Chronic Thromboembolic Pulmonary Hypertension: Epidemiology, Diagnosis, and Management

Tissue factor regulates autophagy in pulmonary artery endothelial cells from chronic thromboembolic pulmonary hypertension rats via the p38 MAPK-FoxO1 pathway

AIMS

To detect the expression of autophagy components, p38 MAPK (p38) and phosphorylated forkhead box transcription factor O-1 (pFoxO1) in pulmonary vascular endothelial cells of chronic thromboembolic pulmonary hypertension (CTEPH) rats and to investigate the possible mechanism through which tissue factor (TF) regulates autophagy.

METHODS

Pulmonary artery endothelial cells (PAECs) were isolated from CTEPH (CTEPH group) and healthy rats (control group (ctrl group)) which were cocultured with TF at different time points including 12 h, 24 h, 48 h and doses including 0 nM,10 nM, 100 nM, 1µM, 10µM, 100µM and cocultured with TFPI at 48 h including 0 nM, 2.5 nM, 5 nM. The expression of forkhead box transcription factor O-1 (FoxO1), pFoxO1, p38, Beclin-1 and LC3B in PAECs was measured. Coimmunoprecipitation (co-IP) assays were used to detect the interaction between FoxO1 and LC3.

RESULTS

The protein expression of p-FoxO1/FoxO1 was significantly lower in the CTEPH groups (cocultured with TF from 0 nM to 100 µM) than in the ctrl group at 12 h, 24 h, and 48 h (P < 0.05) and was significantly lower in the CTEPH groups (cocultured with TFPI from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of p38 in the CTEPH groups treated with 0 nM, 10 nM, 100 nM or 1 µM TF for 48 h significantly increased than ctrl groups (P < 0.05) and was significantly increased in the CTEPH groups (cocultured with TFPI concentration from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of Beclin1 at the same concentration (cocultured with TF from 0 nM to 100 µM) was significantly lower in the CTEPH groups than ctrl groups after 24 h and 48 h (P < 0.05) and was significantly decreased in the CTEPH groups (cocultured with TFPI concentration from 2.5 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of LC3-II/LC3-I at the same concentration (cocultured with TF 0 nM, 1 µM, 10 µM, and 100 µM) was significantly lower in the CTEPH than in the ctrl groups after 12 h (P < 0.05) and was significantly lower in the CTEPH groups (cocultured with TFPI concentration from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). There were close interactions between FoxO1 and LC3 in the control and CTEPH groups at different doses and time points.

CONCLUSION

The autophagic activity of PAECs from CTEPH rats was disrupted. TF, FoxO1 and p38 MAPK play key roles in the autophagic activity of PAECs. TF may regulate autophagic activity through the p38 MAPK-FoxO1 pathway.

External validation of the InShape II study algorithm for exclusion of chronic thromboembolic pulmonary hypertension in patients with pulmonary thromboembolism

BACKGROUND AND AIM

The most severe long-term complication of pulmonary embolism (PE) is chronic thromboembolic pulmonary hypertension (CTEPH), and its early diagnosis often requires numerous diagnostic tests. The InShape II study proposes an early screening algorithm that aims to reduce the number of echocardiographic studies. The objective of our study is to validate this algorithm in our patient cohort.

MATERIALS AND METHODS

We retrospectively analyzed patients admitted to Hospital Rey Juan Carlos between November 2017 and February 2020, who were diagnosed with PE based on computed tomography angiography (CTA). Patients were followed for at least one year, and clinical, laboratory, and complementary test data were collected at three months and one year. The InShape II algorithm was applied to these patients to validate its results.

RESULTS

During the study period, 236 patients were diagnosed with PE, of which 137 were excluded. The algorithm was validated in 99 patients. Applying the InShape II score, 19 echocardiograms would have been performed (three of them with intermediate-high probability of CTEPH), while 80 echocardiograms would have been avoided (two of them with intermediate-high probability). This yielded a sensitivity of 60% and a specificity of 83% for the score, with an area under the curve (AUC) of 0.715 (95% CI: 0.472-0.958).

