Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

Balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension: a multicentre registry

BACKGROUND

Balloon pulmonary angioplasty (BPA) is a promising therapy for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are ineligible for pulmonary endarterectomy.

AIMS

The present study aimed to evaluate the safety and efficacy of BPA for CTEPH using the first multicentre registry of a single European country.

METHODS

Data were obtained from the Database of Pulmonary Hypertension in the Polish Population (NCT03959748), a prospective, multicentre registry of adult and paediatric pulmonary arterial hypertension (PAH) and CTEPH, for a total of 236 patients with confirmed CTEPH (124 women; mean age 67 years) who underwent 1,056 BPA procedures at eight institutions in Poland.

RESULTS

In 156 patients who underwent follow-up assessments after a median of 5.9 (IQR: 3.0-8.0) months after final BPA, the mean pulmonary arterial pressure decreased from 45.1±10.7 to 30.2±10.2 mmHg (p<0.001) and pulmonary vascular resistance from 642±341 to 324±183 dynes (p<0.001), and the six-minute walking test (6MWT) improved from 341±129 to 423±136 m (p<0.001). Pulmonary injury related to the BPA procedure occurred in 6.4% of all sessions. Eighteen patients (7.6%) died during follow-up, including 4 (1.7%) who died within 30 days after BPA. Overall survival was 92.4% (95% confidence interval [CI]: 87.6%-94.9%) three years after the initial BPA procedure.

CONCLUSIONS

This multicentre registry confirmed significant improvement of haemodynamic, functional, and biochemical parameters after BPA. Complication rates were low and overall survival comparable to the results of another registry. Therefore, BPA may be an important therapeutic option in patients with CTEPH in Poland.

Association of Electrocardiographic Signs of Right Ventricular Hypertrophy and Clot Localization in Chronic Thromboembolic Pulmonary Hypertension

The role of electrocardiography (ECG) in chronic thromboembolic pulmonary hypertension (CTEPH) diagnosis and prognosticating has not been yet established. We aimed to assess the relationships of the recommended ECG criteria of right ventricular hypertrophy (RVH) with clot localization in CTEPH patients. ECG patterns of RVH according to the American College of Cardiology Foundation were assessed in patients with newly diagnosed CTEPH. We enrolled 58 (45.3%) patients with proximal and 70 (54.7%) with distal CTEPH. Receiver-operating characteristics curves analysis indicated that the following ECG abnormalities predicted proximal CTEPH localization: R_V1 > 6 mm—AUC 0.75 (CI: 0.66–0.84, p < 0.00001); S_V6 > 3 mm—AUC 0.70 (CI: 0.60–0.79, p < 0.00001); S_I > R_I wave—AUC 0.67 (CI: 0.58–0.77, p = 0.0004); R_V1:S_V1 > 1.0—AUC 0.66 (CI: 0.56–0.76, p = 0.0009); R_V1 peak > 0.035 s (QRS < 120 ms)—AUC 0.66 (CI: 0.56–0.75, p = 0.0016); R_V1:S_V1 > R_V3(V4):S_V3(V4)—AUC-0.65 (CI: 0.54–0.75, p = 0.0081); R_aVR > 4 mm—AUC 0.62 (CI: 0.52–0.71, p = 0.002) and P_II > 2.5 mm—AUC 0.62 (CI: 0.52–0.72, p = 0.00162). Pulmonary vascular resistance significantly correlated with amplitudes of R_V1 (r = 0.34, p = 0.008), S_V6 (r = 0.53, p = 0.000027) and P_II (r = 0.44, p = 0.00007). In patients with CTEPH, only 8 out of 23 ECG RVH criteria were useful for differentiating between proximal and distal CTEPH localization and we found that R_V1 and S_V6 may contribute as potential discriminators.

Epigenetic Modification of the VWF Promotor Drives Platelet Aggregation on the Pulmonary Endothelium in Chronic Thromboembolic Pulmonary Hypertension

RATIONALE

Von Willebrand Factor (VWF) mediates platelet adhesion during thrombosis. While chronic thromboembolic pulmonary hypertension (CTEPH) is associated with increased plasma levels of VWF, the role of this protein in CTEPH has remained enigmatic.

OBJECTIVE

To identify the role of VWF in CTEPH.

METHODS

CTEPH-specific patient plasma and pulmonary endarterectomy material from CTEPH patients were used to study the relationship between inflammation, VWF expression and pulmonary thrombosis. Cell culture findings were validated in human tissue and proteomics and chromatin immunoprecipitation were used to investigate the underlying mechanism of CTEPH.

MEASUREMENTS AND MAIN RESULTS

VWF is increased in plasma and in the pulmonary endothelium of CTEPH patients. In vitro, the increase in VWF gene expression and the higher release of VWF protein upon endothelial activation resulted in elevated platelet adhesion to CTEPH endothelium. Proteomic analysis revealed that Nuclear Factor κB 2 (NFκB2) was significantly increased in CTEPH. We demonstrate reduced histone tri-methylation and increased histone acetylation of the VWF promotor in CTEPH endothelium, facilitating binding of NFκB2 to the VWF promotor and driving VWF transcription. Genetic interference of NFκB2 normalized the high VWF RNA expression levels and reversed the pro-thrombotic phenotype observed in CTEPH-PAEC.

CONCLUSION

Epigenetic regulation of the VWF promotor contributes to the creation of a local environment that favors in situ thrombosis in the pulmonary arteries. It reveals a direct molecular link between inflammatory pathways and platelet adhesion in the pulmonary vascular wall, emphasizing a possible role of in situ thrombosis in the development or progression of CTEPH.

Initiating a Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy Program Based on a Single Center Experience in Lebanon

Purpose

In 2018, the American University of Beirut Medical Center established the first multidisciplinary Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy program in Lebanon. The study describes the challenges faced in establishing the program and in improving patient referral, evaluation, and perioperative care.

Methods

The program establishment including the preparation phase, clinical evaluation, and team education is discussed. The implementation of the flow of patients referred to the program was established. Education regarding diagnosis and referral were provided to physicians in the community. The initial experience is described in a retrospective analysis of 4 consecutive patients who were diagnosed with CTEPH and underwent PEA.

Results

Four patients were diagnosed with CTEPH had PEA performed. The mean age of patients was 64 years. The average CPB and total circulatory arrest times were 244 and 23.9 minutes per side, respectively. No mortalities were encountered perio-operatively. All patients reported significant improvement in functional capacity from NYHA III and IV to a NYHA class of I with an average PASP decrease of 59.5 ± 19.7 mmHg and mPAP drop by 30.2 ± 16.3 mmHg.

Conclusion

The launch of the first CTEPH and PEA program in Lebanon, with a clear framework, coupled with good surgical outcomes is very encouraging. The program offers a curative solution for CTEPH patients in the region. A clear referral process and an increase in disease and treatment awareness in the community are crucial to the future success of the program, offering a definitive treatment, and avoiding delays to surgery.

