Endothelial Overexpression of TGF-ß-Induced Protein Impairs Venous Thrombus Resolution: Possible Role in CTEPH.

Endothelial cells play a critical role during venous thrombus remodeling, and unresolved, fibrotic thrombi with irregular vessels obstruct the pulmonary artery in patients with chronic thromboembolic pulmonary hypertension (CTEPH). This study sought to identify endothelial mediators of impaired venous thrombus resolution and to determine their role in the pathogenesis of the vascular obstructions in patients with CTEPH. Endothelial cells outgrown from pulmonary endarterectomy specimens (PEA) were processed for mRNA profiling, and nCounter gene expression and immunohistochemistry analysis of PEA tissue microarrays and immunoassays of plasma were used to validate the expression in CTEPH. Lentiviral overexpression in human pulmonary artery endothelial cells (HPAECs) and exogenous administration of the recombinant protein into C57BL/6J mice after inferior Vena cava ligation were employed to assess their role for venous thrombus resolution. RT2 PCR profiler analysis demonstrated the significant overexpression of factors downstream of transforming growth factor beta (TGFß), that is TGFß-Induced Protein (TGFBI or BIGH3) and transgelin (TAGLN), or involved in TGFß signaling, that is follistatin-like 3 (FSTL3) and stanniocalcin-2 (STC2). Gene expression and immunohistochemistry analysis of tissue microarrays localized potential disease candidates to vessel-rich regions. Lentiviral overexpression of TGFBI in HPAECs increased fibrotic remodeling of human blood clots in vitro, and exogenous administration of recombinant TGFBI in mice delayed venous thrombus resolution. Significantly elevated plasma TGFBI levels were observed in patients with CTEPH and decreased after PEA. Our findings suggest that overexpression of TGFBI in endothelial promotes venous thrombus non-resolution and fibrosis and is causally involved in the pathophysiology of CTEPH.

[Chronic thromboembolic pulmonary hypertension]. / Chronisch thromboembolische pulmonale Hypertonie (Gruppe 4).

Chronic thromboembolic pulmonary disease (CTEPD) is an important late complication of acute pulmonary embolism, in which the thrombi transform into fibrous tissue, become integrated into the vessel wall, and lead to chronic obstructions. CTEPD is differentiated into cases without pulmonary hypertension (PH), characterized by a mean pulmonary arterial pressure up to 20 mmHg and a form with PH. Then, it is still referred to as chronic thromboembolic pulmonary hypertension (CTEPH).When there is suspicion of CTEPH, initial diagnostic tests should include echocardiography and ventilation/perfusion scan to detect perfusion defects. Subsequently, referral to a CTEPH center is recommended, where further imaging diagnostics and right heart catheterization are performed to determine the appropriate treatment.Currently, three treatment modalities are available. The treatment of choice is pulmonary endarterectomy (PEA). For non-operable patients or patients with residual PH after PEA, PH-targeted medical therapy, and the interventional procedure of balloon pulmonary angioplasty (BPA) are available. Increasingly, PEA, BPA, and pharmacological therapy are combined in multimodal concepts.Patients require post-treatment follow-up, preferably at (CTE)PH centers. These centers are required to perform a minimum number of PEA surgeries (50/year) and BPA interventions (100/year).

[Chronic thromboembolic pulmonary hypertension]. / Chronisch thromboembolische pulmonale Hypertonie.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease, but an important late sequela after acute pulmonary embolism. Therefore, follow-up after at least three months of sufficient anticoagulation is recommended. Patients with suspected CTEPH should be referred to specialized CTEPH centers for further evaluation and treatment.Three treatment modalities are available: pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA) and pulmonary hypertension-targeted drugs. The indication for surgery depends mainly on the localization of the pulmonary arterial obstructions. Severe comorbidities as well as advanced age need individual evaluation, but do not present strict exclusion criteria. Multimodal treatments are common practice in inoperable CTEPH. However, treatment decision making in an experienced multidisciplinary team is mandatory.