CONCLUSIONS

Our results support the notion that the InShape II algorithm could be a useful tool for initial screening of CTEPH in low-incidence settings, as it would avoid unnecessary echocardiograms that do not provide additional value.

Identification of Ferroptosis-related potential biomarkers and immunocyte characteristics in Chronic Thromboembolic Pulmonary Hypertension via bioinformatics analysis

BACKGROUND

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is a form of pulmonary hypertension with a high mortality rate. A new type of iron-mediated cell death is Ferroptosis, which is characterized by the accumulation of lethal iron ions and lipid peroxidation leading to mitochondrial atrophy and increased mitochondrial membrane density. Now, there is a lack of Ferroptosis-related biomarkers (FRBs) associated with pathogenic process of CTEPH.

METHODS

The differentially expressed genes (DEGs) of CTEPH were obtained by GEO2R. Genes related to Ferroptosis were obtained from FerrDb database. The intersection of Ferroptosis and DEGs results in FRBs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed in Database for Annotation, Visualization and Integrated Discovery (DAVID) database. The optimal potential biomarkers for CTEPH were analyzed by least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) machine learning. The four hub genes were verified from the Gene Expression Omnibus (GEO) dataset GSE188938. Immune infiltration was analyzed by CIBERSORT. SPSS software was used to analyze the Spearman rank correlation between FRBs identified and infiltration-related immune cells, and p < 0.05 was considered as statistically significant.

RESULTS

In this study, potential genetic biomarkers associated with Ferroptosis in CTEPH were investigated and explored their role in immune infiltration. In total, we identified 17 differentially expressed Ferroptosis-associated genes by GEOquery package. The key FRBs including ARRDC3, HMOX1, BRD4, and YWHAE were screened using Lasso and SVM-RFE machine learning methods.Through gene set GSE188938 verification, only upregulation of gene ARRDC3 showed statistical difference. In addition, immune infiltration analysis using the CIBERSORT algorithm revealed the infiltration of Eosinophils and Neutrophils in CTEPH samples was less than that in the control group. And correlation analysis revealed that ARRDC3 was positively correlated with T cells follicular helper (r = 0.554, p = 0.017) and negatively correlated with Neutrophils (r = -0.47, p = 0.049).

CONCLUSIONS

In conclusion, ARRDC3 upregulation with different immune cell infiltration were involved in the development of CTEPH. ARRDC3 might a potential Ferroptosis-related biomarker for CTEPH treatment. This study provided a new insight into pathogenesis CTEPH.

The angiogenic gene profile of pulmonary endarterectomy specimens: Initial study

Objectives

The underlying mechanisms for the development of chronic thromboembolic pulmonary hypertension and prognostic biomarkers are not clear yet. Thus, our aim is to assess and identify new biomarkers for the expression of 84 key genes linked to angiogenesis.

Methods

Patients who had levels more than 1000 dynes·sec·cm^-5 were included in the test group, and the other patients were included in the control group. Twelve specimens were taken from the patients. RT² Profiler PCR Array (Qiagen) was used to quantify the expression of the 84 key genes.

Results

Eight patients (6 male, 2 female, median age 54.4 ± 13.1 years) who underwent pulmonary endarterectomy were included. Pulmonary vascular resistance improved significantly from 811 ± 390 dyn/s/cm^-5 to 413.3 ± 144.9 dyn/s/cm^-5 (P < .005). A difference was also detected in median mean pulmonary arterial pressure, which decreased from 49.8 ± 9 mm Hg to 32.62 ± 2.50 mm Hg (P > .005) after surgery. Median length of hospital stay was 11.62 ± 2.97 days. The test group had a distinct pattern of impaired angiogenic and antiangiogenic genes. The expression levels of TGFA, TGFB1, THBS2, THBS1, TGFBR1, SERPINE1, SERPINF1, TGFB2, TIMP2, VEGFC, IFNA1, TNF, CXCL10, NOS3, IGF1, and MMP14 were downregulated in the specimens from the patients who had higher pulmonary vascular resistance values, whereas some genes, including PDGFA, showed upregulation that was statistically nonsignificant in the same group.