Post severe COVID-19 infection lung damages study. The experience of early three months multidisciplinary follow-up

The correct type and time of follow-up for patients affected by COVID19 ARDS is still unclear. The aim of this study was to evaluate at the survivors to COVID19 ARDS requiring non-invasive respiratory support (NRS) admitted to a Respiratory Intensive care unit (RICU) from March 8th till May 31th 2020 looking at all sequelae via a comprehensive follow up. All patients underwent a multi-disciplinary instrumental and clinical assessment within three months form admission to evaluate all infection related sequelae. Thirty-eight patients were enrolled Lung-Ultrasound (LUS) showed an outstanding discrimination ability (ROC AUC: 0.95) and a substantial agreement rate (Cohen's K: 0.74) compared to chest CT-scan detecting improvement of lung consolidations. Youden's test showed a cut-off pressure of 11 cmH2O ExpiratoryPAP-Continuous-PAP-max (EPAP-CPAP) applied at the airways during hospitalization to be significantly correlated (p value: 0.026) to the increased pulmonary artery common trunk diameter. A total of 8/38 patients (21.8%), 2 of whom during follow-up, were diagnosed with Pulmonary Emboli (PE) and started anticoagulant treatment. Patients with PE had a statistically significant shorter length of time of hospitalization, time to negative swab, CPAP/NIV duration, P/F ratio and D-dimers at follow-up compared to non PE. A comprehensive approach to patients with ARDS COVID19 requiring NRS is necessary. This study highlighted cardiopulmonary impairment related to the ARDS and to the high-EPAP-CPAP-max greater than 11mmHg provided during admission, the usefulness of LUS in monitoring post-infection recovery and the correct identification and  treatment of patients with PE during follow up.

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.

Epidemiology of chronic thromboembolic pulmonary hypertension (CTEPH) in the Czech Republic

This study investigated the epidemiology and survival outcomes of chronic thromboembolic pulmonary hypertension (CTEPH) in the Czech Republic, wherein pulmonary endarterectomy (PEA) surgery was the only targeted treatment option until 2015. This study included all consecutive adults newly diagnosed with CTEPH in the Czech Republic between 2003 and 2016. Incidence/prevalence rates were calculated using general population data extracted from the Institute of Health Information and Statistics of the Czech Republic. Kaplan–Meier estimates of survival from diagnosis until 2018 were calculated. Of a total of 453 patients observed, 236 (52.1%) underwent PEA (median time from diagnosis to PEA: 2.9 months) and 71 (34.1%) had residual pulmonary hypertension (PH) post‐PEA. CTEPH incidence rate (95% confidence interval [CI]) between 2006 and 2016 was 4.47 (4.05; 4.91) patients per million (ppm) per year, and the prevalence (95% CI) was 37.43 (33.46; 41.73) ppm in 2016. The rate of CTEPH‐related hospitalizations (95% CI) per 100 person‐years was 24.4 (22.1; 26.9) for operated patients and 34.2 (30.9; 37.7) for not‐operated patients. Median overall survival (95% CI) for all patients from CTEPH diagnosis was 11.2 (9.4; not reached) years. Five‐year survival probability (95% CI) was 95.3% (89.9; 97.9) for operated patients without residual PH, 86.3% (75.3; 92.7) for operated patients with residual PH and 61.2% (54.0; 67.6) for not‐operated patients. This study reported epidemiological estimates of CTEPH in the Czech Republic consistent with estimates from other national systematic registries; and indicates an unmet medical need in not‐operated patients and operated patients with residual PH.

The Roles of S100A4 and the EGF/EGFR Signaling Axis in Pulmonary Hypertension with Right Ventricular Hypertrophy

Pulmonary hypertension (PH) is characterized by increased pulmonary arterial pressure caused by the accumulation of mesenchymal-like cells in the pulmonary vasculature. PH can lead to right ventricular hypertrophy (RVH) and, ultimately, heart failure and death. In PH etiology, endothelial-to-mesenchymal transition (EndMT) has emerged as a critical process governing the conversion of endothelial cells into mesenchymal cells, and S100A4, EGF, and EGFR are implicated in EndMT. However, a potential role of S100A4, EGF, and EGFR in PH has to date not been elucidated. We therefore quantified S100A4, EGF, and EGFR in patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH) and idiopathic pulmonary arterial hypertension (iPAH). To determine specificity for unilateral heart disease, the EndMT biomarker signature was further compared between PH patients presenting with RVH and patients suffering from aortic valve stenosis (AVS) with left ventricular hypertrophy. Reduced S100A4 concentrations were found in CTEPH and iPAH patients with RVH. Systemic EGF was increased in CTEPH but not in iPAH, while AVS patients displayed slightly diminished EGF levels. EGFR was downregulated in all patient groups when compared to healthy controls. Longitudinal data analysis revealed no effect of surgical therapies on EndMT markers. Pulmonary thrombo-endarterectomized samples were devoid of S100A4, while S100A4 tissue expression positively correlated with higher grades of Heath–Edwards histopathological lesions of iPAH-derived lung tissue. Histologically, EGFR was not detectable in CTEPH lungs or in iPAH lesions. Together, our data suggest an intricate role for S100A4 and EGF/EGFR in PH with right heart pathology.

Frequency of Thrombotic Risk Factors in Patients with Chronic Thromboembolic Pulmonary Hypertension and Acute Pulmonary Embolism: A Case-Control Study

Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious complication of acute pulmonary embolism (PE) which remains underdiagnosed. A better understanding of risk factors for CTEPH would improve our ability to predict which PE survivors are at risk. Several medical conditions-including malignancy, splenectomy, thyroid hormone supplementation, the presence of an intravascular device, inflammatory bowel disease, osteomyelitis, and non-O blood group-have been associated with increased risk of CTEPH, primarily in studies comparing patients with CTEPH to individuals with non-thrombotic conditions. Because many of these conditions increase thrombosis risk, it remains unclear whether their association with CTEPH reflects a general effect on thrombosis risk, or a specific effect on the risk of developing CTEPH as an outcome of thrombosis. We performed a case-control study comparing the frequencies of these conditions in patients with CTEPH versus patients with acute PE who did not develop CTEPH. The conditions studied were equally frequent in the CTEPH and PE cohorts, although there was a trend towards an increased frequency of splenectomy and non-O blood group among the CTEPH cohort. Thus, other than the possible exceptions of splenectomy and non-O blood group, the investigated medical conditions do not appear likely to increase the risk of CTEPH as an outcome of acute PE, and thus are unlikely to be useful in predicting CTEPH risk among PE survivors.

Impact and safety of balloon pulmonary angioplasty for elderly patients

Recently, balloon pulmonary angioplasty (BPA) for chronic thromboembolic pulmonary hypertension (CTEPH) and chronic thromboembolic pulmonary disease (CTEPD) has become an established procedure with stable results. The number of elderly CTEPH/CTEPD patients has also increased due to the widespread recognition of the disease concept. However, the reports of BPA in the elderly are limited. The aim of this study was to evaluate the efficacy and safety of BPA in elderly patients (>80 years). From April 2016 to December 2020, 344 BPA sessions (74 patients) were performed. The safety and efficacy of the BPA procedures were compared in the younger group (<80 years; 278 sessions) and the elderly group (≥80 years; 66 sessions). The hemodynamic parameters were significantly improved in both groups (mean pulmonary arterial pressure: 34.4 ± 9.9 → 21.2 ± 6.2 mmHg, p < 0.001 and 33.2 ± 9.6 → 21.8 ± 8.5 mmHg, p < 0.001; pulmonary vascular resistance: 474.5 ± 248.6 → 201.3 ± 108.7 dyne sec cm⁻⁵, p < 0.001 and 496.4 ± 290.9 → 260.5 ± 120.2 dyne sec cm⁻⁵, p = 0.002, in younger and elderly group, respectively). The rate of death within 30 days of BPA (0.3% vs. 0%, p = 1.000) and use of positive pressure ventilation (1.4% vs. 3.0%, p = 0.600) were not different between the groups (younger vs. elderly, respectively). BPA significantly improved the hemodynamic parameters of elderly CTEPH/CTEPD patients, and the safety is comparable to that of younger patients.