Chronic thromboembolic pulmonary hypertension: realising the potential of multimodal management.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism. Important advances have enabled better understanding, characterisation, and treatment of this condition. Guidelines recommending systematic follow-up after acute pulmonary embolism, and the insight that CTEPH can mimic acute pulmonary embolism on initial presentation, have led to the definition of CTEPH imaging characteristics, the introduction of artificial intelligence diagnosis pathways, and thus the prospect of easier and earlier CTEPH diagnosis. In this Series paper, we show how the understanding of CTEPH as a sequela of inflammatory thrombosis has driven successful multidisciplinary management that integrates surgical, interventional, and medical treatments. We provide imaging examples of classical major vessel targets, describe microvascular targets, define available tools, and depict an algorithm facilitating the initial treatment strategy in people with newly diagnosed CTEPH based on a multidisciplinary team discussion at a CTEPH centre. Further work is needed to optimise the use and combination of multimodal therapeutic options in CTEPH to improve long-term outcomes for patients.

Patient-Reported Long-Term Outcome of Balloon Pulmonary Angioplasty for Inoperable CTEPH.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is a promising interventional treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Evidence in favor of BPA is growing, but long-term data remain scarce. The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) is validated for the assessment of patients with pulmonary hypertension within three domains: symptoms, activity, and quality of life (QoL). The aim of the present study was to evaluate the long-term effects of BPA on these domains in patients with inoperable CTEPH. METHODS: Between March 2014 and August 2019, technically inoperable patients with target lesions for BPA were included in this prospective, observational study. CAMPHOR scores were compared between baseline (before the first BPA) and 6 months after the last intervention and also for scores assessed at annual follow-ups. RESULTS: A total of 152 patients had completed a full series of BPA interventions and a 28 (interquartile range [IQR]: 26-32) week follow-up. Further follow-up assessments including the CAMPHOR score were performed 96 (IQR: 70-117) weeks, 178 (IQR: 156-200) weeks, and 250 (IQR: 237-275) weeks after the last intervention. From baseline to the last follow-up, CAMPHOR scores for symptoms, activity, and QoL improved from 9 (IQR: 6-14) to 3 (IQR: 0-9) (p < 0.001), 8 (IQR: 5-12) to 4 (IQR: 2-8) (p < 0.001), and 5 (IQR: 2-9) to 1 (IQR: 0-5) (p < 0.001). CONCLUSION: BPA leads to long-lasting, significant improvement of symptoms, physical capacity, and QoL in inoperable CTEPH patients.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: a clinical consensus statement of the ESC working group on pulmonary circulation and right ventricular function.

The current treatment algorithm for chronic thromboembolic pulmonary hypertension (CTEPH) as depicted in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines on the diagnosis and treatment of pulmonary hypertension (PH) includes a multimodal approach of combinations of pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA) and medical therapies to target major vessel pulmonary vascular lesions, and microvasculopathy. Today, BPA of >1700 patients has been reported in the literature from centers in Asia, the US, and also Europe; many more patients have been treated outside literature reports. As BPA becomes part of routine care of patients with CTEPH, benchmarks for safe and effective care delivery become increasingly important. In light of this development, the ESC Working Group on Pulmonary Circulation and Right Ventricular Function has decided to publish a document that helps standardize BPA to meet the need of uniformity in patient selection, procedural planning, technical approach, materials and devices, treatment goals, complications including their management, and patient follow-up, thus complementing the guidelines. Delphi methodology was utilized for statements that were not evidence based. First, an anatomical nomenclature and a description of vascular lesions are provided. Second, treatment goals and definitions of complete BPA are outlined. Third, definitions of complications are presented which may be the basis for a standardized reporting in studies involving BPA. The document is intended to serve as a companion to the official ESC/ERS guidelines.

Evaluation of diagnostic accuracy of dual-energy computed tomography in patients with chronic thromboembolic pulmonary hypertension compared to V/Q-SPECT and pulmonary angiogram.