Conclusions

These results can lead to the development of new markers that could predict adverse outcomes of patients with CTEPH. Identification of new markers that are related to worse outcomes would enable screening patients for early diagnosis and treatment.

The value of ventilation/perfusion scanning and CT pulmonary angiography in predicting chronic thromboembolic pulmonary hypertension after acute pulmonary embolism: a one-year follow-up study

To investigate the value of ventilation/perfusion (V/Q) scanning and CT pulmonary angiography (PA) in predicting CTEPH development after acute pulmonary embolism (APE). This study was performed in APE patients who had undergone both V/Q and CT PA after 3-month anticoagulation. The residual pulmonary obstructions were assessed based on V/Q and CT PA, and then recorded as pulmonary perfusion detect score (PPDs) and CT pulmonary artery obstruction index (PAOI). The predictive performance of PPDs and CT PAOI for CTEPH were determined and risk factors for predicting CTEPH development were identified. A total of 235 patients with initial diagnosis of APE were included in this study. ROC analysis showed that the AUCs of the PPDs and CT PAOI were 0.957 and 0.895, with corresponding cut-off values of 20.50% and 17.50% for predicting CTEPH development. Neither sensitivity nor specificity differed significantly between PPDs and CT PAOI (Sensitivity: 92.00% vs. 80.00%, P = 0.25; Specificity: 88.10% vs. 89.52%, P = 0.69). The univariable and multivariable logistic regression analysis demonstrated that pulmonary arterial hypertension confirmed by echocardiography at initial APE diagnosis (OR: 6.16, 95%CI: 1.31-29.02, P = 0.02), a PPDs of > 20.50% (OR: 22.95, 95%CI: 2.37-222.19, P = 0.007), and a CT PAOI of > 17.50% (OR: 9.98, 95%CI: 2.06-48.49, P = 0.004) were associated with CTEPH development. Both V/Q and CT PA after 3-month anticoagulation for APE showed great performance in predicting CTEPH development, and V/Q scanning has a tendency to be more sensitive but less specific than CT PA. The residual pulmonary embolism detected by V/Q and CT PA was associated with an increased risk of CTEPH development.

Chronic Thromboembolic Pulmonary Hypertension: An Observational Study

Background and Objectives: Chronic thromboembolic pulmonary hypertension (CTEPH) has a high mortality. The treatment of CTEPH could be balloon pulmonary angioplasty (BPA), medical (MT) or pulmonary endarterectomy (PEA). This study aims to assess the clinical characteristics of CTEPH patients, surgically or medically treated, in a pulmonology referral center. Materials and Methods: A total of 124 patients with PH with suspected CTEPH (53 male subjects and 71 female subjects; mean age at diagnosis 67 ± 6) were asked to give informed consent and then were evaluated. The presence of CTEPH was ascertained by medical evaluations, radiology and laboratory tests. Results: After the evaluation of all clinical data, 65 patients met the inclusion criteria for CTEPH and they were therefore enrolled (22 males and 43 females; mean age at diagnosis was 69 ± 8). 26 CTEPH patients were treated with PEA, 32 with MT and 7 with BPA. There was a statistically significant age difference between the PEA and MT groups, at the time of diagnosis, the PEA patients were younger than the MT patients, whereas there was no statistically significant difference in other clinical characteristics (e.g., smoking habit, thrombophilia predisposition), as well as functional and hemodynamic parameters (e.g., 6-min walk test, right heart catheterization). During three years of follow-up, no patients in the PEA groups died; conversely, eleven patients in the MT group died during the same period (p < 0.05). Furthermore, a significant decrease in plasma BNP values and an increase in a meter at the six-minute walk test, 1 and 3 years after surgery, were observed in the PEA group (p < 0.05). Conclusions: This study seems to confirm that pulmonary endarterectomy (PEA) can provide an improvement in functional tests in CTEPH.

