome (hazard ratio [HR]: 0.90; 95% confidence interval [CI]: 0.83 to 0.97; p = 0.007), incremental to PASP and other clinical covariates (C statistic = 0.74, p = 0.001). Those who died showed no differences in RVFWS (p = 0.50), PASP (p = 0.90), and tricuspid annular plane systolic excursion (p = 0.83) between visits. When baseline measures and follow-up time were accounted for, mean changes in RVFWS (HR: 0.78; 95% CI: 0.63 to 0.96; p = 0.002), right atrial area (HR: 1.20; 95% CI: 1.07 to 1.40; p = 0.003), and inferior vena cava (HR: 66.5; 95% CI: 8.5 to 520.5; p < 0.001) over follow-up were significant in predicting outcome.

CONCLUSIONS

In PAH, baseline RV function (RVFWS) is a strong predictor of outcome, independent of PASP. Changes throughout therapy appear minimal, and only changes in RVFWS, inferior vena cava, size, and right atrial area were associated with outcome.

Real-life experience of inhaled iloprost for patients with pulmonary arterial hypertension: Insights from the Spanish REHAP registry

INTRODUCTION

REHAP is a voluntary, observational Spanish registry of patients with pulmonary arterial hypertension. We analyzed the experience (use and effectiveness) with inhaled iloprost (inh-ILO) in real-life conditions during a 3-year period.

METHODS

Patients included were those with PAH ≥14 years recruited during 1998-2016 who had received inh-ILO. Variables were collected at the beginning of treatment (0 ± 3 months) and 12 ± 3/36 ± 6 months follow-up. Effectiveness was assessed in the intent-to-treat population as changes in functional class and/or physical performance and transplant-free survival from the beginning of treatment. Stopping inh-ILO-related survival was also assessed. Subanalyses included treatment strategy (first-line therapy -monotherapy or upfront combination- or sequential therapy) and risk of clinical worsening/death.

RESULTS

Inh-ILO was the most frequently used prostanoid in Spain, rendering 267 patients eligible for analysis. Median age was 54 years; 61% were WHO FC III. Sixty (23%) patients started inh-ILO as monotherapy, 27 (10%) as upfront combination and 180 (67%) sequentially. At 3-year follow-up significant clinical improvements were observed; however, transplant-free survival rate was 54%, being poorer in patients at high risk (63% vs. 85% in low risk patients; P < 0.001) and similar in the three treatment strategies. Only 25% patients remained on inh-ILO. Three-year after stopping inh-ILO-related survival rate was 24.7%.

CONCLUSION

Data from the REHAP collected during 3 years shows that inh-ILO has low effectiveness independently of the treatment strategy used, with a 3-year survival rate of 54% despite significant clinical improvements, probably due to the use in high-risk patients. Discontinuation rate was as high as 75%.

Right Ventricular Function is Associated With Quality of Life in Patients With Systemic Lupus Erythematosus Associated Pulmonary Arterial Hypertension

BACKGROUND

Right ventricular (RV) function has been identified as an important determinant of outcome in patients with pulmonary hypertension. We aimed to investigate the relationship between echocardiographic-derived RV function and health-related quality of life (HRQOL) in patients with systemic lupus erythematosus associated pulmonary arterial hypertension (SLE-APAH), and to identify the best echocardiographic parameter for evaluating RV function in these patients.

METHODS

Sixty (60) consecutive patients with SLE-APAH (all female, mean age 33.6±8.2years) were recruited from May 2013 to November 2014. Echocardiograph, right heart catheterisation, SLE disease activity index (SLEDAI), and functional status and SF-36 generic questionnaire were assessed.

RESULTS

Echocardiograph-derived RV systolic function was significantly correlated with haemodynamics (p<0.05), with tricuspid annular plane systolic excursion (TAPSE) showing the strongest correlation with pulmonary vascular resistance (R²=0.278, p<0.001) and cardiac index (R²=0.215, p<0.001). Patients with a TAPSE<17mm had a shorter 6-minute-walk-distance (6MWD), lower mixed venous oxygen saturation, and higher plasma N-terminal pro-brain natriuretic peptide (p<0.05). Patients with TAPSE <17mm had lower physical component summary (PCS) and mental component summary (MCS) scores than those with TAPSE ≥17mm (35.5±13.2 vs. 55.0±15.5; 46.3±15.3 vs. 64.8±18.8, respectively, all p<0.05). On multiple regression analysis, a TAPSE <17mm was independently related to lower PCS (β -15.797, 95% confidence interval [CI] -24.746 to -6.848, p=0.001) and lower MCS (β -12.887, 95% CI -24.018 to -1.755, p=0.024).

CONCLUSIONS

TAPSE is a useful index for RV function assessment, and is associated with HRQOL in patients with SLE-APAH.

Pulmonary-Systemic Pressure Ratio Correlates with Morbidity in Cardiac Valve Surgery

OBJECTIVES

Pulmonary hypertension portends worse outcomes in cardiac valve surgery; however, isolated pulmonary artery pressures may not reflect patients' global cardiac function accurately. To better account for the interventricular relationship, the authors hypothesized that patients with greater pulmonary-systemic ratios (mean pulmonary arterial pressure)/(mean systemic arterial pressure) would correlate with worse outcomes after valve surgery.

DESIGN

Retrospective cohort study.

SETTING

Single academic hospital.

PARTICIPANTS

The study comprised 314 patients undergoing valve surgery with or without coronary artery bypass grafting (2004-2016) with Society of Thoracic Surgeons predicted risk scores and preoperative right heart catheterization.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The pulmonary-systemic ratio was calculated as follows: mean pulmonary arterial pressure/mean systemic arterial pressure. Patients were stratified by pulmonary-systemic ratio quartile. Logistic regression was used to assess the risk-adjusted association between pulmonary-systemic ratio or mean pulmonary arterial pressure. Median pulmonary-systemic ratio was 0.33 (Q1-Q3: 0.23-0.65); median pulmonary arterial pressure was 29 (21-30) mmHg. Patients with the highest pulmonary-systemic ratio had the highest rates of morbidity and mortality (p < 0.0001). A high pulmonary-systemic ratio was associated with longer duration in the intensive care unit (p < 0.0001) and hospital (p < 0.0001). After risk-adjustment, pulmonary-systemic ratio and pulmonary arterial pressure were independently associated with morbidity and mortality, but the pulmonary-systemic ratio (odds ratio 23.88, p = 0.008, Wald 7.1) was more strongly associated than the pulmonary arterial pressure (odds ratio 1.035, p = 0.011, Wald 6.5).

CONCLUSIONS

The pulmonary-systemic ratio is more strongly associated with risk-adjusted morbidity and mortality in valve surgery than pulmonary arterial pressure. By integrating ventricular interactions, this metric may better characterize the risk of valve surgery.

Quantitative assessment of pulmonary vascular alterations in chronic obstructive lung disease: Associations with pulmonary function test and survival in the KOLD cohort

PURPOSE

Despite the high prevalence of pulmonary vascular alterations and their substantial impact on chronic obstructive pulmonary disease (COPD), tools for the direct in vivo assessment of pulmonary vascular alterations remain limited. Thus, the purpose of this study was to automatically extract pulmonary vessels from volumetric chest CT and evaluate the associations between the derived quantitative pulmonary vessel features and clinical parameters, including survival, in COPD patients.