Modulation of soluble guanylate cyclase ameliorates pulmonary hypertension in a rat model of chronic thromboembolic pulmonary hypertension by stimulating angiogenesis

Acute pulmonary embolism (PE) does not always resolve after treatment and can progress to chronic thromboembolic disease (CTED) or the more severe chronic thromboembolic pulmonary hypertension (CTEPH). The mechanisms surrounding the likelihood of PE resolution or progress to CTED/CTEPH remain largely unknown. We have developed a rat model of CTEPH that closely resembles the human disease in terms of hemodynamics and cardiac manifestations. Embolization of rats with polystyrene microspheres followed by suppression of angiogenesis with the inhibitor of vascular endothelial growth factor receptor 2 (VEGF-R2) SU5416 results in transient, acute pulmonary hypertension that progresses into chronic PE with PH with sustained right ventricular systolic pressures exceeding 70 mmHg (chronic pulmonary embolism [CPE] model). This model is similar to the widely utilized hypoxia/SU5416 model with the exception that the "first hit" is PE. Rats with CPE have impaired right heart function characterized by reduced VO2 Max, reduced cardiac output, and increased Fulton index. None of these metrics are adversely affected by PE alone. Contrast-mediated CT imaging of lungs from rats with PE minus SU5416 show large increases in pulmonary vascular volume, presumably due to an angiogenic response to acute PE/PH. Co-treatment with SU5416 suppresses angiogenesis and produces the CTEPH-like phenotype. We report here that treatment of CPE rats with agonists for soluble guanylate cyclase, a source of cGMP which is in turn a signal for angiogenesis, markedly increases angiogenesis in lungs, and ameliorates the cardiac deficiencies in the CPE model. These results have implications for future development of therapies for human CTEPH.

CMR Measures of Left Atrial Volume Index and Right Ventricular Function Have Prognostic Value in Chronic Thromboembolic Pulmonary Hypertension

Providing prognostic information is important when counseling patients and planning treatment strategies in chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this study was to assess the prognostic value of gold standard imaging of cardiac structure and function using cardiac magnetic resonance imaging (CMR) in CTEPH. Consecutive treatment-naive patients with CTEPH who underwent right heart catheterization and CMR between 2011 and 2017 were identified from the ASPIRE (Assessing-the-Specturm-of-Pulmonary-hypertensIon-at-a-REferral-center) registry. CMR metrics were corrected for age and sex where appropriate. Univariate and multivariate regression models were generated to assess the prognostic ability of CMR metrics in CTEPH. Three hundred and seventy-five patients (mean+/-standard deviation: age 64+/-14 years, 49% female) were identified and 181 (48%) had pulmonary endarterectomy (PEA). For all patients with CTEPH, left-ventricular-stroke-volume-index-%predicted (LVSVI%predicted) (p = 0.040), left-atrial-volume-index (LAVI) (p = 0.030), the presence of comorbidities, incremental shuttle walking test distance (ISWD), mixed venous oxygen saturation and undergoing PEA were independent predictors of mortality at multivariate analysis. In patients undergoing PEA, LAVI (p < 0.010), ISWD and comorbidities and in patients not undergoing surgery, right-ventricular-ejection-fraction-%predicted (RVEF%pred) (p = 0.040), age and ISWD were independent predictors of mortality. CMR metrics reflecting cardiac function and left heart disease have prognostic value in CTEPH. In those undergoing PEA, LAVI predicts outcome whereas in patients not undergoing PEA RVEF%pred predicts outcome. This study highlights the prognostic value of imaging cardiac structure and function in CTEPH and the importance of considering left heart disease in patients considered for PEA.

Predictors of early response to balloon pulmonary angioplasty in patients with inoperable chronic thromboembolic pulmonary hypertension

Background:

To achieve favorable hemodynamics, the number of balloon pulmonary angioplasty (BPA) sessions varied significantly among patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Increased BPA sessions burdened patients financially and psychologically. We aim to identify baseline characteristics that could predict early BPA response.

Methods:

Consecutive patients who were diagnosed with inoperable CTEPH and received BPA between May 2018 and October 2021 at Fuwai Hospital were retrospectively collected. Patients were categorized into ‘Early BPA responders’ or ‘Non-early BPA responders’ according to the hemodynamic outcome within the first three BPA sessions.

Results:

In total, 101 patients were included into analysis. At baseline, non-early BPA responders had lower female proportion, longer disease duration, and poorer laboratory test results compared with early responders, whereas hemodynamics were comparable. After the first three BPA sessions, hemodynamic improvement was more significant in early responders. Incidence of complication was comparable between the two groups. Multivariable logistic analysis identified that female sex (odds ratio [OR]: 7.155, 95% confidence interval [CI]: 1.323-38.692, p = 0.022), disease duration (OR: 0.851, 95% CI: 0.727-0.995, p = 0.043), baseline total bilirubin (OR: 0.934, 95% CI: 0.875-0.996, p = 0.038), and baseline NT-proBNP (OR: 0.473, 95% CI: 0.255-0.879, p = 0.018) were independently associated with early BPA response. Combination of these four parameters could predict 90% early BPA response.

Conclusions:

Patients with shorter disease duration, female sex, lower baseline NT-proBNP, and lower baseline total bilirubin are more likely to achieve early hemodynamic response to BPA. Moreover, early hemodynamic response was not accompanied with increased incidence of procedure-related complications.

Balloon pulmonary angioplasty combined with riociguat for the treatment of inoperable chronic thromboembolic pulmonary hypertension (PRACTICE study): study protocol for a randomized controlled trial

Background

Management of inoperable chronic thromboembolic pulmonary hypertension (CTEPH) remains a clinical challenge. Currently, riociguat, a soluble guanylate-cyclase stimulator is recommended by international guidelines. More recently, balloon pulmonary angioplasty (BPA) develops as an alternative treatment for inoperable CTEPH.

Method

This study is a single-center randomized controlled trial. Subjects with inoperable CTEPH are randomized into either a BPA combined with riociguat or riociguat monotherapy group (2:1) and observed for 12 months after initiation of treatment. The primary endpoint is the change in pulmonary vascular resistance from baseline to 12 months after initiation of treatment. The secondary endpoints include 6-min walk distance (6MWD), WHO-FC, NT-proBNP, SF-36, and other hemodynamic parameters. Safety endpoints are analyzed too.

Discussion

This study aims to compare the efficacy and safety of BPA combined with riociguat and riociguat monotherapy for inoperable CTEPH.

Trial registration

Chinese Clinical Trial Registry ChiCTR2000032403. Registered on 27 April 2020.