Chronic Thromboembolic Pulmonary Hypertension: An Update

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease observed in a small proportion of patients after acute pulmonary embolism (PE). CTEPH has a high morbidity and mortality rate, related to the PH severity, and a poor prognosis, which mirrors the right ventricular dysfunction involvement. Pulmonary endarterectomy (PEA) reduces pulmonary vascular resistance, making it the treatment of choice and should be offered to operable CTEPH patients, as significant symptomatic and prognostic improvement has been observed. Moreover, these patients may also benefit from the advances made in surgical techniques and pulmonary hypertension-specific medication. However, not all patients are eligible for PEA surgery, as some have either distal pulmonary vascular obstruction and/or significant comorbidities. Therefore, surgical candidates should be carefully selected by an interprofessional team in expert centers. This review aims at making an overview of the risk factors and latest developments in diagnostic tools and treatment options for CTEPH.

Infrared Spectroscopy in Differential Diagnosis of Pulmonary Embolism

The aim of the study was to assess the effectiveness of infrared spectroscopy for verification of pulmonary embolism (PE) and a number of similar diseases.

Materials and Methods

Infrared spectroscopy was used to investigate blood serum of 19 healthy volunteers and 30 patients with intraoperatively confirmed PE as well as with chronic obstructive pulmonary disease (COPD) (n=10), pneumonia (n=10), tuberculosis (n=10), lung abscess (n=10) and lung cancer (n=10), acute disorder of cerebral circulation (ADCC) (n=10), ischemic heart disease (IHD) (n=10). Peak height ratios of absorption band were taken as diagnostic parameters (cm^-1/сm^-1): P₁ - 1160/1165; P₂ - 1165/1070; P₃ - 1165/1150; P₄ - 1165/1050; P₅ - 1100/1050; P₆ - 1025/1165. These parameters of IR spectrum are significant for the given nosology.

Results

The calculated indicators have demonstrated statistically significant difference of IR spectra parameters for the studied nosologies (p<0.001) even on the small samples supplementing each other and enabling step-by-step exclusion of lung abscess and pulmonary tuberculosis, COPD and pneumonia, cancer, IHD, ADCC, and PE.The presented radar charts, built with consideration of the values of all peak height ratios of the absorption bands with diagnostically significant maxima, provided the possibility to visualize the IR profiles making the differentiation of PE and its clinical analogs not only more objective and reliable but also more explicit and compelling.

Conclusion

Infrared spectroscopy is a potentially effective method of PE differential diagnosis. Sample expansion will allow researchers to evaluate the sensitivity and specificity of this technique compared to the existing standard schemes of PE verification.

Pulmonary Thromboendarterectomy in Klinefelter Syndrome. Literature Review

Klinefelter syndrome  is a form of male hypogonadism due to testicular sclerohyalinosis with atrophy and azoospermia, which is the most common cause of male infertility. The syndrome is usually accompanied by metabolic, morphological, and neurobehavioral manifestations; Venous thromboembolic diseases such as deep vein thrombosis and pulmonary embolism. The existence of chronic thromboembolic pulmonary hypertension in patients with Klinefelter syndrome   is scarce in the literature. We present the imaging and genetic analysis of a 37 -year-old male with a history of deep vein thrombosis who was admitted for exertional dyspnea.

In situ Pulmonary Artery Thrombosis: A Previously Overlooked Disease

Pulmonary thromboembolism (PTE) is the third leading cause of death in cardiovascular diseases. PTE is believed to be caused by thrombi detached from deep veins of lower extremities. The thrombi travel with systemic circulation to the lung and block pulmonary arteries, leading to sudden disruption of hemodynamics and blood gas exchange. However, this concept has recently been challenged by accumulating evidence demonstrating that de novo thrombosis may be formed in pulmonary arteries without deep venous thrombosis. On the other hand, chronic thromboembolic pulmonary hypertension (CTEPH), a subtype of pulmonary hypertension, could have different pathogenesis than traditional PTE. Therefore, this article summarized and compared the risk factors, the common and specific pathogenic mechanisms underlying PTE, in situ pulmonary artery thrombosis, and CTEPH at molecular and cellular levels, and suggested the therapeutic strategies to these diseases, aiming to facilitate understanding of pathogenesis, differential diagnosis, and precision therapeutics of the three pulmonary artery thrombotic diseases.