METHODS

This study included 344 adult COPD patients. Pulmonary vessels were automatically extracted from volumetric chest CT data. Quantitative pulmonary vessel features were obtained from various lung surface areas (LSAs), which are theoretical surface areas drawn at different depths from the pleural borders. The total number of vessels (N_total) and number of vessels with vessel area (VA) less than 5 mm² (N_<5mm) were counted as both robust values and as values per 10 cm² of LSA (N_total/LSA; N_<5mm/LSA). The average VA (VA_mean) and percentage of measured VA in the corresponding LSA (%VA) were measured. Associations between quantitative pulmonary vessel features and clinical parameters, including survival and the pulmonary function test (PFT), were evaluated.

RESULTS

The pulmonary vessels were automatically extracted with 100% technical success. Cox regression analysis showed N_total/LSA, N_<5mm/LSA, VA_mean, and %VA to be significant predictors of survival (hazard ratio (HR), 0.80, 0.75, 0.70, 0.49, respectively). Patients classified into high-risk groups by %VA_18mm (cut-off = 3.258), chosen because it demonstrated the strongest statistical influence on survival in a univariate Cox analysis, were associated with worse overall survival before (HR, 4.83; p < 0.001) and after adjustment for patient age and BMI (HR, 2.18; p = 0.014). Of the quantitative pulmonary vessel features, N_total/LSA, N_<5mm/LSA, and %VA were correlated with FEV₁, FEV₁/FVC, and DLCO in all LSAs. The strongest correlation with PFTs was noted at LSA_9mm for both N_total (FEV₁, r = 0.33; FEV₁/FVC, r = 0.51) and N_<5mm (FEV₁, r = 0.35; FEV₁/FVC, r = 0.52). For %VA, the association was most evident at LSA_18mm (FEV₁, r = 0.27; FEV₁/FVC, r = 0.47). Significant moderate to strong correlations were consistently observed between the extent of emphysema and quantitative pulmonary vessel features (r = 0.44-0.66; all p < 0.001).

CONCLUSIONS

The automated extraction of pulmonary vessels and their quantitative assessment are technically feasible. Various quantitative pulmonary vessel features demonstrated significant relationships with survival and PFT in COPD patients. Of the various quantitative features, the percentage of total VA measured at 18 mm depth from the pleural surface (%VA_18mm) and the number of small vessels counted per 10 cm² of LSA at 9 mm depth from the pleural surface (N_<5mm/LSA_9mm) had the strongest predictability for the clinical parameters.

Exome data clouds the pathogenicity of genetic variants in Pulmonary Arterial Hypertension

BACKGROUND

We aimed to provide a set of previously reported PAH-associated missense and nonsense variants, and evaluate the pathogenicity of those variants.

METHODS

The Human Gene Mutation Database, PubMed, and Google Scholar were searched for previously reported PAH-associated genes and variants. Thereafter, both exome sequencing project and exome aggregation consortium as background population searched for previously reported PAH-associated missense and nonsense variants. The pathogenicity of previously reported PAH-associated missense variants evaluated by using four in silico prediction tools.

RESULTS

In total, 14 PAH-associated genes and 180 missense and nonsense variants were gathered. The BMPR2, the most frequent reported gene, encompasses 135 of 180 missense and nonsense variants. The exome sequencing project comprised 9, and the exome aggregation consortium counted 25 of 180 PAH-associated missense and nonsense variants. The TOPBP1 and ENG genes are unlikely to be the monogenic cause of PAH pathogenesis based on allele frequency in background population and prediction analysis.

CONCLUSION

This is the first evaluation of previously reported PAH-associated missense and nonsense variants. The BMPR2 identified as the major gene out of 14 PAH-associated genes. Based on findings, the ENG and TOPBP1 gene are not likely to be the monogenic cause of PAH.

Clinical and Echocardiographic Predictors of Outcomes in Patients With Pulmonary Hypertension

In pulmonary hypertension (PH), measurement of various echocardiographic parameters that assess right heart function is recommended by current clinical guidelines. Limited data exists on the combined value of clinical and echocardiographic parameters in precapillary PH in the modern era of therapy. We examined the association of clinical and echocardiographic parameters with surrogate outcomes (6-minute walk distance) and hard outcomes (hospitalization or death) in patients with precapillary PH. A cohort of patients with an established diagnosis of precapillary PH who underwent transthoracic echocardiography at the Duke Echo Lab were prospectively enrolled from 2010 to 2014. Univariable and multivariable models were constructed to examine the relation of clinical and echocardiographic parameters with surrogate and hard outcomes. Of the 98 patients with analyzable echocardiograms with good image quality, 85 were woman, mean age was 59.4 years, and 47% had ≥World Health Organization functional class III symptoms. The mean 6-minute walk distance was 354(±132) m, and 83% were on pulmonary arterial hypertension medications. At 24 months, the cumulative incidence rate for hospitalization or death was 47%. In univariable analyses, the REVEAL (Registry to Evaluate Early and Long-term PAH Disease Management) risk score (HR 1.72 per 1 SD (2.81) increment, 95% CI 1.34, 2.22; p=<0.001), RV global longitudinal strain (RVGLS) (HR 1.54 per 1 SD (5.31) worsening, 95% CI , 2.12; p=0.008) and log-2 NT proBNP (HR 1.43 per 1-fold increase, 95% CI 1.25, 1.63; p=<0.001) were significantly associated with hospitalization or death.

Pulmonary arterial hypertension in the elderly: Clinical perspectives

Pulmonary hypertension (PH) is a rare and devastating disease characterized by progressive increases in pulmonary arterial pressure and pulmonary vascular resistance, which eventually leads to right ventric-ular failure and death. Pulmonary arterial hypertension (PAH) (World Health Organization Group I), a subset of PH, and may be idiopathic in nature or associated with other systemic conditions and is thought to most commonly effect women, the majority of whom are of childbearing age. However, PAH in the elderly population is being increasingly diagnosed creating clinical considerations that had once not been considered. Often in an elderly population the diagnosis of PAH may be delayed due to chronic comorbid conditions such as coronary artery disease or other dyspneic conditions. Though survival and clinical outcomes have improved, the elderly population continues to have disproportionately lower survival rates. High clinical suspicion of PAH warrants a complete diagnostic workup with right heart catheterization. Upon diagnosis, PAH specific therapy should be initiated with possible drug interactions in mind. Adjuvant pulmonary rehabilitation should be considered as a conservative measure with definitive results. Finally, psychosomatic aspects of the disease should also be considered in elderly populations.

Echocardiographic evolution of pulmonary hypertension in female patients with hyperthyroidism

Objective:

The objective of this study was to highlight the impact of increased cardiac output (CO) and/or pulmonary vascular resistance (PVR) on the occurrence and evolution of pulmonary hypertension (PH) in hyperthyroidism and to follow their evolution in patients under therapy.

Methods:

Our study group consisted of 142 women with hyperthyroidism of different severities and etiologies. We divided our patients into three groups: groups A (overt hyperthyroidism), B (recurrent disease), and C (subclinical forms). We performed echocardiography to determine echocardiographically estimated systolic pulmonary arterial pressure (eePAP), CO, and PVR before and at 3, 6, and 12 months after treatment with thyroid suppression therapy and beta-blockers.