Sex and survival following pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension: a Scandinavian observational cohort study

Studies have suggested sex-related survival differences in chronic thromboembolic pulmonary hypertension (CTEPH). Whether long-term prognosis differs between men and women following pulmonary endarterectomy for CTEPH remains unclear. We investigated sex-specific survival after pulmonary endarterectomy for CTEPH. We included all patients who underwent pulmonary endarterectomy for CTEPH at two Scandinavian centers and obtained baseline characteristics and vital statuses from patient charts and national health-data registers. Propensity scores and weighting were used to account for baseline differences. Flexible parametric survival models were employed to estimate the association between sex and all-cause mortality and the absolute survival differences. The expected survival in an age-, sex-, and year of surgery matched general population was obtained from the Human Mortality Database, and the relative survival was used to estimate cause-specific mortality. A total of 444 patients were included, comprising 260 (59%) men and 184 (41%) women. Unadjusted 30-day mortality was 4.2% in men versus 9.8% in women (p = 0.020). In weighted analyses, long-term survival did not differ significantly in women compared with men (hazard ratio: 1.36; 95% confidence interval: 0.89–2.06). Relative survival at 15 years conditional on 30-day survival was 94% (79%–107%) in men versus 75% (59%–88%) in women. In patients who underwent pulmonary endarterectomy for CTEPH, early mortality was higher in women compared with men. After adjustment for differences in baseline characteristics, female sex was not associated with long-term survival. However, relative survival analyses suggested that the observed survival in men was close to the expected survival in the matched general population, whereas survival in women deviated notably from the matched general population.

Effects of BPA on right ventricular mechanical dysfunction in patients with inoperable CTEPH - A cardiac magnetic resonance study

PURPOSE

The aim of this study was to assess effects of balloon pulmonary angioplasty (BPA) on right ventricular (RV) mechanical dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) via MRI.

METHOD

MRI at 1.5 Tesla and right heart catheterization were performed before and 6 months after BPA in 30 CTEPH patients (mean age 63.4 ± 10.6 years; 17 female). Feature-tracking strain analysis, including global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain, was performed and compared with right ventricular function, myocardial remodelling (assessed by native T1 times), and pulmonary haemodynamics (mean pulmonary arterial pressure and pulmonary vascular resistance).

RESULTS

RVEF (35.9% to 48.4%) increased and mPAP (42.1 mmHg to 33.1 mmHg) and PVR (551.8 to 377.7 dyn∙s/cm⁵) decreased after BPA (all p < 0.0001). Moreover, RV strain increased (GLS -19.9 to -24.0%, p = 0.0003; GCS -9.4 to -11.0%, p = 0.0022; GRS 38.2 to 50.7%, p = 0.001) and septal native area-adjusted T1 time (AA-T1) decreased (1019.4 to 988.7 ms, p < 0.0001). GLS revealed the best correlations with RVEF (before BPA r = -0.75; after BPA r = -0.54), mPAP (r = 0.36; r = 0.52), PVR (r = 0.49; r = 0.48), and AA-T1 (r = 0.44; 0.19).

CONCLUSION

RV mechanical dysfunction, pulmonary haemodynamics, and myocardial remodelling are markedly improved by BPA. Moreover, RV strain values showed good correlations with RV function, pulmonary haemodynamics, and myocardial remodelling. Therefore, strain analysis might provide new insights regarding therapy outcome, monitoring, and prognosis.

Chronic thromboembolic pulmonary hypertension: anticoagulation and beyond

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication in pulmonary embolism (PE) survivors, characterized by chronic vascular occlusion and pulmonary hypertension. The identification and diagnosis of CTEPH requires a stepwise approach, starting with symptom evaluation, functional evaluation, screening imaging, and progressing to interventional hemodynamic assessment. On the backbone of anticoagulation, CTEPH management necessitates a multidisciplinary approach. Surgical pulmonary thromboendarterectomy (PTE) is the only potentially curative option. In nonoperable disease or residual disease after PTE, interventional balloon pulmonary angioplasty and/or pulmonary-vasodilator therapies can be offered, in collaboration with interventional and vascular pulmonary colleagues. As it is a disease that can cause high morbidity and mortality, CTEPH requires a high index of suspicion to diagnose and treat in patients following PE.

Chronic thromboembolic pulmonary hypertension: Initial experience of patients undergoing pulmonary thromboendarterectomy

INTRODUCTION AND OBJECTIVES

Pulmonary endarterectomy (PEA) is a potentially curative procedure in patients with chronic thromboembolic pulmonary hypertension (CTEPH). This study reports the initial experience of a Portuguese PH center with patients undergoing PEA at an international surgical reference center.

METHODS

Prospective observational study of consecutive CTEPH patients followed at a national PH center, who underwent PEA at an international surgical reference center between October 2015 and March 2019. Clinical, functional, laboratory, imaging and hemodynamic parameters were obtained in the 12 months preceding the surgery and repeated between four and six months after PEA.

RESULTS

27 consecutive patients (59% female) with a median age of 60 (49-71) years underwent PEA. During a median follow-up of 34 (21-48) months, there was an improvement in functional class in all patients, with only one cardiac death. From a hemodynamic perspective, there was a reduction in mean pulmonary artery pressure from 48 (42-59) mmHg to 26 (22-38) mmHg, an increase in cardiac output from 3.3 (2.9-4.0) L/min to 4.9 (4.2-5.5) L/min and a reduction in pulmonary vascular resistance from 12.1 (7.2-15.5) uW to 3.5 (2.6-5,2) uW. During the follow-up, 44% (n=12) of patients had no PH criteria, 44% (n=12) had residual PH and 11% (n=3) had PH recurrence. There was a reduction of N-terminal pro-B-type natriureticpeptide from 868 (212-1730) pg/mL to 171 (98-382) pg/mL. Rright ventricular systolic function parameters revealed an improvement in longitudinal systolic excursion and peak velocity of the plane of the tricuspid ring from 14 (13-14) mm and 9 (8-10) cm/s to 17 (16-18) mm and 13 (11-15) cm/s, respectively. Of the 26 patients with preoperative right ventricular dysfunction, 85% (n=22) recovered. The proportion of patients on specific vasodilator therapy decreased from 93% to 44% (p<0.001) and the proportion of those requiring oxygen therapy decreased from 52% to 26% (p=0.003). The six-minute walk test distance increased by about 25% compared to the baseline and only eight patients had significant desaturation during the test.

CONCLUSION

Pulmonary endarterectomy performed at an experienced high-volume center is a safe procedure with a very favorable medium-term impact on functional, hemodynamic and right ventricular function parameters in CTEPH patients with operable disease. It is possible for PH centers without PEA differentiation to refer patients safely and effectively to an international surgical center in which air transport is necessary.

Safety and efficacy of balloon pulmonary angioplasty in a Portuguese pulmonary hypertension expert center

INTRODUCTION

Balloon pulmonary angioplasty (BPA) is an alternative therapy in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) or residual/recurrent pulmonary hypertension (PH) after surgery. The aim of this study was to assess the short-term efficacy and safety of a BPA program.

METHODS

This prospective single-center study included all BPA sessions performed in CTEPH patients between 2017 and 2019. Clinical assessment including WHO functional class, plasma biomarkers, 6-min walk test (6MWT) and right heart catheterization was performed at baseline and six months after the last BPA session.