Evaluation of Diagnostic Accuracy and Radiation Exposure of Dual-Energy Computed Tomography (DECT) in the Course of Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

PURPOSE

 The purpose of this study was to assess the diagnostic accuracy of computed tomography pulmonary angiogram (CTPA) including dual energy and reconstruction of iodine maps for diagnosing CTEPH. This method for detecting embolisms and perfusion failures was compared with V/Q-SPECT. An additional purpose was to compare the applied radiation dose of both techniques.

MATERIALS AND METHODS

 71 patients (49 women) with suspected CTEPH were included in this prospective study. The patients received a V/Q-SPECT and a dual-energy CTPA. Iodine maps were reconstructed from the data set. CTPA and the iodine maps were read by an experienced radiologist unaware of the clinical information as well as the results of the V/Q-SPECT. Results were compared to the V/Q-SPECT. DLP and the applied amount of radionuclides (MAA, Technegas) were obtained for comparison of radiation dose.

RESULTS

 For the diagnosis of CTEPH, the sensitivity of DECT was 1.000, specificity 0.966, PPV 0.867 and NPV 1.000, respectively. There was not a considerable difference in the x-ray exposure between the DECT examination and the V/Q-SPECT (1.892 mSv vs. 1.911 mSv; p = 0.6115). Both examination modalities were highly consistent regarding the classification of pathological segments (1177/1278 segments, 92,09 %, κ = 0,5938).

CONCLUSION

 This study presents the DECT, in combination with reconstructed iodine maps, as a potential alternative to the current imaging technique of first choice, V/Q-SPECT. For creating future prospective diagnostic algorithms, the implementation of DECT screening with iodine maps should be considered.

KEY POINTS

· DECT correctly identified all CTEPH patients.. · There is substantial agreement between DECT and V/Q-SPECT in the classification of pathological segments.. · There is no significant difference in radiation exposure during DECT examination and V/Q-SPECT examination.. · Reduced radiation dose does not negatively impact image quality..

CITATION FORMAT

· Schüßler A, Richter M, Tello K et al. Evaluation der diagnostischen Genauigkeit und der Strahlendosis der Dual-Energy-Computertomografie (DECT) bei chronisch thromboembolischer pulmonaler Hypertonie (CTEPH). Fortschr Röntgenstr 2021; DOI: 10.1055/a-1502-7541.

Postpulmonary embolism syndrome

PURPOSE OF REVIEW

It is now recognized that more than half of patients with acute pulmonary embolism (APE) will have persistent symptoms beyond 3 months after their initial event. Persistent symptoms are referred to as post-PE syndrome, an umbrella term that covers a spectrum of patient complaints and underlying pathologies. Data published over the last 5 years have added significantly to our understanding of this syndrome and its management.

RECENT FINDINGS

Underlying pathologies linked to post-PE syndrome include chronic thromboembolic pulmonary hypertension (CTEPH), chronic thromboembolic disease (CTED), cardiac dysfunction, and deconditioning. Treatment for post-PE syndrome will depend on the underlying causative pathologies found. Evaluation and treatment for CTEPH is well defined, but less than 10% of patients with post-PE syndrome will qualify as having this diagnosis.

SUMMARY

A large percentage of patients will experience post-PE syndrome following APE. Strategies for identification and treatment for some pathologies are well studied, but the majority of patients will have subtle abnormalities on imaging and functional testing for which diagnostic criteria and management are not well defined. A number of active studies are designed to help optimize the management of post-PE syndrome and should help us improve intermediate and long-term outcomes for patients following APE.

Serum Liberation of Fetal Fibronectin Variants in Patients with Pulmonary Hypertension: ED-A+ Fn as Promising Novel Biomarker of Pulmonary Vascular and Right Ventricular Myocardial Remodeling