Results:

In our study group we documented PH of various severities in 73 patients (51.4%). Increased CO, induced mostly by hyperthyroidism-specific tachycardia, was frequently detected in overt hyperthyroidism and also augmented PVR, as documented in 43.66% of patients with severe and recurrent forms. For all patients with PH, we emphasized a strong correlation between eePAP and PVR level (r=0.854, p<0.0001) and a moderate one with CO (r=0.437, p<0.0001) and with hyperthyroidism duration (r=0.545, p<0.0001). Under therapy, CO rapidly normalized and PVR significantly decreased in groups A and C. In group B, the reduction was modest and statistically significant.

Conclusion:

The pathophysiological mechanisms responsible for the occurrence of PH are elevated CO and PVR. While increased CO is rapidly alleviated under therapy, elevated eePAP and PVR persist in recurrent cases and are responsible for the perpetuation of PH.

Serum biomarker for diagnostic evaluation of pulmonary arterial hypertension in systemic sclerosis

Background

Systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) is one of the leading causes of death in SSc. Identification of a serum-based proteomic diagnostic biomarker for SSc-PAH would allow for rapid non-invasive screening and could positively impact patient survival. Identification and validation of novel proteins could potentially facilitate the identification of SSc-PAH, and might also point to important protein mediators in pathogenesis.

Methods

Thirteen treatment-naïve SSc-PAH patients had serum collected at time of diagnosis and were used as the discovery cohort for the protein-expression biomarker. Two proteins, Midkine and Follistatin-like 3 (FSTL3) were then validated by enzyme-linked immunosorbent assays. Midkine and FSTL3 were tested in combination to identify SSc-PAH and were validated in two independent cohorts of SSc-PAH (n = 23, n = 11).

Results

Eighty-two proteins were found to be differentially regulated in SSc-PAH sera. Two proteins (Midkine and FSTL3) were also shown to be elevated in publicly available data and their expression was evaluated in independent cohorts. In the validation cohorts, the combination of Midkine and FSTL3 had an area under the receiver operating characteristic curve (AUC) of 0.85 and 0.92 with respective corresponding measures of sensitivity of 76% and 91%, and specificity measures of 76% and 80%.

Conclusions

These findings indicate that there is a clear delineation between overall protein expression in sera from SSc patients and those with SSc-PAH. The combination of Midkine and FSTL3 can serve as an SSc-PAH biomarker and are potential drug targets for this rare disease population.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1679-8) contains supplementary material, which is available to authorized users.

Perioperative Considerations for Patients Diagnosed With Pulmonary Hypertension Undergoing Noncardiac Surgery

The prevalence of pulmonary hypertension (PH) has risen in adults of all races, genders, and ethnicities. PH is a fatal disease that presents many challenges to the perioperative health care team. Through increased knowledge of PH pathophysiological changes and anesthesia medications' effect on PH, perioperative health care teams can conduct a detailed preoperative evaluation to determine appropriate therapies to administer. This will assist the perioperative health care team in reducing the pulmonary vascular resistance, optimizing the matching of right ventricle and pulmonary circulations, and reduce the incidence of intraoperative and postoperative complications.

Echocardiographic assessment of pulmonary artery systolic pressure following treadmill stress testing

Aims

The use of treadmill stress echocardiography (SE) for the diagnosis of nascent pulmonary hypertension (PH) has been hampered by a lack of well-defined, post-exercise pulmonary artery systolic pressure (PASP) values across representative age groups in a normal cohort.

Methods and results

Five hundred and eleven subjects (mean age: 53 ±14, 68% female) with normal resting PASP were included in the study. All participants performed treadmill exercise using the Bruce protocol to a high level of perceived exertion. PASP was calculated before and immediately after exercise using Doppler assessment of tricuspid regurgitation. For the cohort, post-exercise PASP was 39 ± 7 mmHg (range: 23-64 mmHg) representing an increase of 11 ± 6 mmHg (44%) from resting values (P < 0.001). The 95th centile values for post-exercise PASP were calculated for the following age cohorts: <30 years; 46 mmHg, 31-50 years; 50 mmHg, 51-70 years; 52 mmHg, >70 years; 53 mmHg. There was a modest independent correlation between post-exercise PASP and (i) increasing age and (ii) resting PASP (r2 = 0.35 and 0.49, respectively, P = 0.01).

Conclusion

An increase of post-exercise PASP was seen in all patients undergoing SE in this study. Age was directly correlated with post-exercise PASP. Using normative data from healthy controls, treadmill SE-derived post-exercise PASP may be a useful adjunct in the diagnosis of PH.

EXPRESS: Intimacy, Contraception, and Pregnancy Prevention in Patients with Pulmonary Arterial Hypertension: Are We Counseling Our Patients?

Pulmonary arterial hypertension (PAH) is a serious, life-altering condition. Patients who are diagnosed are often of childbearing potential. Given the well-documented risks associated with this condition during pregnancy, as well as risks to the fetus from medications used to treat this disorder, patients should be strongly advised against pregnancy. Despite this, patients still become pregnant, leading to the question of whether care providers are counseling patients and their partners about the risks of pregnancy, methods of contraception, and issues of intimacy on a regular basis. We have conducted a survey of pulmonary hypertension specialist physicians and allied healthcare professionals on their practice patterns related to counseling on intimacy, contraception, and pregnancy prevention. Most respondents indicated they are counseling on these issues to varying degrees, but our survey pointed to several areas where improvements can be made. The most significant barrier to counseling for all respondents was lack of time. Survey respondents reported that a large percentage of the pregnancies seen in their practices were either intentional or due to contraceptive non-compliance. We review specific practical approaches to initiate reproductive health counseling as well as ways to integrate this important aspect of PAH care into regular practice routines and documentation. Protocols regarding pregnancy avoidance and PAH should be developed and become standard procedure.

Natural plant products in treatment of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe disease characterized by progressive remodeling of distal pulmonary arteries and persistent elevation of pulmonary vascular resistance (PVR), which leads to right ventricular dysfunction, heart failure, and eventually death. Although treatment responsiveness for this disease is improving, it continues to be a life-threatening condition. With the clinical efficacy of natural plant products being fully confirmed by years of practice, more and more recognition and attention have been obtained from the international pharmaceutical industry. Moreover, studies over the past decades have demonstrated that drugs derived from natural plants show unique advantages and broad application prospects in PAH treatment, not to mention the historical application of Chinese traditional medicine in cardiopulmonary diseases. In this review, we focus on summarizing natural plant compounds with therapeutic properties in PAH, according to the extracts, fractions, and pure compounds from plants into categories, hoping it to be helpful for basic research and clinical application.

Imaging of pulmonary hypertension: an update

Pulmonary hypertension (PH) is characterized by elevated pulmonary arterial pressure caused by a broad spectrum of congenital and acquired disease processes, which are currently divided into five groups based on the 2013 WHO classification. Imaging plays an important role in the evaluation and management of PH, including diagnosis, establishing etiology, quantification, prognostication and assessment of response to therapy. Multiple imaging modalities are available, including radiographs, computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine, echocardiography and invasive catheter angiography (ICA), each with their own advantages and disadvantages. In this article, we review the comprehensive role of imaging in the evaluation of PH.

