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.

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]. / 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).

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.

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.

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.

Fibroblast growth factor 23 as a biomarker of right ventricular dysfunction in pulmonary hypertension.

BACKGROUND: Fibroblast growth factor 23 (FGF-23) has been associated with left ventricular hypertrophy (LVH) and heart failure. However, its role in right ventricular (RV) remodeling and RV failure is unknown. This study analyzed the utility of FGF-23 as a biomarker of RV function in patients with pulmonary hypertension (PH). METHODS: In this observational study, FGF-23 was measured in the plasma of patients with PH (n = 627), dilated cardiomyopathy (DCM, n = 59), or LVH with severe aortic stenosis (n = 35). Participants without LV or RV abnormalities served as controls (n = 36). RESULTS: Median FGF-23 plasma levels were higher in PH patients than in healthy controls (p < 0.001). There were no significant differences between PH, DCM, and LVH patients. Analysis across tertiles of FGF-23 levels in PH patients revealed an association between higher FGF-23 levels and higher levels of NT-proBNP and worse renal function. Furthermore, patients in the high-FGF-23 tertile had a higher pulmonary vascular resistance (PVR), mean pulmonary artery pressure, and right atrial pressure and a lower cardiac index (CI) than patients in the low tertile (p < 0.001 for all comparisons). Higher FGF-23 levels were associated with higher RV end-diastolic diameter and lower tricuspid annular plane systolic excursions (TAPSE) and TAPSE/PASP. Receiver operating characteristic analysis revealed FGF-23 as a good predictor of RV maladaptation, defined as TAPSE < 17 mm and CI < 2.5 L/min/m2. Association of FGF-23 with parameters of RV function was independent of the glomerular filtration rate in regression analysis. CONCLUSION: FGF-23 may serve as a biomarker for maladaptive RV remodeling in patients with PH.

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.

Right Ventricular Strain by Magnetic Resonance Feature Tracking Is Largely Afterload-Dependent and Does Not Reflect Contractility: Validation by Combined Volumetry and Invasive Pressure Tracings.

Cardiac magnetic resonance (CMR) is currently the gold standard for evaluating right ventricular (RV) function, which is critical in patients with pulmonary hypertension. CMR feature-tracking (FT) strain analysis has emerged as a technique to detect subtle changes. However, the dependence of RV strain on load is still a matter of debate. The aim of this study was to measure the afterload dependence of RV strain and to correlate it with surrogate markers of contractility in a cohort of patients with chronic thromboembolic pulmonary hypertension (CTEPH) under two different loading conditions before and after pulmonary endarterectomy (PEA). Between 2009 and 2022, 496 patients with 601 CMR examinations were retrospectively identified from our CTEPH cohort, and the results of 194 examinations with right heart catheterization within 24 h were available. The CMR FT strain (longitudinal (GLS) and circumferential (GCS)) was computed on steady-state free precession (SSFP) cine CMR sequences. The effective pulmonary arterial elastance (Ea) and RV chamber elastance (Ees) were approximated by dividing mean pulmonary arterial pressure by the indexed stroke volume or end-systolic volume, respectively. GLS and GCS correlated significantly with Ea and Ees/Ea in the overall cohort and individually before and after PEA. There was no general correlation with Ees; however, under high afterload, before PEA, Ees correlated significantly. The results show that RV GLS and GCS are highly afterload-dependent and reflect ventriculoarterial coupling. Ees was significantly correlated with strain only under high loading conditions, which probably reflects contractile adaptation to pulsatile load rather than contractility in general.

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.

Chronic Lung Allograft Dysfunction Is Associated with Increased Levels of Cell-Free Mitochondrial DNA in Bronchoalveolar Lavage Fluid of Lung Transplant Recipients.

Chronic Lung Allograft Dysfunction (CLAD) is a life-threatening complication that limits the long-term survival of lung transplantation patients. Early diagnosis remains the basis of efficient management of CLAD, making the need for distinctive biomarkers critical. This explorative study aimed to investigate the predictive power of mitochondrial DNA (mtDNA) derived from bronchoalveolar lavages (BAL) to detect CLAD. The study included 106 lung transplant recipients and analyzed 286 BAL samples for cell count, cell differentiation, and inflammatory and mitochondrial biomarkers, including mtDNA. A receiver operating curve analysis of mtDNA levels was used to assess its ability to detect CLAD. The results revealed a discriminatory pro-inflammatory cytokine profile in the BAL fluid of CLAD patients. The concentration of mtDNA increased in step with each CLAD stage, reaching its highest concentration in stage 4, and correlated significantly with decreasing FEV1. The receiver operating curve analysis of mtDNA in BAL revealed a moderate prediction of CLAD when all stages were grouped together (AUROC 0.75, p-value < 0.0001). This study has found the concentration mtDNA in BAL to be a potential predictor for the early detection of CLAD and the differentiation of different CLAD stages, independent of the underlying pathology.

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.

Unmasking right ventricular-arterial uncoupling during fluid challenge in pulmonary hypertension.

BACKGROUND: Patients with pulmonary hypertension (PH) frequently show preserved right ventricular (RV) function at rest. However, volume challenge may uncover pending RV dysfunction. We aimed to assess the physiological and prognostic impact of RV-pulmonary arterial (RV-PA) uncoupling during volume challenge in patients with precapillary PH. METHODS: We prospectively assessed 32 patients with PH (pulmonary arterial hypertension, n = 27; inoperable chronic thromboembolic disease, n = 5) and 4 controls using invasive pressure-volume (PV) catheterization. PV loops were recorded during preload reduction (balloon occlusion of inferior vena cava; baseline) and acute volume loading (200 ml saline in 20 s). Contractility (multi-beat end-systolic elastance [Ees]), arterial elastance (Ea), and RV-PA coupling (Ees/Ea) were obtained at baseline and at maximum volume loading (MVL). RESULTS: Median [interquartile range] time to MVL was 19 [18-22] s. Ees/Ea significantly declined from baseline (0.89 [0.69-1.23]) to MVL (0.16 [0.12-0.34]; p < 0.001) in patients with PH but remained stable in controls (baseline: 1.08 [0.94-1.80]; MVL: 1.01 [0.80-2.49]; p = 0.715). The same pattern was observed for Ees, while Ea remained unchanged. The percent decline of RV-PA coupling (ΔEes/Ea) during fluid challenge was significantly associated with pulmonary resting hemodynamics, RV ejection fraction (RVEF), and RV end-diastolic volume. Kaplan-Meier analysis revealed that patients with PH who had a smaller ΔEes/Ea (<-65%) had a significantly better prognosis (log-rank p = 0.0389). In multivariate Cox regression analysis, clinical worsening was predicted by ΔEes/Ea (hazard ratio: 0.96 [95% confidence interval: 0.93-1.00]) and RVEF (hazard ratio: 0.95 [95% confidence interval: 0.92-0.98]). CONCLUSIONS: Assessment of PV loops during fluid challenge uncovers exhausted RV coupling reserve with severely reduced contractility in PH. RV-PA uncoupling during volume challenge can be predicted by pulmonary resting hemodynamics and RVEF. RV-PA uncoupling during fluid challenge and RVEF (as a noninvasive correlate) are predictors of clinical worsening. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03403868 (January 19, 2018).