Background and Aims: Pulmonary Hypertension (PH) represents an aetiologically and clinically heterogeneous disorder accompanied by a severely impaired prognosis. Key steps of PH pathogenesis are vascular and right ventricular myocardial remodelling entailing the re-occurrence of fetal variants of the cell adhesion modulating protein fibronectin (Fn) being virtually absent in healthy adult tissues. These variants are liberated into circulation and are therefore qualified as excellent novel serum biomarkers. Moreover, these molecules might serve as promising therapeutic targets. The current study was aimed at quantifying the serum levels of two functionally important fetal Fn variants (ED-A⁺ and ED-B⁺ Fn) in patients suffering from PH due to different aetiologies compared to healthy controls. Methods: Serum levels of ED-A⁺ and ED-B⁺ Fn were quantified using novel ELISA protocols established and validated in our group in 80 PH patients and 40 controls. Results were analysed with respect to clinical, laboratory, echocardiographic and functional parameters. Results: Serum levels of ED-A⁺ Fn (p = 0.001) but not ED-B⁺ Fn (p = 0.722) were significantly increased in PH patients compared to healthy controls. Thus, the following analyses were performed only for ED-A⁺ Fn. When dividing PH patients into different aetiological groups according to current ESC guidelines, the increase in ED-A⁺ Fn in PH patients compared to controls remained significant for group 1 (p = 0.032), 2 (p = 0.007) and 3 (p = 0.001) but not for group 4 (p = 0.156). Correlation analysis revealed a significant relation between ED-A⁺ Fn and brain natriuretic peptide (BNP) (r = 0.310; p = 0.002), six minutes’ walk test (r = −0.275; p = 0.02) and systolic pulmonary artery pressure (PAPsys) (r = 0.364; p < 0.001). By logistic regression analysis (backward elimination WALD) including a variety of potentially relevant patients’ characteristics, only chronic kidney disease (CKD) (OR: 8.866; CI: 1.779–44.187; p = 0.008), C reactive protein (CRP) (OR: 1.194; CI: 1.011–1.410; p = 0.037) and ED-A⁺ Fn (OR: 1.045; CI: 1.011–1.080; p = 0.009) could be identified as independent predictors of the presence of PH. Conclusions: Against the background of our results, ED-A⁺ Fn could serve as a promising novel biomarker of PH with potential value for initial diagnosis and aetiological differentiation. Moreover, it might contribute to more precise risk stratification of PH patients. Beyond that, the future role of ED-A⁺ Fn as a therapeutic target has to be evaluated in further studies.

Chronic thromboembolic pulmonary hypertension risk score evaluation and validation (CTEPH Solution): proposal of a study protocol aimed to realize a validated risk score for early diagnosis

BACKGROUND

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is the most serious long-term complication of acute pulmonary embolism (PE) though it is the only potentially reversible form of Pulmonary Hypertension (PH). Its incidence is mainly limited to the first 2 years following the embolic event, however it is often underdiagnosed or misdiagnosed.

METHODS

This is a multicenter observational cross-sectional and prospective study. Patients with a prior diagnosis of PE will be enrolled and undergo baseline evaluation for prevalent PH detection through a clinical examination and an echocardiogram as first screening exam. All cases of intermediate-high echocardiographic probability of PH will be confirmed by right heart catheterization and then identified as CTEPH through appropriate imaging and functional examinations in order to exclude other causes of PH. A CTEPH Risk Score will be created using retrospective data from this prevalent cohort of patients and will be then validated on an incident cohort of patients with acute PE.

RESULTS

1000 retrospective and 218 prospective patients are expected to be enrolled and the study is expected to be completed by the end of 2021. Up to now 841 patients (620 retrospective and 221 prospective) have been enrolled.

CONCLUSIONS

This study is the first large prospective study for the prediction of CTEPH development in patients with PE. It aims to create a comprehensive scoring tool that includes echocardiographic data which may allow early detection of CTEPH and the application of targeted follow up screening programs in patients with PE.

Possible immune regulation mechanisms for the progression of chronic thromboembolic pulmonary hypertension

PURPOSE

This study aimed to screen key genes significantly associated with chronic thromboembolic pulmonary hypertension (CTEPH) and predicted suitable drugs for the treatment of CTEPH from the perspective of immune cells.

METHODS

The dataset GSE130391 was used for this analysis. Differentially expressed genes (DEGs) between the CTEPH and control groups were screened. Abundance of infiltrating immune cells was analyzed and immune-related DEGs were identified. Next, the circular RNA (circRNA)-micro RNA (miRNA)-mRNA network was constructed, followed by functional enrichment analysis. Then, the protein-protein interaction (PPI) network was constructed and drug-gene interactions were predicted. Finally, miRNA and circRNA prediction results were verified by our previously published studies.