Vascular complications in systemic sclerosis: a prospective cohort study

Two major complications in scleroderma patients that cause substantial morbidity and mortality are ischemic digital lesions (DL) and pulmonary hypertension (PH). The clinician's ability to predict which patients will develop these complications is imperfect. We conducted a prospective observational cohort study of 300 patients with scleroderma who were followed for at least a 5-year period. At baseline, patients lacked evidence of PH and were without a current DL. At each 6-month visit, the patient was examined for signs/symptoms of PH and/or a DL. The primary outcomes were (1) PH defined as a mean pulmonary artery pressure ≥ 25 mmHg by right heart catheterization and (2) ≥ 1 DL defined as new onset of severe vascular compromise. Thirty patients (10%) developed PH (11 group 1/PAH, 4 group II, 15 group III) and 69 developed DL. The average time from enrollment until diagnosis of PH was 3.2 ± 2 years. In multivariable analyses, patients who developed PH were more likely to have diffuse disease (HR 3.2, p = 0.004), a forced vital capacity (FVC)/diffusing capacity of the lungs for carbon monoxide (DLCO) ratio > 1.6 (HR 1.7, p = 0.008), and elevated RVSP (HR = 1.07, p = 0.007). Patients who developed PAH were more likely to have a FVC/DLCO ratio > 1.6 (HR = 5.8, p = 0.014), and patients who developed group III PH were less likely to have an elevated FVC (HR = 0.92, p = 0.001). Patients were more likely to develop a DL if they had a history of prior DL (HR = 7.0, p < 0.001), or were men (HR = 2.3, p = 0.007). In a prevalent cohort of scleroderma patients, individuals who develop PH or DL have simple to measure clinical features that can predict these complications years before they occur.

Diagnosing and managing scleroderma-related pulmonary arterial hypertension

Scleroderma is an uncommon autoimmune disease of unknown cause that may affect any organ system in the body. Patients with scleroderma are prone to developing pulmonary complications, including pulmonary arterial hypertension (PAH), that are the leading cause of death in this population. This article describes scleroderma-related PAH and its diagnosis and management.

Role of pulmonary hemodynamics in determining 6-minute walk test result in atrial septal defect: an observational study

Background

The presence of altered pulmonary hemodynamics in adult patients with atrial septal defect (ASD) is common. However, there are no observational studies which evaluate the impact of altered pulmonary hemodynamics on the 6-min walk test (6MWT) result. This study aimed to investigate the role of pulmonary hemodynamics in determining 6MWT result of patients with ASD.

Method

Forty-six consecutive adult patients with ASD were included in this study. Right heart catheterization was performed to obtain the pulmonary hemodynamics profile. Meanwhile, 6MWT was presented as high or low with cut-off point 350 m. Receiver operating characteristic (ROC) was used for analytical methods.

Result

Abnormal functional capacity was indicated by ROC result of mPAP cut-off value of > 24 mmHg (p = 0.0243; AUC = 0.681). The value of PVR > 3.42 woods unit (WU) showed high specificity in determining abnormal functional capacity (p = 0.0069; AUC = 0.713). Flow ratio with cut-off point ≤4.89 had the highest sensitivity (100%) (p = 0.8300; AUC = 0.520).

Conclusion

Pulmonary hemodynamics can serve as an indicator of 6MWT result in adult ASD patients with values of mPAP> 24 mmHg and PVR > 3.42 WU.

Characteristics and survival data from Latvian pulmonary hypertension registry: comparison of prospective pulmonary hypertension registries in Europe

Patient registries are a valuable tool in the research of rare conditions such as pulmonary hypertension (PH). We report comprehensive hemodynamic and survival data of 174 patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), included in the prospective Latvian PH registry over a period of > 9 years. In total, 130 adult PAH patients (75%) and 44 adult CTEPH patients (25%) were enrolled. The median follow-up period was 33 months for PAH and 18 months for CTEPH, P = 0.001. Latvian CTEPH patients had significantly higher plasma levels of B-type natriuretic peptide, higher pulmonary vascular resistance, and lower cardiac index than Latvian PAH patients. Calculated incidence of PAH and CTEPH in Latvia in 2016 was 13.7 and 5.1 cases per million inhabitants, calculated prevalence was 45.7 and 15.7 cases per million inhabitants, respectively. Survival rates at one, three, and five years for PAH patients was 88.0%, 73.3%, and 58.1%, and 83.8%, 59.0%, and 44.2% for CTEPH patients, respectively. We compared our study results with data from European adult PH registries. Latvian PAH patients had the fourth lowest and CTEPH patients the lowest one-year survival rate among European adult PH registries. As most PH registries in Europe are small, yet with equivalent patient inclusion criteria, it would be desirable to combine these registries to produce more reliable and high-quality study results.

New insights into the recognition, classification and management of systemic sclerosis-associated pulmonary hypertension

PURPOSE OF REVIEW

Pulmonary hypertension is a common complication of systemic sclerosis (SSc), and remains a leading cause of morbidity and mortality. We will review recent developments in the recognition, classification and treatment of pulmonary hypertension in SSc.

RECENT FINDINGS

Advances in screening for pulmonary arterial hypertension (PAH) and use of exercise haemodynamics may help to identify pulmonary vascular disease earlier in SSc. Recent studies have led to changes in recommendations for adjunct therapy and selection of pulmonary vasodilators for the treatment of SSc-associated PAH.

SUMMARY

Recent advances in the diagnosis, classification and management of pulmonary hypertension in SSc have continued to improve our understanding of this challenging disease. Ongoing investigation in the pathogenesis of this disease will afford the opportunity to develop targeted therapies to improve outcomes for SSc patients with pulmonary hypertension.

Predictors of poor outcome in patients with pulmonary arterial hypertension: A single center study

OBJECTIVES

Pulmonary arterial hypertension (PAH) is a rare disorder with unfavorable prognosis despite implementation of specific PAH-oriented therapy. The aim of the study was to define predictors of poor prognosis in patients from one center treated according to the Polish National Health Fund program.

PATIENTS AND METHODS

Forty-seven consecutive patients (30 women; aged 39±17 years) with PAH diagnosis were enrolled to the study. Clinical assessment, laboratory measurements, electrocardiogram, echocardiography, 6-minute walk test, 24-hour Holter monitoring, cardiopulmonary exercise test and microvolt T-wave alternans test were performed during routine visits. Eight patients died during 2.6±1.7 years follow-up.

RESULTS

Parametrs which differentiated patients who died were brain natriuretic peptide (BNP) concentration ≥330 pg/mL (sensitivity 88%, specificity 92%, area under the ROC curve [AUC] 0.92); bilirubin concentration ≥1.2 mg/dL (sensitivity 88%, specificity 81%, AUC 0.85); right atrial area ≥21 cm2 (sensitivity 86%, specificity 69%, AUC 0.84), right ventricular (RV) dimension in the apical 4-chamber view ≥47 mm (sensitivity 86%, specificity 86%, AUC 0.85) and RV to left ventricular diastolic diameter ratio ≥1.5 (sensitivity 83%, specificity 84%; AUC 0.85). In multivariate analysis, independent predictors of mortality were higher BNP (p = 0.04) and bilirubin level (p = 0.03), higher right atrial area (p = 0.02) and lower tricuspid annular plane systolic excursion (p = 0.03).

CONCLUSIONS

In PAH patients treated with specific PAH-oriented therapy right atrial enlargement, impaired right ventricular systolic function, as well as increased BNP and bilirubin concentration was associated with an increased mortality risk.