RESULTS

A total of 57 BPA sessions were performed in 11 CTEPH patients (64% with inoperable disease, 82% under pulmonar vasodilator therapy). Nine patients completed both the BPA program and a minimum six-month follow-up period. There were significant improvements in WHO functional class (p=0.004) and 6MWT (mean increase of 42 m; p=0.050) and a trend for significant hemodynamic improvement: 25% decrease in mean pulmonary artery pressure (mPAP) (p=0.082) and 42% decrease in pulmonary vascular resistance (PVR) (p=0.056). In the group of patients with severely impaired hemodynamics (three patients with mPAP >40 mmHg), the reduction was significant: 51% in mPAP (p=0.013) and 67% in PVR (p=0.050). Prostacyclin analogs and long-term oxygen therapy were withdrawn in all patients. Minor complications were recorded in 25% of patients. There were no major complications or deaths.

CONCLUSIONS

A BPA strategy on top of pulmonary vasodilator therapy further improves symptoms, exercise capacity and hemodynamics with an acceptable risk-benefit ratio in patients with inoperable CTEPH or residual/recurrent PH after surgery.

A model for estimating the health economic impact of earlier diagnosis of chronic thromboembolic pulmonary hypertension

Background

Diagnostic delay of chronic thromboembolic pulmonary hypertension (CTEPH) exceeds 1 year, contributing to higher mortality. Health economic consequences of late CTEPH diagnosis are unknown. We aimed to develop a model for quantifying the impact of diagnosing CTEPH earlier on survival, quality-adjusted life-years (QALYs) and healthcare costs.

Material and methods

A Markov model was developed to estimate lifelong outcomes, depending on the degree of delay. Data on survival and quality of life were obtained from published literature. Hospital costs were assessed from patient records (n=498) at the Amsterdam UMC – VUmc, which is a Dutch CTEPH referral center. Medication costs were based on a mix of standard medication regimens.

Results

For 63-year-old CTEPH patients with a 14-month diagnostic delay of CTEPH (median age and delay of patients in the European CTEPH Registry), lifelong healthcare costs were estimated at EUR 117 100 for a mix of treatment options. In a hypothetical scenario of maximal reduction of current delay, improved survival was estimated at a gain of 3.01 life-years and 2.04 QALYs. The associated cost increase was EUR 44 654, of which 87% was due to prolonged medication use. This accounts for an incremental cost–utility ratio of EUR 21 900/QALY.

Conclusion

Our constructed model based on the Dutch healthcare setting demonstrates a substantial health gain when CTEPH is diagnosed earlier. According to Dutch health economic standards, additional costs remain below the deemed acceptable limit of EUR 50 000/QALY for the particular disease burden. This model can be used for evaluating cost-effectiveness of diagnostic strategies aimed at reducing the diagnostic delay.

This constructed model based on the Dutch healthcare setting can be used for evaluating cost-effectiveness of diagnostic strategies aimed at reducing the diagnostic delay of chronic thromboembolic pulmonary hypertensionhttps://bit.ly/35yXPM3

Prediction of chronic thromboembolic pulmonary hypertension with standardised evaluation of initial computed tomography pulmonary angiography performed for suspected acute pulmonary embolism

Objectives

Closer reading of computed tomography pulmonary angiography (CTPA) scans of patients presenting with acute pulmonary embolism (PE) may identify those at high risk of developing chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to validate the predictive value of six radiological predictors that were previously proposed.

Methods

Three hundred forty-one patients with acute PE were prospectively followed for development of CTEPH in six European hospitals. Index CTPAs were analysed post hoc by expert chest radiologists blinded to the final diagnosis. The accuracy of the predictors using a predefined threshold for ‘high risk’ (≥ 3 predictors) and the expert overall judgment on the presence of CTEPH were assessed.

Results

CTEPH was confirmed in nine patients (2.6%) during 2-year follow-up. Any sign of chronic thrombi was already present in 74/341 patients (22%) on the index CTPA, which was associated with CTEPH (OR 7.8, 95%CI 1.9–32); 37 patients (11%) had ≥ 3 of 6 radiological predictors, of whom 4 (11%) were diagnosed with CTEPH (sensitivity 44%, 95%CI 14–79; specificity 90%, 95%CI 86–93). Expert judgment raised suspicion of CTEPH in 27 patients, which was confirmed in 8 (30%; sensitivity 89%, 95%CI 52–100; specificity 94%, 95%CI 91–97).

Conclusions

The presence of ≥ 3 of 6 predefined radiological predictors was highly specific for a future CTEPH diagnosis, comparable to overall expert judgment, while the latter was associated with higher sensitivity. Dedicated CTPA reading for signs of CTEPH may therefore help in early detection of CTEPH after PE, although in our cohort this strategy would not have detected all cases.

Key Points

• Three expert chest radiologists re-assessed CTPA scans performed at the moment of acute pulmonary embolism diagnosis and observed a high prevalence of chronic thrombi and signs of pulmonary hypertension.

• On these index scans, the presence of ≥ 3 of 6 predefined radiological predictors was highly specific for a future diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH), comparable to overall expert judgment.

• Dedicated CTPA reading for signs of CTEPH may help in early detection of CTEPH after acute pulmonary embolism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08364-0.

Selexipag for the treatment of chronic thromboembolic pulmonary hypertension

Treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) remain limited. Selexipag, an oral selective IP prostacyclin-receptor agonist approved for pulmonary arterial hypertension, is a potential treatment option for CTEPH.In this multicentre, randomised, double-blind, placebo-controlled study, 78 Japanese patients with inoperable CTEPH or persistent/recurrent pulmonary hypertension after pulmonary endarterectomy and/or balloon pulmonary angioplasty were randomly assigned to receive placebo or selexipag. The primary endpoint was the change in pulmonary vascular resistance (PVR) from baseline to week 20. The secondary endpoints were changes in other haemodynamic parameters, 6-min walk distance (6 WMD), Borg Dyspnoea Scale score, World Health Organisation (WHO) functional class, EuroQol 5 dimensions 5-level and N-terminal pro-brain natriuretic peptide.The change in PVR was -98.2±111.3 dyn·s·cm^-5 and -4.6±163.6 dyn·s·cm^-5 in the selexipag and placebo groups, respectively (mean difference, -93.5 dyn·s·cm^-5; 95% confidence interval, -156.8, -30.3; p=0.006). The changes in cardiac index (p<0.001) and Borg Dyspnoea Scale score (p=0.036) were also significantly improved over placebo. 6WMD and WHO functional class were not significantly improved. The common adverse events in the selexipag group were corresponded to those generally observed following a prostacyclin analogue is administered.Selexipag significantly improved PVR and other haemodynamic variables in patients with CTEPH, although exercise capacity remained unchanged. Further large-scale investigation is necessary to prove the role of selexipag in CTEPH.

Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension: A STS Database Analysis

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is optimally treated by pulmonary thromboendarterectomy (PEA). Treatment effectiveness has been evaluated principally using single-center series. Data from the Society of Thoracic Surgeons Adult Cardiac Surgery Database were used to evaluate a volume-outcomes relationship for PEA.

METHODS

Circulatory arrest procedures performed between 2012-2018 were identified through an STS-ACSD Participant User File. For descriptive purposes, total center procedural volume categories were computed: low (0-75^th percentile, <16); medium (76-95^th percentile, 16-100); high (>95^th percentile, >100). Mixed effect modeling was used to evaluate the effect of center procedural volume (modeled continuously) on operative mortality, adjusting for preoperative risk factors, with centers as a random effect.