Purpose: The relevance of dual-energy computed tomography (DECT) for the detection of chronic thromboembolic pulmonary hypertension (CTEPH) still lies behind V/Q-SPECT in current clinical guidelines. Therefore, our study aimed to assess the diagnostic accuracy of DECT compared to V/Q-SPECT with invasive pulmonary angiogram (PA) serving as the reference standard. Methods: A total of 28 patients (mean age 62.1 years ± 10.6SD; 18 women) with clinically suspected CTEPH were retrospectively included. All patients received DECT with the calculation of iodine maps, V/Q-SPECT, and PA. Results of DECT and V/Q-SPECT were compared, and the percent of agreement, concordance (utilizing Cohen's kappa), and accuracy (kappa2) to PA were calculated. Furthermore, radiation doses were analyzed and compared. Results: In total, 18 patients were diagnosed with CTEPH (mean age 62.4 years ± 11.0SD; 10 women) and 10 patients had other diseases. Compared to PA, accuracy and concordance for DECT were superior to V/Q-SPECT in all patients (88.9% vs. 81.3%; k = 0.764 vs. k = 0.607) and in CTEPH patients (82.4% vs. 70.1%; k = 0.694 vs. k = 0.560). Furthermore, the mean radiation dose was significantly lower for DECT vs. V/Q-SPECT (p = 0.0081). Conclusion: In our patient cohort, DECT is at least equivalent to V/Q-SPECT in diagnosing CTEPH and has the added advantage of significantly lower radiation doses in combination with simultaneous assessment of lung and heart morphology. Hence, DECT should be the subject of ongoing research, and if our results are further confirmed, it should be implemented in future diagnostic PH algorithms at least on par with V/Q-SPECT.

Analysis of Electrocardiographic Criteria of Right Ventricular Hypertrophy in Patients with Chronic Thromboembolic Pulmonary Hypertension before and after Balloon Pulmonary Angioplasty.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) may lead to typical electrocardiographic changes that can be reversed by balloon pulmonary angioplasty (BPA). The aim of this study was to investigate the significance of rarely used electrocardiogram (ECG) parameters, possible electrocardiographic differences between residual and significantly improved CTEPH and the role of electrocardiographic parameters in low mPAP (mean pulmonary arterial pressure) ranges since the mPAP threshold for the definition of pulmonary hypertension has recently been adjusted (≥25 mmHg to >20 mmHg). MATERIAL AND METHODS: Between March 2014 and October 2020, 140 patients with CTEPH and 10 with CTEPD (chronic thromboembolic pulmonary disease) without pulmonary hypertension (PH) were retrospectively enrolled (12-lead ECG and right heart catheterization before and 6 months after BPA). The ECG parameters of right heart strain validated by studies and clinical experience were evaluated. Special attention was paid to six specific ECG parameters. After BPA, the cohort was divided into subgroups to investigate possible electrocardiographic differences with regard to the haemodynamic result. RESULTS: The present study confirmed that the typical electrocardiographic signs of CTEPH can be found on an ECG, can regress after BPA and partially correlate well with haemodynamic parameters. "R V1, V2 + S I, aVL - S V1" was a parameter of particular note. BPA reduced its frequency (47% vs. 29%) statistically significantly after Bonferroni correction (p < 0.001). Moreover, it showed a good correlation with mPAP and PVR (r-values: 0.372-0.519, p-values: < 0.001). Exceeding its cut-off value before therapy was associated with more severe CTEPH before therapy (higher mPAP, PVR, NT-pro-BNP and troponin and lower TAPSE) and an increased risk of death. Exceeding its cut-off value before and after therapy was associated with more severe CTEPH after therapy (higher RAP, mPAP, PVR, NT-pro-BNP and NYHA class) and an increased risk of death. Men tend to be affected more frequently. After subgrouping, it was observed that a higher median mPAP was associated with a higher right atrial pressure (RAP), a higher pulmonary vascular resistance (PVR) and a lower cardiac output (CO) before and after BPA. In addition, under these conditions, more and more severe electrocardiographic pathologies were detected before and after BPA. Some patients with low mPAP also continued to show mild ECG changes after BPA. In some cases, very few to no pathological ECG changes were detected, and the ECG could present as mostly normal in some patients (5% before BPA and 13% after BPA). CONCLUSION: "R V1, V2 + S I, aVL - S V1" seems to be able to support the diagnosis of CTEPH, indicate therapeutic improvement and estimate haemodynamics. It also seems capable of predicting a (persistent) severe disease with probably increased need for therapy and increased mortality. Mild PH has been observed to have either no or few mild ECG changes. This might complicate the (early) detection of PH.