Desmosine and Isodesmosine as a Novel Biomarker for Pulmonary Arterial Hypertension: A Pilot Study

Delayed diagnosis is common in patients with pulmonary arterial hypertension (PAH). Right-sided heart catheterization, the gold standard for diagnosis, is invasive and cannot be applied for routine screening. Some biomarkers have been looked into; however, due to the lack of a clear pathological mechanism linking the marker to PAH, the search for an ideal one is still ongoing. Elastin is a significant structural constituent of blood vessels. Its synthesis involves cross-linking of monomers by 2 amino acids, desmosine and isodesmosine (D&I). Being extremely stable, elastin undergoes little metabolic turnover in healthy individuals resulting in very low levels of D&I amino acids in the human plasma, urine, or sputum. We hypothesized that in PAH patients, the elastin turnover is high; which in turn should result in elevated levels of D&I in plasma and urine. Using mass spectrometry, plasma and urine levels of D&I were measured in 20 consecutive patients with PAH confirmed by cardiac catheterization. The levels were compared with 13 healthy controls. The mean level of total plasma D&I in patients with PAH was 0.47 ng/mL and in controls was 0.19 ng/mL (P = 0.001). The mean levels of total D&I in the urine of PAH patients was 20.55 mg/g creatinine and in controls was 12.78 mg/g creatinine (P = 0.005). The mean level of free D&I in the urine of PAH patients was 10.34 mg/g creatinine and in controls was 2.52 mg/g creatinine (P < 0.001). This is the first study highlighting that the serum and urine D&I has a potential to be a novel screening biomarker for patients with PAH. It paves the way for larger studies to analyze its role in assessing for disease severity and response to treatment.

The impact of slice-reduced computed tomography on histogram-based densitometry assessment of lung fibrosis in patients with systemic sclerosis

Background

To evaluate usability of slice-reduced sequential computed tomography (CT) compared to standard high-resolution CT (HRCT) in patients with systemic sclerosis (SSc) for qualitative and quantitative assessment of interstitial lung disease (ILD) with respect to (I) detection of lung parenchymal abnormalities, (II) qualitative and semiquantitative visual assessment, (III) quantification of ILD by histograms and (IV) accuracy for the 20%-cut off discrimination.

Methods

From standard chest HRCT of 60 SSc patients sequential 9-slice-computed tomography (reduced HRCT) was retrospectively reconstructed. ILD was assessed by visual scoring and quantitative histogram parameters. Results from standard and reduced HRCT were compared using non-parametric tests and analysed by univariate linear regression analyses.

Results

With respect to the detection of parenchymal abnormalities, only the detection of intrapulmonary bronchiectasis was significantly lower in reduced HRCT compared to standard HRCT (P=0.039). No differences were found comparing visual scores for fibrosis severity and extension from standard and reduced HRCT (P=0.051-0.073). All scores correlated significantly (P<0.001) to histogram parameters derived from both, standard and reduced HRCT. Significant higher values of kurtosis and skewness for reduced HRCT were found (both P<0.001). In contrast to standard HRCT histogram parameters from reduced HRCT showed significant discrimination at cut-off 20% fibrosis (sensitivity 88% kurtosis and skewness; specificity 81% kurtosis and 86% skewness; cut-off kurtosis ≤26, cut-off skewness ≤4; both P<0.001).

Conclusions

Reduced HRCT is a robust method to assess lung fibrosis in SSc with minimal radiation dose with no difference in scoring assessment of lung fibrosis severity and extension in comparison to standard HRCT. In contrast to standard HRCT histogram parameters derived from the approach of reduced HRCT could discriminate at a threshold of 20% lung fibrosis with high sensitivity and specificity. Hence it might be used to detect early disease progression of lung fibrosis in context of monitoring and treatment of SSc patients.

Experimental Right Ventricular Hypertension Induces Regional β1-Integrin-Mediated Transduction of Hypertrophic and Profibrotic Right and Left Ventricular Signaling

BACKGROUND

Development of right ventricular (RV) hypertension eventually contributes to RV and left ventricular (LV) myocardial fibrosis and dysfunction. The molecular mechanisms are not fully elucidated.

METHODS AND RESULTS

Pulmonary artery banding was used to induce RV hypertension in rats in vivo. Then, we evaluated cardiac function and regional remodeling 6 weeks after pulmonary artery banding. To further elucidate mechanisms responsible for regional cardiac remodeling, we also mimicked RV hypertensive stress by cyclic mechanical stretching applied to confluent cultures of cardiac fibroblasts, isolated from the RV free wall, septal hinge points, and LV free wall. Echocardiography and catheter evaluation demonstrated that rats in the pulmonary artery banding group developed RV hypertension with leftward septal displacement, LV compression, and increased LV end-diastolic pressures. Picrosirius red staining indicated that pulmonary artery banding induced marked RV fibrosis and dysfunction, with prominent fibrosis and elastin deposition at the septal hinge points but less LV fibrosis. These changes were associated with proportionally increased expressions of integrin-β1 and profibrotic signaling proteins, including phosphorylated Smad2/3 and transforming growth factor-β1. Moreover, mechanically stretched fibroblasts also expressed significantly increased levels of α-smooth muscle actin, integrin-β1, transforming growth factor-β1, collagen I deposition, and wrinkle formation on gel assays, consistent with myofibroblast transformation. These changes were not observed in parallel cultures of mechanically stretched fibroblasts, preincubated with the integrin inhibitor (BTT-3033).

CONCLUSIONS

Experimentally induced RV hypertension triggers regional RV, hinge-point, and LV integrin β1-dependent mechanotransduction signaling pathways that eventually trigger myocardial fibrosis via transforming growth factor-β1 signaling. Reduced LV fibrosis and preserved global function, despite geometrical and pressure aberrations, suggest a possible elastin-mediated protective mechanism at the septal hinge points.

Prognostic value of three-dimensional echocardiographic right ventricular ejection fraction in patients with pulmonary arterial hypertension

Background

Right ventricular (RV) function is an independent predictor of clinical outcomes in patients with pulmonary arterial hypertension (PAH). However, it remains controversial which RV parameter should be measured as an appropriate index for the treatment of PAH. The aim of this study was to identify the most useful parameter that correlates with hemodynamics and predicts clinical outcomes in PAH.

Results

Most of the clinical and echocardiographic RV parameters were significantly correlated with pulmonary vascular resistance (PVR) as well as mean pulmonary arterial pressure (mPAP). Among these, three dimensional right ventricular ejection fraction (3DRVEF) showed the strongest hemodynamic correlation, followed by 6-minute walk distance. Receiver operating characteristic analysis of association with cardiac events including death, hospitalization, and intervention revealed a greater area under the curve for 3DRVEF than for mPAP (0.78 vs. 0.74). Kaplan-Meier analysis showed that patients with 3DRVEF less than 38% had significantly shorter event-free survival than those with greater than 38% (P = 0.0007). Finally, the Cox proportional hazards analysis revealed that 3DRVEF, but not mPAP, was an independent predictor of clinical events in PAH.

Materials and Methods

Eighty-six consecutive patients were enrolled in this study. RV hemodynamic parameters were measured by right heart catheterization (RHC). RV function was assessed using two-dimensional speckle-tracking echocardiography and three-dimensional transthoracic echocardiography (3DTTE) to evaluate RV free wall global strain (RVFS) and RVEF.

Conclusions

RVEF measured by 3DTTE could be a useful parameter for noninvasively assessing RV hemodynamics and predicting the clinical outcomes in PAH patients.