RESULTS

Five key immune cell-related DEGs [CD83 molecule (CD83), complement c5a receptor 1 (C5AR1), atypical chemokine receptor 1 (ACKR1), profilin 2 (PFN2), and solute carrier family 2 member 3 (SLC2A3)] were identified. Several circRNA-miRNA-mRNA interactions were obtained, including circ_0022342miR-503-5pSLC2A3 and circ_0002062miR-92b-3p/miR-92a-3pmannosidase alpha class 2A member 1 (MAN2A1). Immune cell for SLC2A3 was eosinophils and for MAN2A1 was regulatory T cells (Tregs). Additionally, Glufosfamide and Kifunensine might be suitable as candidate drugs for CTEPH treatment.

CONCLUSIONS

SLC2A3 and MAN2A1 may be important genes for the pathogenesis of CTEPH. Possible immune regulation mechanisms in CTEPH may be circ_0022342miR-503-5pSLC2A3 and circ_0002062miR-92b-3p/miR-92a-3pMAN2A1. These results may be helpful for the diagnosis and treatment of CTEPH from the perspective of immunology.

Improved hemodynamics and cardiopulmonary function in patients with inoperable chronic thromboembolic pulmonary hypertension after balloon pulmonary angioplasty

Background

Balloon pulmonary angioplasty (BPA) has been demonstrated to improve cardiac function and exercise capacity in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH), but its instant impact on cardiopulmonary function has seldom been evaluated. This study aims to determine the safety and efficacy of BPA and its immediate and lasting effects on cardiopulmonary function among CTEPH patients.

Methods

From May 2018 to January 2019, patients with inoperable CTEPH who underwent BPA sessions were consecutively enrolled. Hemodynamics were measured by right heart catheterization, selective pulmonary angiography and BPA were successively conducted. Hemodynamic variables, WHO functional class (WHO-FC), 6-min walk distance (6MWD) and serum NT-proBNP were evaluated before and after BPA sessions during hospitalization. Pulmonary function testing (PFT) and cardiopulmonary exercise testing (CPET) were performed within 1–3 days pre and post BPA to evaluate the effect of BPA on cardiopulmonary function.

Results

Twenty-five patients with inoperable CTEPH who underwent a total of forty BPA sessions were consecutively enrolled. A total of 183 segmental or subsegmental vessels (4.6 ± 1.9 vessels per session) in 137 segments (3.4 ± 1.6 segments per session) were dilated. No procedure-related complications occurred. Instant hemodynamics, WHO-FC, 6MWD and NT-proBNP were all significantly improved after a single BPA session. Significant improvement in cardiopulmonary function was also evident as assessed by PFT indexes (forced vital capacity, forced expiratory volume in the first second, maximal voluntary ventilation) and CPET parameters (peak work rate, peak VO₂, oxygen uptake efficiency slope). Further analysis among ten CTEPH patients receiving multiple BPA sessions (2–4 sessions) indicated BPA resulted in lasting improvements in hemodynamics and cardiopulmonary function.

Conclusions

BPA, a safe and effective approach, can bring instant improvements after a single session and lasting benefits after multiple sessions to hemodynamics and cardiopulmonary function for patients with inoperable CTEPH.

Endocan as a marker of disease severity in pulmonary thromboembolism

INTRODUCTION

The aim of this study is to determine the serum endocan levels in patients with pulmonary thromboembolism (PTE) and investigate whether a relationship exists between serum endocan levels and the disease severity.

MATERIALS AND METHODS

The study included 85 patients with acute PTE and 40 healthy control subjects. The patients with PTE were divided into three groups at admission as "high-risk", "intermediate-risk" and "low-risk", considering the guidelines of the European Society of Cardiology. Serum endocan levels in all participants' blood samples were measured.