3D Visualization, Skeletonization and Branching Analysis of Blood Vessels in Angiogenesis.

Angiogenesis is the process of new blood vessels growing from existing vasculature. Visualizing them as a three-dimensional (3D) model is a challenging, yet relevant, task as it would be of great help to researchers, pathologists, and medical doctors. A branching analysis on the 3D model would further facilitate research and diagnostic purposes. In this paper, a pipeline of vision algorithms is elaborated to visualize and analyze blood vessels in 3D from formalin-fixed paraffin-embedded (FFPE) granulation tissue sections with two different staining methods. First, a U-net neural network is used to segment blood vessels from the tissues. Second, image registration is used to align the consecutive images. Coarse registration using an image-intensity optimization technique, followed by finetuning using a neural network based on Spatial Transformers, results in an excellent alignment of images. Lastly, the corresponding segmented masks depicting the blood vessels are aligned and interpolated using the results of the image registration, resulting in a visualized 3D model. Additionally, a skeletonization algorithm is used to analyze the branching characteristics of the 3D vascular model. In summary, computer vision and deep learning is used to reconstruct, visualize and analyze a 3D vascular model from a set of parallel tissue samples. Our technique opens innovative perspectives in the pathophysiological understanding of vascular morphogenesis under different pathophysiological conditions and its potential diagnostic role.

Chronic thromboembolic pulmonary hypertension-medical, interventional, and surgical therapy.

Chronic thromboembolic pulmonary hypertension (CTEPH) is an important late sequela of pulmonary embolism and a common form of pulmonary hypertension. Currently, three specific treatment modalities are available: pulmonary endarterectomy, balloon pulmonary angioplasty, and targeted medical therapy. The treatment decision depends mainly on the exact localization of the underlying pulmonary arterial obstructions. Pulmonary endarterectomy is the gold standard treatment of CTEPH. For inoperable patients, riociguat and treprostinil are approved. In addition, interventional therapy is recommended if appropriate target lesions are proven. Evaluation and treatment of patients with CTEPH in experienced centers are mandatory.

Value of Right and Left Ventricular T1 and T2 Blood Pool Mapping in Patients with Chronic Thromboembolic Hypertension before and after Balloon Pulmonary Angioplasty.

BACKGROUND: Parametric imaging has taken a steep rise in recent years and non-cardiac applications are of increasing interest. Therefore, the aim of our study was to assess right (RV) and left ventricular (LV) blood pool T1 and T2 values in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to control subjects and their correlation to pulmonary hemodynamic. METHODS: 26 patients with CTEPH (mean age 64.8 years ± 12.8 SD; 15 female), who underwent CMR and right heart catheterization (RHC) before and 6-months after balloon pulmonary angioplasty (BPA), were retrospectively included. Ventricular blood pool values were measured, compared to control subjects (mean age 40.5 years ± 12.8 SD; 16 female) and correlated to invasive measures (CI, mPAP, PVR). RESULTS: In both, control subjects and CTEPH patients, RVT1 and RVT2 were significantly reduced compared to LVT1 and LVT2. Compared to control subjects, RVT2 was significantly reduced in CTEPH patients (p = 0.0065) and increased significantly after BPA (p = 0.0048). Moreover, RVT2 was positively correlated with CI and negatively correlated with mPAP and PVR before (r = 0.5155, r = -0.2541, r = -0.4571) and after BPA (r = 0.4769, r = -0.2585, r = -0.4396). CONCLUSION: Ventricular blood pool T2 mapping might be novel non-invasive CMR imaging marker for assessment of disease severity, prognosis, follow-up and even therapy monitoring in PH.