Clinical 'pearls' of maternal critical care Part 2: sickle-cell disease in pregnancy

PURPOSE OF REVIEW

The current review outlines the challenges in managing pregnant women with sickle-cell anemia, who are at risk of becoming critically ill during pregnancy.

RECENT FINDINGS

Sickle obstetric patients pose unique challenges to the anesthetist and intensivist. We discuss the role of prophylactic transfusions for specific indications like acute anemia and twin pregnancies. The management and prevention of vaso-occlusive crises and chest crisis are also outlined. The role of the multidisciplinary team cannot be overstated.Massive obstetric hemorrhage in this population is difficult, and unique considerations such as cell-saver technology and tranexamic acid usage are discussed. Secondary complications such as pulmonary hypertension and stroke are also considered, with a summary of the latest treatment guidelines.

SUMMARY

This is a challenging cohort of pregnant patients who have a significantly increased morbidity and mortality. This review aims to aid management of these patients on the labor ward for both obstetric anesthetists and intensivists.

Chronic intratracheal application of the soluble guanylyl cyclase stimulator BAY 41-8543 ameliorates experimental pulmonary hypertension

Dysfunction of the NO/sGC/cGMP signaling pathway has been implicated in the pathogenesis of pulmonary hypertension (PH). Therefore, agents stimulating cGMP synthesis via sGC are important therapeutic options for treatment of PH patients. An unwanted effect of this novel class of drugs is their systemic hypotensive effect. We tested the hypothesis that aerosolized intra-tracheal delivery of the sGC stimulator BAY41-8543 could diminish its systemic vasodilating effect.Pharmacodynamics and -kinetics of BAY41-8543 after single intra-tracheal delivery was tested in healthy rats. Four weeks after a single injection of monocrotaline (MCT, 60 mg/kg s.c.), rats were randomized to a two-week treatment with either placebo, BAY 41-8543 (10 mg/kg per os (PO)) or intra-tracheal (IT) instillation (3 mg/kg or 1 mg/kg).Circulating concentrations of the drug 10 mg/kg PO and 3 mg/kg IT were comparable. BAY 41-8543 was detected in the lung tissue and broncho-alveolar fluid after IT delivery at higher concentrations than after PO administration. Systemic arterial pressure transiently decreased after oral BAY 41-8543 and was unaffected by intratracheal instillation of the drug. PO 10 mg/kg and IT 3 mg/kg regimens partially reversed pulmonary hypertension and improved heart function in MCT-injected rats. Minor efficacy was noted in rats treated IT with 1 mg/kg. The degree of pulmonary vascular remodeling was largely reversed in all treatment groups.Intratracheal administration of BAY 41-8543 reverses PAH and vascular structural remodeling in MCT-treated rats. Local lung delivery is not associated with systemic blood pressure lowering and represents thus a further development of PH treatment with sGC stimulators.

Modeling of pharmacokinetics, efficacy, and hemodynamic effects of macitentan in patients with pulmonary arterial hypertension

BACKGROUND

Macitentan is the first endothelin receptor antagonist with demonstrated efficacy on morbidity and mortality in pulmonary arterial hypertension (PAH) in the pivotal study SERAPHIN.

METHODS

The pharmacokinetics (PK) of macitentan and its active metabolite, ACT-132577, were characterized in a population model. Efficacy and hemodynamics (pharmacodynamics, PD) were related to PK based on PK/PD modeling.

RESULTS

Sex, age, and body weight influenced the PK to a statistically significant extent. Model-based simulations showed that these variables are clinically not relevant. Concomitant use of PAH medication (PDE-5 inhibitors) did not influence macitentan trough concentration to a relevant extent. Efficacy and hemodynamics showed clear differences from placebo for macitentan concentrations on 3 and 10 mg with consistent superior effects for 10 mg. After 6 months, PAH patients showed model-predicted 6-min walk distance (6-MWD) improvements of 1.0 m on placebo compared to 29.8 and 34.1 m on 3 and 10 mg of macitentan, respectively. Higher macitentan concentrations were associated with reductions in pulmonary vascular resistance (PVR), mean right atrial and pulmonary arterial pressure, and total pulmonary resistance (TPR) and increases in cardiac index (CI) and mixed venous oxygen saturation. Statistical significance was determined for PVR, TPR, and CI but not for 6-MWD. In addition, PVR showed more pronounced differences between active treatment and placebo than 6-MWD.

CONCLUSIONS

Modeling identified statistically significant inter-patient differences; simulations to assess the magnitude of the effects permitted clinical judgment. The same approach will allow for extrapolation to children. Hemodynamic markers might be better markers of treatment effects than 6-MWD.

TRIAL REGISTRATION

The SERAPHIN study and its open-label extension are registered with ClinicalTrials.gov with identifiers NCT00660179 (https://www.clinicaltrials.gov/ct2/show/NCT00660179) and NCT00667823 (https://clinicaltrials.gov/ct2/show/NCT00667823) and with EudraCT with identifiers 2007-002440-14 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=2007-002440-14) and 2007-003694-27 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=2007-003694-27).

Approach to Pulmonary Hypertension: From CT to Clinical Diagnosis

Pulmonary hypertension (PH) is a condition characterized by increased pressure in the pulmonary circulation. It may be idiopathic or arise in the setting of other clinical conditions. Patients with PH tend to present with nonspecific cardiovascular or respiratory symptoms. The clinical classification of PH was recently revised at the World Health Organization symposium in Nice, France, in 2013. That consensus statement provided an updated classification based on the shared hemodynamic characteristics and management of the different categories of PH. Some features seen at computed tomography (CT) can suggest a subtype or probable cause of PH that may facilitate placing the patient in the correct category. These features include findings in the pulmonary arteries (peripheral calcification, peripheral dilatation, eccentric filling defects, intra-arterial soft tissue), lung parenchyma (centrilobular nodules, mosaic attenuation, interlobular septal thickening, bronchiectasis, subpleural peripheral opacities, ground-glass opacities, diffuse nodules), heart (congenital lesions, left heart disease, valvular disease), and mediastinum (hypertrophied bronchial arteries). An approach based on identification of these CT features in patients with PH will allow the radiologist to play an important role in diagnosis and help guide the clinician in management of PH. ^©RSNA, 2018.

Definition, epidemiology and registries of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a subcategory of pulmonary hypertension (PH) that comprises a group of disorders with similar pulmonary vascular pathology. Though PH is common, the estimated incidence of IPAH is 1-3 cases per million, making it a rare disease. The hemodynamic definition of PAH is a mean pulmonary artery pressure at rest >OR = 25 mm Hg in the presence of a pulmonary capillary wedge pressure <OR = 15 mmHg with pulmonary vascular resistance (PVR) greater than 3 WU. Specific maneuvers during right heart catheterization can be utilized to disclose vasoreactivity and heart failure with preserved ejection fraction, which have implications for management. The inherent complexity in studying a rare disease that exhibits clinical overlap with a common syndrome necessitated the creation of registries. These registries have been indispensable in the characterization and mapping of the natural history of the disease. Equations and risk calculators derived from registries have given clinicians a basis for risk stratification and prognostication. The sequential accumulation of data since the registries began in the 1980s allows for comparisons to be made. Patients who are differentiated by treatment eras and environments can be contrasted. Variability among inclusion criteria similarly allows for comparisons of these subpopulations. This article provides an overview of available registries, highlights insights provided by each and discusses key issues around the interpretation and extrapolation of data from PAH registries. Registries have allowed us to appreciate the improvement in survival afforded by modern therapy and enhanced detection of this disease. Moving forward, a more global approach to registries is needed, as is enhanced collaboration and centralization.