RESULTS

There were 1,358 cases performed across 64 centers [n/N: low (49/172); medium (12/527); high (3/659)], with 42 centers performing <10 operations during the period. Procedural volume increased 2.6-fold between 2012-2018 (94 versus 339), with 79% of the change in volume accounted for by 4 centers. The mean (IQR) preoperative pulmonary artery systolic value was 74 mmHg (57-88), with no difference (p=0.55) by center volume categories. In unadjusted analysis, patients at high volume centers required fewer transfusions, had shorter ventilator and intensive care unit (ICU) duration, lower frequency of postoperative extracorporeal membrane oxygenation (ECMO), and trended lower mortality (2.1% vs 5.2%, p=0.051). Operative mortality was lower at higher volume centers (OR_adjusted,_{1-case-increase}: 0.997; CI95%: 0.994-1.0; p=0.025).

CONCLUSIONS

Most PEA procedures are performed among a small number of centers, with high-volume hospitals having favorable outcomes. These data suggest a potential role for PEA regionalization.

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.

A Feasibility Study on Using Single-Photon Emission Computed Tomography Pulmonary Perfusion/Ventilation Imaging for the Diagnosis of Chronic Thromboembolic Pulmonary Hypertension and Patient Risk Assessment

Objective

The study is designed to evaluate the diagnostic ability of single-photon emission computed tomography (SPECT) pulmonary ventilation/perfusion (V/Q) imaging in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and investigate its feasibility in assessing patient risk.

Methods

A total of 83 patients suspected of having CTEPH who received V/Q tomography were retrospectively analyzed. The consistency between SPECT V/Q imaging and pulmonary angiography was compared to investigate the correlation between the percentage of pulmonary perfusion defect score (PPDs%) and the hemodynamic indices. Patients were grouped according to the pulmonary arterial hypertension risk stratification, and the V/Q imaging results were compared between different groups.

Results

For the 1494 pulmonary segments of the 83 patients, the sensitivity, specificity, and accuracy of identifying pulmonary segments with defects using V/Q imaging was 87.05%, 82.78% (668/807), and 84.74% (1266/1494), respectively. The average PPDs% (58.8 ± 12.6%) was positively correlated with the mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), and right ventricular pressure (RVP; r =0.316, 0.318, and 0.432, respectively; P < 0.05) and negatively correlated with the six-minute walk distance (6MWD; r = −0.309; P < 0.05). There were 37 patients in the low-risk group and 46 in the medium-high-risk group. The number of pulmonary segments with perfusion defects (NPSPDs) and PPDs% were higher in the medium-high risk than in the low-risk group (t = −6.721, −5.032; P < 0.05). In the low- and medium-high-risk groups, the cut-off values for the NPSPDs (7.2 ± 2.1 and 10.2 ± 2.0) and PPDs% (51.9 ± 11.1% and 64.3 ± 11.1%,) were 8.5 and 61.25%, respectively.

Conclusion

SPECT V/Q imaging achieved an accurate diagnosis of CTEPH. The semi-quantitative analysis index (PPDs%) was correlated with the hemodynamic indices and 6MWD. SPECT V/Q could be used for the preoperative risk assessment of patients with CTEPH.

Catheter-based therapies in acute and chronic pulmonary embolism

PURPOSE OF REVIEW

The aim of this study is to summarize currently available catheter-based therapies in acute and chronic pulmonary embolic disease.

RECENT FINDINGS

Catheter-based therapies to treat acute pulmonary embolism and its sequelae such as chronic thromboembolic pulmonary hypertension (CTEPH) are emerging as the next frontier within interventional cardiology. However, the true benefit of these catheter-based therapies in intermediate-risk and high-risk pulmonary embolism and CTEPH remains unclear. The current evidence supporting such interventions comes primarily from small single-arm studies in acute pulmonary embolism and case series in CTEPH.

SUMMARY

Appropriately powered randomized controlled trials with meaningful clinical outcomes as endpoints are needed to elucidate the true benefit of catheter-based therapies in pulmonary embolism compared with other treatment modalities such as anticoagulation and systemic thrombolysis in acute pulmonary embolism and riociguat and pulmonary endarterectomy in CTEPH.

Identification of chronic thromboembolic pulmonary hypertension on CTPAs performed for diagnosing acute pulmonary embolism depending on level of expertise

BACKGROUND

Expert reading often reveals radiological signs of chronic thromboembolic pulmonary hypertension (CTEPH) or chronic PE on computed tomography pulmonary angiography (CTPA) performed at the time of acute pulmonary embolism (PE) presentation preceding CTEPH. Little is known about the accuracy and reproducibility of CTPA reading by radiologists in training in this setting.

OBJECTIVES

To evaluate 1) whether signs of CTEPH or chronic PE are routinely reported on CTPA for suspected PE; and 2) whether CTEPH-non-expert readers achieve comparable predictive accuracy to CTEPH-expert radiologists after dedicated instruction.

METHODS

Original reports of CTPAs demonstrating acute PE in 50 patients whom ultimately developed CTEPH, and those of 50 PE who did not, were screened for documented signs of CTEPH. All scans were re-assessed by three CTEPH-expert readers and two CTEPH-non-expert readers (blinded and independently) for predefined signs and overall presence of CTEPH.

RESULTS

Signs of chronic PE were mentioned in the original reports of 14/50 cases (28%), while CTEPH-expert radiologists had recognized 44/50 (88%). Using a standardized definition (≥3 predefined radiological signs), moderate-to-good agreement was reached between CTEPH-non-expert readers and the experts' consensus (k-statistics 0.46; 0.61) at slightly lower sensitivities. The CTEPH-non-expert readers had moderate agreement on the presence of CTEPH (κ-statistic 0.38), but both correctly identified most cases (80% and 88%, respectively).

CONCLUSIONS

Concomitant signs of CTEPH were poorly documented in daily practice, while most CTEPH patients were identified by CTEPH-non-expert readers after dedicated instruction. These findings underline the feasibility of achieving earlier CTEPH diagnosis by assessing CTPAs more attentively.

Pulmonary endarterectomy

Chronic thromboembolic pulmonary hypertension is an underdiagnosed condition. Patients typically present with the symptoms of right heart failure. Diagnosis is usually done by radionuclide ventilation/perfusion (VQ) scan, high-quality multidetector computed tomography (CT) or pulmonary angiography at expert centers. Pulmonary endarterectomy remains the corner stone in management of chronic thromboembolic pulmonary hypertension. Deep hypothermic circulatory arrest is commonly used for the operation at most centers. In-hospital mortality ranges from 1.7 to 14.2%. Pulmonary hemorrhage, reperfusion lung injury, and right ventricular failure remain major early post-operative concerns. Five-year survival is reported to be 76 to 89%. Long-term outcome depends on residual pulmonary hypertension. Balloon pulmonary angioplasty and medical management play an adjunctive role. Here, we provide a comprehensive review on surgical management of chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension anno 2021

PURPOSE OF REVIEW

In the past decades, the diagnostic and therapeutic management of chronic thromboembolic pulmonary hypertension (CTEPH) has been revolutionized.

RECENT FINDINGS

Advances in epidemiological knowledge and follow-up studies of pulmonary embolism patients have provided more insight in the incidence and prevalence. Improved diagnostic imaging techniques allow accurate assessment of the location and extend of the thromboembolic burden in the pulmonary artery tree, which is important for the determination of the optimal treatment strategy. Next to the pulmonary endarterectomy, the newly introduced technique percutaneous pulmonary balloon angioplasty and/or P(A)H-targeted medical therapy has been shown to be beneficial in selected patients with CTEPH and might also be of importance in patients with chronic thromboembolic pulmonary vascular disease.