Highlights from the International Chronic Thromboembolic Pulmonary Hypertension Congress 2021.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism. It is caused by persistent obstruction of pulmonary arteries by chronic organised fibrotic clots, despite adequate anticoagulation. The pulmonary hypertension is also caused by concomitant microvasculopathy which may progress without timely treatment. Timely and accurate diagnosis requires the combination of imaging and haemodynamic assessment. Optimal therapy should be individualised to each case and determined by an experienced multidisciplinary CTEPH team with the ability to offer all current treatment modalities. This report summarises current knowledge and presents key messages from the International CTEPH Conference, Bad Nauheim, Germany, 2021. Sessions were dedicated to 1) disease definition; 2) pathophysiology, including the impact of the hypertrophied bronchial circulation, right ventricle (dys)function, genetics and inflammation; 3) diagnosis, early after acute pulmonary embolism, using computed tomography and perfusion techniques, and supporting the selection of appropriate therapies; 4) surgical treatment, pulmonary endarterectomy for proximal and distal disease, and peri-operative management; 5) percutaneous approach or balloon pulmonary angioplasty, techniques and complications; and 6) medical treatment, including anticoagulation and pulmonary hypertension drugs, and in combination with interventional treatments. Chronic thromboembolic pulmonary disease without pulmonary hypertension is also discussed in terms of its diagnostic and therapeutic aspects.

Riociguat and balloon pulmonary angioplasty improve prognosis in patients with inoperable chronic thromboembolic pulmonary Hypertension.

BACKGROUND: The combination of riociguat and interventional balloon pulmonary angioplasty (BPA) is currently used to treat patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). The aim of the present study was to evaluate the impact of this combination therapy on the prognosis of inoperable CTEPH patients by comparing the long-term survival rates of patients undergoing combination therapy with riociguat and BPA with those of inoperable patients from the first international CTEPH registry who did not receive specific treatment. METHODS: Between March 2014 and August 2019, 138 technically inoperable patients were included in the present prospective, observational cohort study when they were treated with riociguat and BPA at a single CTEPH referral center. Long-term survival of this cohort was compared using propensity score matching with that of inoperable patients recruited between 2007 and 2009 in the first international CTEPH registry. Kaplan-Meier methods were used to evaluate differences in outcomes. RESULTS: Whereas the survival rate in the historical group was 84.6% in the first year, 76.6% in the second, 68.5% in the third, and 58.5% in the fifth year after diagnosis, implementation of riociguat/BPA led to survival rates of 100%, 96.7%, 92.9%, and 90% in the respective follow-up periods. In a comparison of 83 well-matched pairs from the 2 cohorts, survival was markedly better in the group treated with riociguat and BPA than in the historical cohort (HR = 0.145, 95% CI 0.05, 0.421). CONCLUSION: The combination of riociguat and BPA for the treatment of inoperable CTEPH is associated with excellent 5-year survival rates.

Exercise MR-proANP unmasks latent right heart failure in CTEPH.

OBJECTIVE: The present study was designed to investigate the dynamics of right atrial pressure (RAP) and mid-regional pro-atrial natriuretic peptide (MR-proANP) during physical exercise in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and to determine whether these parameters might serve as a tool to measure exercise-dependent atrial stress as an indicator of right heart failure. METHODS: This prospective observational cohort study included 100 CTEPH patients who underwent right heart catheterization during physical exercise (eRHC). Blood samples for MR-proANP measurement were taken prior, during, and after eRHC. MR-proANP levels were correlated to RAP levels at rest, at peak exercise (eRAP), and during recovery. RAP at rest ≤7 mmHg was defined as normal and eRAP >15 mmHg as suggestive of right heart failure. RESULTS: During eRHC mean RAP increased from 6 mmHg (standard deviation, SD 4) to 16 mmHg (SD 7; p < 0.001). MR-proANP levels and dynamics correlated with RAP at rest (rs = 0.61; p < 0.001) and at peak exercise (rs = 0.66; p < 0.001). Logistic regression analysis revealed the peak MR-proANP level (B = 0.058; p = 0.004) and the right atrial area (B = 0.389; p < 0.001) to be associated with eRAP dynamics. A peak MR-proANP level ≥139 pmol/L (AUC = 0.81) and recovery level ≥159 pmol/L (AUC = 0.82) predicted an eRAP >15 mmHg. Physical exercise unmasked right heart failure in 39% of patients with normal RAP at rest; these patients were also characterized by a more distinct increase in MR-proANP levels (p = 0.005) and higher peak (p < 0.001) and recovery levels (p < 0.001). CONCLUSIONS: RAP and MR-proANP dynamics unmask manifest and latent right heart failure in CTEPH patients.