Pulmonary hypertension associated with lung diseases and hypoxemia

Pulmonary hypertension that develops in the setting of underlying lung diseases such as COPD or idiopathic pulmonary fibrosis (IPF) is associated with decreased functional status, worsening hypoxemia and quality of life, and increased mortality. This complication of lung disease is complex in its origin and carries a unique set of diagnostic and therapeutic issues. This review attempts to provide an overview of mechanisms associated with the onset of pulmonary hypertension in COPD and IPF, touches on appropriate evaluation, and reviews the state of knowledge on treating pulmonary hypertension related to underlying lung disease.

Exercise-Induced Pulmonary Hypertension: Translating Pathophysiological Concepts Into Clinical Practice

Exercise stress testing of the pulmonary circulation for the diagnosis of latent or early-stage pulmonary hypertension (PH) is gaining acceptance. There is emerging consensus to define exercise-induced PH by a mean pulmonary artery pressure > 30 mm Hg at a cardiac output < 10 L/min and a total pulmonary vascular resistance> 3 Wood units at maximum exercise, in the absence of PH at rest. Exercise-induced PH has been reported in association with a bone morphogenetic receptor-2 gene mutation, in systemic sclerosis, in left heart conditions, in chronic lung diseases, and in chronic pulmonary thromboembolism. Exercise-induced PH is a cause of decreased exercise capacity, may precede the development of manifest PH in a proportion of patients, and is associated with a decreased life expectancy. Exercise stress testing of the pulmonary circulation has to be dynamic and rely on measurements of the components of the pulmonary vascular equation during, not after exercise. Noninvasive imaging measurements may be sufficiently accurate in experienced hands, but suffer from lack of precision, so that invasive measurements are required for individual decision-making. Exercise-induced PH is caused either by pulmonary vasoconstriction, pulmonary vascular remodeling, or by increased upstream transmission of pulmonary venous pressure. This differential diagnosis is clinical. Left heart disease as a cause of exercise-induced PH can be further ascertained by a pulmonary artery wedge pressure above or below 20 mm Hg at a cardiac output < 10 L/min or a pulmonary artery wedge pressure-flow relationship above or below 2 mm Hg/L/min during exercise.

Impact of systolic pulmonary artery pressure on all-cause mortality in elderly cardiac patients

OBJECTIVE

Elevated systolic pulmonary artery pressure (sPAP) is common among elderly patients with cardiac and pulmonary diseases. The lowest level of sPAP associated with increased mortality rate in octogenarians with cardiac diseases is however not sufficiently studied. Therefore, the present study aimed to identify the lowest level of sPAP associated with increased 5-year all-cause mortality in this patient group.

DESIGN

Of 538 octogenarians presented at the three Sahlgrenska University Hospitals (Sahlgrenska, Östra and Mölndal) with either congestive heart failure (CHF) or acute coronary syndrome (ACS), only 302 patients who had undergone echocardiography with data on sPAP were included in the present study. In order to identify the lowest level of sPAP associated with increased mortality rate, Cox proportional-hazard regression multivariable models were built for sPAP levels as low as 30 mmHg and upward with 5 mmHg intervals.

RESULTS

sPAP >35 mmHg was identified as the lowest level associated with increased 5-year all-cause mortality (HR = 1.7, 95% of CI = 1.1-2.6 and p = .013). Every increase of 5 mmHg in sPAP was associated with a 10% increased relative risk for all-cause mortality.

CONCLUSIONS

In octogenarians with cardiac diseases the lowest level of sPAP associated with increased all-cause mortality was >35 mmHg and the mortality rate increased with increasing sPAP.

Is there a learning effect when the 6-minute walk test is repeated in people with suspected pulmonary hypertension?

The aim of the study was to determine if there was a difference in 6-minute walk distance (6MWD) when two 6-minute walk tests (6MWTs) were performed at the initial assessment prior to attendance at the pulmonary hypertension (PH) clinic and at the 6-month follow-up. Two 6MWTs were performed at both visits on a 32-m continuous track in the physiotherapy hospital outpatient setting using standard instructions and encouragement. Two hundred and fourteen participants completed two 6MWTs at the initial assessment and 71 participants at the 6-month follow-up (mean (standard deviation) age: 57 (16) years; body mass index: 27 (6) kg/m²). Using the better 6MWT, the mean distances walked were 429 (136) and 447 (130) m, respectively. There was a significant increase in 6MWD when a second 6MWT was performed at initial assessment (mean difference [95% confidence interval (CI)]: 19 m (14–24), p < 0.001) and at the follow-up (mean difference [95% CI]: 19 m (10–27), p < 0.001) but not in those who walked <300 m at the initial assessment (mean difference [95% CI]: 9 m (−5 to 22), p = 0.208). There were no adverse events during testing. Prior to attendance at the PH Clinic when people are asked to perform the 6MWT for the first time and at the 6-month follow-up, two walk tests should be performed in order to eliminate a learning effect and to ensure accuracy of measurement.

Prognostic relevance of elevated pulmonary arterial pressure assessed non-invasively: Analysis in a large patient cohort with invasive measurements in near temporal proximity

Background

The clinical relevance of non-invasively derived pulmonary arterial pressure (PAP) by Doppler echocardiography (DE) has been questioned in the past. However, transthoracic echocardiography is used as a cornerstone examination for patients with dyspnea and suspected pulmonary hypertension (PH). This study aimed to evaluate the prognostic value of non-invasive assessed PAP in a large population of patients with known or suspected cardiopulmonary disease.

Methods

The analyses are based on data of patients of a tertiary cardiology center that received right heart catheterization (RHC) as well as non-invasively assessed PAP by DE within five days, and includes serological and clinical parameters in a retrospective follow-up for up to eight years.

Results

Of 1,237 patients, clinical follow-up was possible in 1,038 patients who were included in the statistical analysis. The mean-follow up time was 1,002 days. The composite endpoint of heart transplantation (HTx) or death occurred in n = 308 patients. Elevated PAP measured non-invasively as well as invasively had significant prognostic impact (hazard ratio (HR) 2.32; 95% confidence interval (CI) 1.78–3.04; χ² = 37.9; p<0.001 versus HR 2.84; 95%CI 2.11–3.82; χ² = 51.9; p<0.001, respectively). By multivariate analysis, NYHA functional class, N-terminal pro-brain natriuretic peptide, cardiac troponin T, left ventricular ejection fraction, and right ventricular dysfunction remained independently predictive. Incremental prognostic information in a multimodal approach was highly relevant.

Conclusions

In this comprehensive study, elevated pulmonary arterial pressure measured by DE offers similar prognostic information on survival or need for HTx as right heart catheterization. Furthermore, the addition of functional capacity and serological biomarkers delivered incremental prognostic information.

Impaired systemic oxygen extraction in treated exercise pulmonary hypertension: a new engine in an old car?

Ambrisentan in 22 patients with pulmonary hypertension diagnosed during exercise (ePH) improved pulmonary hemodynamics; however, there was only a trend toward increased maximum oxygen uptake (VO₂max) secondary to decreased maximum exercise systemic oxygen extraction (Ca-vO₂). We speculate that improved pulmonary hemodynamics at maximum exercise “unmasked” a pre-existing skeletal muscle abnormality.