SUMMARY

In this era of a comprehensive approach to CTEPH with different treatment modalities, a multidisciplinary approach guides management decisions leading to optimal treatment and follow-up of patients with CTEPH.

Chronic thromboembolic pulmonary hypertension in patients with antiphospholipid syndrome: Risk factors and management

BACKGROUND

Antiphospholipid syndrome (APS) may cause chronic thromboembolic pulmonary hypertension (CTEPH). Current knowledge regarding prevalence and risk factors for CTEPH among APS patients is limited. We sought to determine clinical features and biomarkers that could identify APS subjects suffering from CTEPH, and describe the prevalence, course and treatment outcomes of patients with APS-CTEPH.

METHODS

504 APS patients were treated in our center during 2008 to 2019. We studied clinical and laboratory features of 69 APS patients, comparing 19 patients diagnosed with CTEPH (APS-CTEPH) and treated accordingly, with 50 consecutive age and gender matched patients with no evidence of pulmonary hypertension (APS-No-CTEPH).

RESULTS

CTEPH prevalence was 3.8% in our APS cohort and was linked with the following parameters: primary APS (p < 0.05); prior pulmonary embolism (p < 0.001); recurrent venous thromboembolism (VTE) (p < 0.001); lower platelet counts (p < 0.001); triple anti-phospholipid antibodies positivity (p < 0.001), higher titers of anti-cardiolipin IgG (p < 0.001), anti-B2GPI IgG (p < 0.001), and high Russell viper venom time ratio (RVVT-ratio) (p < 0.05). Additionally, history of catastrophic APS was more prevalent in APS-CTEPH vs APS-No-CTEPH (p < 0.05). Of APS-CTEPH patients, 15/19 underwent pulmonary endarterectomy (PEA): In 12/15 the procedure was elective and resulted in good perioperative and long-term outcomes, while only 1 of 3 patients that underwent urgent PEA survived.

CONCLUSIONS

CTEPH is relatively common in APS. Primary APS, prior PE, recurrent VTE, thrombocytopenia and specific anti-phospholipid antibodies predict CTEPH in APS. Active assessment for CTEPH in APS patients should be considered, as PEA was found to be effective and relatively safe, especially if electively performed.

The long-term survival in patients with chronic thromboembolic pulmonary hypertension: experience from a single center in China

The long-term prognosis of patients with chronic thromboembolic pulmonary hypertension (CTEPH) receiving different treatments is deserved to be analyzed in modern era of CTEPH treatment. From 2013 to 2019, a total of 364 patients diagnosed with CTEPH were retrospectively included, 14 patients were lost during follow-up. Among 350 patients included in the final analysis: 123 underwent pulmonary endarterectomy (PEA), 121 received balloon pulmonary angioplasty (BPA), and 106 treated with targeted drug alone. The median period of follow-up was 51.2 months, the estimated survival at 1-, 3-, 5- and 7-year was 97.1%, 93.3%, 86.9%, and 82.0% for the whole cohort; 100%, 99.20%, 96.5% and 92.5% in PEA group; 98.4%, 97.4%, 95.3% and 89.3% in BPA group;92.5%, 81.9%, 70.1% and 66.8% in patients who received targeted drug alone. In comparing with targeted treatment along, results of multivariate Cox analysis after adjusting the confounders showed that receiving PEA decreased the risk of death by 83% (HR [hazard ratio] 0.17, 95% CI [Confidence interval] 0.07-0.44) and receiving BPA decreased the risk of death by 89% (HR 0.11, 95% CI 0.04-0.29). In conclusion, the estimated survival of CTEPH patients at 1-, 3-, 5- and 7-year was 97.1%, 93.3%, 86.9%, and 82.0% respectively. The intervention of revascularization, including PEA and BPA, were preferred than treating with targeted drug alone in the view of long-term prognosis of CTEPH.

Incidence and predictors of chronic thromboembolic pulmonary hypertension following acute pulmonary embolism: An echocardiography guided approach

There is significant variability in the worldwide epidemiology of chronic thromboembolic pulmonary hypertension (CTEPH). We thereby aim to determine the incidence and predictors of CTEPH, following an episode of acute pulmonary embolism (PE), using non-invasive modalities. Patients with acute PE were prospectively followed-up and after receiving at least 3 months of effective anticoagulation, persistently symptomatic patients with echocardiographic evidence of persistent pulmonary hypertension, were investigated further for CTEPH. Incidence of CTEPH was 8.19%. Delayed presentation, higher pulmonary artery pressures at presentation and discharge, and greater thrombotic burden were significant predictors for the development of CTEPH following acute PE.

Clinical application of pulmonary vascular resistance in patients with pulmonary arterial hypertension

Pulmonary arterial hypertension is a type of malignant pulmonary vascular disease, which is mainly caused by the increase of pulmonary vascular resistance due to the pathological changes of the pulmonary arteriole itself, which eventually leads to right heart failure and death. As one of the diagnostic indicators of hemodynamics, pulmonary vascular resistance plays an irreplaceable role in the pathophysiology, diagnosis and treatment of pulmonary arterial hypertension. It provides more references for the evaluation of pulmonary arterial hypertension patients. This article summarizes the clinical application of pulmonary vascular resistance in patients with pulmonary arterial hypertension.

Chronic thromboembolic pulmonary hypertension in Australia and New Zealand: An analysis of the PHSANZ registry

BACKGROUND AND OBJECTIVE

Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious condition occurring in 2%-4% of patients after acute pulmonary embolism. Pulmonary endarterectomy (PEA) is a potential cure for technically operable disease. The epidemiology and long-term outcomes of CTEPH have not been previously described in Australia and New Zealand.

METHODS

Data were extracted from the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) registry for patients diagnosed with CTEPH between January 2004 and March 2020. Baseline characteristics, treatment strategies, outcome data and long-term survival are reported.

RESULTS

A total of 386 patients were included with 146 (37.8%) undergoing PEA and 240 (62.2%) in the non-PEA group. PEA patients were younger (55 ± 16 vs. 62 ± 16 years, p < 0.001) with higher baseline 6-min walk distance (6MWD; 405 ± 122 vs. 323 ± 146 m, p = 0.021), whilst both groups had similar baseline pulmonary haemodynamics. Pulmonary hypertension-specific therapy was used in 54% of patients post-PEA and 88% in the non-PEA group. The 1-, 3- and 5-year survival rates were 93%, 87% and 84% for the PEA group compared to 86%, 73% and 62%, respectively, for the non-PEA group (p < 0.001). Multivariate survival analysis showed baseline 6MWD was an independent predictor of survival in both operated and medically managed patients.

CONCLUSION

In this first multicentre report of CTEPH in Australia and New Zealand, long-term survival is comparable to that in other contemporary CTEPH registries. However, PEA was only performed in a minority of CTEPH patients (37.8%) and significantly less than overseas reports. Greater awareness of PEA and improved patient access to experienced CTEPH centres are important priorities.