RESULTS

The mean serum endocan levels were significantly higher in the PTE group, compared to the control subjects (P < 0.001). Serum endocan levels were significantly higher in the "high-risk" group when compared with patients in the "low-risk" and "intermediate-risk" groups (P < 0.001 and P < 0.01 respectively). Similarly, serum endocan levels were higher in the "intermediate-risk" group compared to those in the "low-risk" group (P < 0.001). There was a negative correlation between serum endocan levels and partial oxygen pressure (r = -0.262, P = 0.016), whereas a positive correlation was found between the serum endocan levels and systolic pulmonary arterial pressure (r = 0.296, P = 0.006). Additionally, endocan had an area under the curve in the receiver operating characteristic curve of 0.837 (0.768-0.907; 95% CI; P < 0.001) and cut-off value was 194.5 pg/mL (sensitivity 80%, specificity 72.5%).

CONCLUSION

Serum endocan levels were higher and related to the severity of the disease in PTE patients. Additionally, endocan could be an indicator to be used in the diagnosis of PTE and in the prediction of the disease severity.

2018 TSOC guideline focused update on diagnosis and treatment of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized as a progressive and sustained increase in pulmonary vascular resistance, which may induce right ventricular failure. In 2014, the Working Group on Pulmonary Hypertension of the Taiwan Society of Cardiology (TSOC) conducted a review of data and developed a guideline for the management of PAH.⁴ In recent years, several advancements in diagnosis and treatment of PAH has occurred. Therefore, the Working Group on Pulmonary Hypertension of TSOC decided to come up with a focused update that addresses clinically important advances in PAH diagnosis and treatment. This 2018 focused update deals with: (1) the role of echocardiography in PAH; (2) new diagnostic algorithm for the evaluation of PAH; (3) comprehensive prognostic evaluation and risk assessment; (4) treatment goals and follow-up strategy; (5) updated PAH targeted therapy; (6) combination therapy and goal-orientated therapy; (7) updated treatment for PAH associated with congenital heart disease; (8) updated treatment for PAH associated with connective tissue disease; and (9) updated treatment for chronic thromboembolic pulmonary hypertension.

Clinical characteristics and prognosis in patients with chronic thromboembolic pulmonary hypertension and a concomitant psychiatric disorder

Chronic thromboembolic pulmonary hypertension (CTEPH) can cause right heart failure. A concomitant psychiatric disorder (PD) is thought to increase the risk of acute pulmonary thromboembolism; however, whether PDs are associated with deterioration in CTEPH pathophysiology is unclear. In this study, we evaluated the clinical characteristics and prognoses in patients with CTEPH and a co-existing PD. We retrospectively identified 229 consecutive patients (mean age = 58.7 ± 12.5 years; 160 women) with CTEPH and categorized them according to whether they had a PD (PD group; n = 22, 9.7%) or not (non-PD group; n = 207, 90.3%). We compared the clinical characteristics, respiratory function, hemodynamics, and clinical courses in the two groups. Those in the PD group had significantly lower exercise tolerance compared to the non-PD group (6-min walk test, 309.5 ± 89.5 m vs. 369.4 ± 97.9 m, P = 0.008, percent vital capacity 85.5% ± 17.3% vs. 96.0% ± 15.5%, P = 0.003) and partial pressure of oxygen (PaO2) (54.4 ± 8.6 mmHg vs. 59.3 ± 10.7 mmHg, P = 0.039). Three-year survival was significantly poorer in the PD group compared to the non-PD group (66.1% vs 89.7%, P = 0.0026, log-rank test), particularly in patients who underwent surgery (62.2% vs 89.5%, P < 0.001, log-rank test). A concomitant PD was associated with low exercise tolerance and impaired respiratory function in patients with CTEPH and predicted poor survival, especially in those who underwent a pulmonary endarterectomy.

Reoperative Pulmonary Endarterectomy: Past Failures of Patient Selection Can Assist in Future Practice of Informed Consent

The Pavia group reports their experience with reoperative pulmonary endarterectomy for patients with chronic thromboembolic pulmonary hypertension. They achieved impressive results in terms of hemodynamic parameters and functional status; however, a mortality rate of 40% represents inappropriate patient selection. Recommendations are made for identifying ideal operative candidates.