Complications of balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension: Impact on the outcome.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is an emerging interventional treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) that targets subsegmental branches of the pulmonary artery. As the reported complication rates are high, the aim of the present study was to evaluate the effects of certain complications on the outcome after treatment. METHODS: From March 2014 to December 2019, a total of 235 patients with inoperable CTEPH underwent BPA. Of these patients, 140 were included who completed a follow-up examination 6 months after the last intervention; another 2 patients deceased due to complications of BPA. RESULTS: A high baseline pulmonary vascular resistance (PVR) >6.6 WU correlated with a higher rate of complications (mostly pulmonary artery perforations). Wire perforation during BPA did not correlate with worse outcome in terms of PVR reduction. The complication rate per intervention decreased from 21% to 14% during the 5 year period of the study. CONCLUSIONS: Complications are frequently observed in BPA, but the mortality rate is very low in expert centers. Importantly, the occurrence of complications does not portend a worse outcome.

Pulmonary endarterectomy: technique and pitfalls.

Chronic thromboembolic pulmonary hypertension (CTEPH) remains a rare and underdiagnosed disease. After one or several episodes of acute pulmonary embolism, around 3% of patients develop CTEPH and two-thirds of these patients are potential surgical candidates. Besides surgery, additional treatment modalities are pulmonary arterial hypertension medication and balloon pulmonary angioplasty. Patients should be evaluated in CTEPH expert centers to ensure the most appropriate therapy. Pulmonary endarterectomy (PEA) is a complex, but standardized surgical procedure aiming to clear the obstructed pulmonary arteries completely. For optimal visualization, deep hypothermic circulatory arrest is a prerequisite. This article will give an overview of the evaluation, indication and surgical management of patients with CTEPH.

Does Age Matter? Pulmonary Endarterectomy in the Elderly Patient with CTEPH.

BACKGROUND: The gold standard treatment of patients with chronic thromboembolic pulmonary hypertension (CTEPH) is pulmonary endarterectomy (PEA). Little is known about the influence of advanced age on surgical outcome. Therefore, the aim of this study was to investigate the impact of patient's age on postoperative morbidity, mortality, and quality of life in a German referral center. METHODS: Prospectively collected data from 386 consecutive patients undergoing PEA between 01/2014 and 12/2016 were analyzed. Patients were divided into three groups according to their age: group 1: ≤ 50 years, group 2: > 50 ≤ 70 years, group 3: > 70 years. RESULTS: After PEA, distinct improvements in pulmonary hemodynamics, physical capacity (World Health Organization [WHO] functional class and 6-minute walking distance) and quality of life were found in all groups. There were more complications in elderly patients with longer time of invasive ventilation, intensive care, and in-hospital stay. However, the in-hospital mortality was comparable (0% in group 1, 2.6% in group 2, and 2.1% in group 3 [p = 0.326]). Furthermore, the all-cause mortality at 1 year was 1.1% in group 1, 3.2% in group 2, and 6.3% in group 3 (p = 0.122). CONCLUSIONS: PEA is an effective treatment for CTEPH patients of all ages accompanied by low perioperative and 1-year mortality. CTEPH patients in advanced age carefully selected by thorough preoperative evaluation should be offered PEA in expert centers to improve quality of life, symptoms, and pulmonary hemodynamics.