Lung Transplant in Patients with Scleroderma Compared with Pulmonary Fibrosis. Short- and Long-Term Outcomes

RATIONALE

Patients with advanced lung disease due to systemic sclerosis have long been considered suboptimal and often unacceptable candidates for lung transplant.

OBJECTIVES

To examine post-lung transplant survival of patients with systemic sclerosis compared with patients with pulmonary fibrosis and to identify risk factors for 1-year mortality.

METHODS

In a retrospective cohort study, we compared post-lung transplant outcomes of 72 patients with scleroderma with those of 311 patients with pulmonary fibrosis between June 2005 and September 2013 at our institution. Actuarial survival estimates were calculated using Kaplan-Meier curves. In Cox regression models, we determined risk factors for post-transplant mortality, controlling for whether patients had scleroderma or pulmonary fibrosis.

MEASUREMENTS AND MAIN RESULTS

Post-transplant survival did not differ significantly between scleroderma and pulmonary fibrosis at year 1 (81% scleroderma vs. 79% pulmonary fibrosis; P = 0.743), at year 5 conditional on 1-year survival (66% vs. 58%; P = 0.249), or overall (P = 0.385). In multivariate analysis, body mass index greater than or equal to 35 kg/m(2) predicted poor 1-year survival in pulmonary fibrosis (hazard ratio, 2.76; P = 0.003). Acute cellular rejection-free survival did not differ significantly between the scleroderma and pulmonary fibrosis cohorts. Patients with scleroderma had significantly better bronchiolitis obliterans syndrome stage 1 or higher-free survival than did patients with pulmonary fibrosis.

CONCLUSIONS

Our findings that 1- and 5-year survival rates of patients with scleroderma were similar to those of patients with pulmonary fibrosis indicate that lung transplant is a reasonable treatment option in selected patients with scleroderma.

Prevalence of pulmonary hypertension in systemic lupus erythematosus: a meta-analysis

BACKGROUND AND AIMS

Pulmonary hypertension (PH) has been suggested to be associated with systemic lupus erythematosus (SLE). However, the results of prevalence studies on PH in SLE vary substantially. To derive a more precise estimation on the prevalence of PH in SLE, a meta-analysis was performed.

METHODS

Relevant literatures were searched in PubMed and EMBASE until November 2017. A total of 1366 articles were obtained after searching databases, and 23 studies were finally included in the meta-analysis. Heterogeneity test was performed, and publication bias was evaluated.

RESULTS

The result of analysis in random effect model showed that the pooled prevalence was 8% (95%CI 5-12%). There was no evidence of publication bias (p = 0.51). To evaluate the stability of our results, sensitivity analyses were performed, and the results showed no significant change when any one study was excluded. Subgroup analyses demonstrated that there were significant differences in PH prevalence in SLE patients of different gender, age, regions, year of publication, and diagnostic methods.

CONCLUSIONS

PH is prevalent in SLE patients, but it was significantly different between different gender, age, regions, year of publication, and diagnostic methods.

Potential benefit of bosentan therapy in borderline or less severe pulmonary hypertension secondary to idiopathic pulmonary fibrosis-an interim analysis of results from a prospective, single-center, randomized, parallel-group study

Background

No drugs have been approved for the treatment of patients with pulmonary hypertension (PH) secondary to idiopathic pulmonary fibrosis (IPF), particularly those with idiopathic honeycomb lung. This study was conducted to investigate the long-term efficacy and safety of bosentan for PH based on changes in prognosis and respiratory failure.

Methods

IPF patients with borderline or less severe PH and completely organized honeycomb lung were randomized (1:1) to bosentan or no treatment for PH for 2 years and assessed at baseline and every 6 months for respiratory failure, activities of daily living (ADL), lung and heart functions by right cardiac catheterization, and other parameters. An interim analysis was performed, however, following detection of a significant survival benefit favoring bosentan therapy.

Results

Significant differences were noted for the bosentan-treated (n = 12) vs. untreated (n = 12) groups in hospital-free survival (603.44 ± 50.074 days vs. 358.87 ± 68.65 days; hazard ratio [HR], 0.19; P = 0.017) and overall survival (671 days vs. 433.78 ± 66.98 days; HR, 0.10; P = 0.0082). Again, significant improvements were noted for the bosentan-treated group from baseline to month 6 or 12 in several indices in ADL, pulmonary circulation, and %DLCO. Without requiring O₂ inhalation, bosentan was associated with no increase but a trend toward a decrease in adverse events and an improvement in respiratory status.

Conclusions

Bosentan tended to improve prognosis and ADL without worsening respiratory failure in IPF patients with borderline or less severe PH and completely organized honeycomb lung alone.

Trial registration

This study was registered on December 18, 2010 with UMIN-CTR Clinical Trial as UMIN000004749 to investigate the long-term influence of bosentan on cardiac function, as well as its cardioprotective efficacy and safety, in patients with pulmonary hypertension secondary to concurrent COPD and IPF, respectively.

Electronic supplementary material

The online version of this article (doi: 10.1186/s12890-017-0523-2) contains supplementary material, which is available to authorized users.

Predicting Peak Oxygen Uptake From the 6-Minute Walk Test in Patients With Pulmonary Hypertension

PURPOSE

To determine whether the 6-minute walk test (6MWT) is a predictor of peak oxygen uptake ((Equation is included in full-text article.)O2) in patients with idiopathic pulmonary arterial hypertension (IPAH).

METHODS

A total of 157 patients treated for IPAH completed a 6MWT in accordance with American Thoracic Society standards. Heart rate, pulse oximetry, and Borg rating of perceived exertion were determined at baseline and posttest. A cardiopulmonary exercise test (CPET) was performed on a cycle ergometer using a ramp protocol. Participants were stratified post hoc by age into 3 groups: children (n = 26), adolescents (n = 49), and adults (n = 82). Multiple linear regression analysis was performed to predict peak (Equation is included in full-text article.)O2 from the 6MWT.

RESULTS

The regression equation generated for the children was the only model to strongly predict peak (Equation is included in full-text article.)O2 (r = 0.87; P < .001). Similar models for adolescent (r = 0.59; P < .001) and adult groups (r = 0.68; P < .001) did not achieve the same level of correlation.

CONCLUSION

Six-Minute Walk Test was able to accurately predict peak (Equation is included in full-text article.)O2 in children (6-12 years) with IPAH; however, the model was weaker for predicting peak (Equation is included in full-text article.)O2 in older populations. These findings suggest that 6MWT may be as valid a test for predicting peak (Equation is included in full-text article.)O2 in children with IPAH as CPET measured peak (Equation is included in full-text article.)O2. In older IPAH populations, CPET is the only reliable method for the evaluation of peak (Equation is included in full-text article.)O2.

Pulmonary Hypertension in the Era of Mechanical Circulatory Support

Left heart disease (LHD) represents the most common cause of pulmonary hypertension (PH), and is associated with worse prognosis compared with LHD without PH. In addition, PH due to LHD may prevent patients from receiving heart transplantation, because of risk of perioperative right ventricular failure. Current literature lacks comprehensive descriptions and management strategies of PH due to LHD. In this review, we summarize the literature that is available to highlight the definition, pathogenesis, and prognosis of PH due to LHD. Furthermore, we discuss the use of mechanical circulatory support (MCS) in this population. Finally, we provide recommendations regarding the management and reassessment of PH due to LHD in the specific context of MCS.