Global trends in chronic thromboembolic pulmonary hypertension clinical trials and dissemination of results

Treatment options for chronic thromboembolic pulmonary hypertension (CTEPH) are rapidly expanding. The purpose of this study is to identify trends in CTEPH clinical trials and the publication of results. We performed a worldwide review of completed and ongoing clinical trials through searching the ClinicalTrials.gov database and the World Health Organization International Clinical Trials Registry Platform for "CTEPH" and related terms. Entries were classified as pharmaceutical/procedural interventions (Group 1), all other clinical trials (Group 2) and patient registries (Group 3). Trial characteristics and national affiliation were recorded. PubMed was searched for related publications. There were 117 clinical trials registry entries after removing duplicates and non-target records. Group 1 comprised 29 pharmaceutical, 15 procedural, and four combined interventions starting in 2005, 2010, and 2016, respectively. Riociguat and balloon pulmonary angioplasty were the most frequent pharmaceutical and procedural interventions, respectively. The proportion of procedural trials increased over time from 0% of those in 2005-2009 to 29% in 2010-2014 and 54% in 2015-2020. There were 56 entries in Group 2 and 13 in Group 3. Japan was the most frequent national affiliation and the most frequent participating country, present in 28% of all trials. The proportion of entries with published results was highest with Group 3 (62%) and lowest with Group 1 (27%). Thirty percent of all publications occurred in 2020. In conclusion, CTEPH clinical trials are increasingly procedural based, with growth largely attributable to Japan and balloon pulmonary angioplasty. Most trials have not published, but results from balloon pulmonary angioplasty clinical trials are anticipated soon.

A computational model of contributors to pulmonary hypertensive disease: impacts of whole lung and focal disease distributions

Pulmonary hypertension has multiple etiologies and so can be difficult to diagnose, prognose, and treat. Diagnosis is typically made via invasive hemodynamic measurements in the main pulmonary artery and is based on observed elevation of mean pulmonary artery pressure. This static mean pressure enables diagnosis, but does not easily allow assessment of the severity of pulmonary hypertension, nor the etiology of the disease, which may impact treatment. Assessment of the dynamic properties of pressure and flow data obtained from catheterization potentially allows more meaningful assessment of the strain on the right heart and may help to distinguish between disease phenotypes. However, mechanistic understanding of how the distribution of disease in the lung leading to pulmonary hypertension impacts the dynamics of blood flow in the main pulmonary artery and/or the pulmonary capillaries is lacking. We present a computational model of the pulmonary vasculature, parameterized to characteristic features of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension to help understand how the two conditions differ in terms of pulmonary vascular response to disease. Our model incorporates key features known to contribute to pulmonary vascular function in health and disease, including anatomical structure and multiple contributions from gravity. The model suggests that dynamic measurements obtained from catheterization potentially distinguish between distal and proximal vasculopathy typical of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension. However, the model suggests a non-linear relationship between these data and vascular structural changes typical of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension which may impede analysis of these metrics to distinguish between cohorts.

Clinical and physiological characteristics of, medically treated, chronic thromboembolic pulmonary hypertension patients in Saudi Arabia: A single center experience

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is uncommon but well-known sequel of venous thromboembolism (VTE). At present, it is the only potential curable subtype of pulmonary hypertension. The aim of this study is to describe the medically treated-CTEPH patients' characteristics in a single specialized PH center in Saudi Arabia.

METHODS

This study presents demographic, clinical, physiological, and hemodynamic characteristics of medically treated-CTEPH patients in a single PH center, namely Prince Sultan Military Medical City, Riyadh, Saudi Arabia. Both incident and prevalent cases are included.

RESULTS

A total of 20 patients with a confirmed diagnosis of CTEPH were included. Mean age at diagnosis was 43 years with a female preponderance of 75%. Most common presenting symptom was dyspnea (100%) followed by syncope (58%). At diagnosis, a mean of 15 ± 10 months had passed since symptoms onset. About 45% of patients were in WHO functional class IV. At baseline, mean 6-min walk distance was 354.3 meters. Overall, VTE was the most frequent risk factor identified (65% of all patients). Nearly 30% of patients had sickle cell disease. 13 out of 20 patients had radiographic (i.e., computed tomography [CT] pulmonary angiogram) features of chronic thromboembolism. About 75% of patients were found to have distal disease on radiographic imaging. At the time of diagnosis, 7 out of 20 (35%) patients demonstrated right ventricular failure on echocardiography. Mean tricuspid annular plane systolic excursion was 17.7 ± 1.20. Median NT-proBNP levels were found to be 688 pg/ml. Mean diffusing capacity for carbon monoxide was 74.8%.

CONCLUSIONS

Diagnosis of CTEPH was established at a relatively younger age. Majority of patients had advanced but distal disease on radiographic imaging, not amenable to surgery.

Characteristics of chronic thromboembolic pulmonary hypertension in Ireland

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare and under-recognised complication of acute pulmonary embolism. Information regarding the characteristics of CTEPH in Ireland is limited, and the aim of this retrospective cohort study was to address this knowledge gap. Seventy-two cases of CTEPH were diagnosed in the National Pulmonary Hypertension Unit (NPHU) in Ireland between 2010 and 2020. This accounted for 6% of all referrals to the unit and translates to an estimated annual incidence of 1.39 per million population (95% confidence interval, 0.33-2.46). The prevalence of diagnosed CTEPH in Ireland in 2020 was estimated at 12.05 per million population (95% CI 9.00-15.10). The average duration of symptoms prior to CTEPH diagnosis was 23 (±22) months. Patients with CTEPH were more likely to be male (n = 40, 56%), older (60 ± 17 years) and have identifiable risk factors for CTEPH (n = 61, 85%) at diagnosis. Regarding treatment, pulmonary hypertension (PH) vasodilator therapy was prescribed in 75% (n = 54) within 12 months of diagnosis, inferior vena cava filters were placed in 24% (n = 17) and 97% (n = 70) of cases were anticoagulated. Pulmonary endarterectomy was performed in 35% (n = 25), balloon pulmonary angioplasty in 6% (n = 4). One-, three- and five-year survival was 93%, 80% and 65% from the time of diagnosis, and this was significantly better in patients who underwent pulmonary endarterectomy (p = 0.01). This is the first study describing the characteristics of CTEPH in Ireland and highlights suboptimal disease recognition and referral for the assessment for pulmonary endarterectomy.

Epidemiology and Management of Chronic Thromboembolic Pulmonary Hypertension in Greece. Real-World Data from the Hellenic Pulmonary Hypertension Registry (HOPE)

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is a rare disease with poor prognosis if left untreated, characterized by pulmonary vascular bed obstruction due to unresolving thromboembolic material. The Hellenic pulmonary hypertension registry (HOPE) was launched in Greece in early 2015 and enrolls patients from all pulmonary hypertension subgroups in Greece. In total, 98 patients with CTEPH were enrolled from January 2015 until November 2019. Of these patients, 55.1% represented incident population, 50% were classified in the World Health Organization functional class II and 49% had a history of acute pulmonary embolism. The median values of pulmonary vascular resistance (PVR) and cardiac index were 7.4 (4.8) WU and 2.4 (1.0) L/min/m², respectively, the mean diffusing capacity for carbon monoxide was 74.8 ± 20.6%, the median 6-minute walk distance was 347 (220) meters and the median value of N Terminal-pro brain natriuretic peptide was 506.0 (1450.0) pg/mL. In total, 60.2% of the patients were under pulmonary arterial hypertension-targeted therapy at the time of enrolment; specifically, riociguat was received by 35.7% of the patients and combination therapy was the preferred strategy for 16% of the patients. In total, 74 patients were evaluated for pulmonary endarterectomy (PEA), 34 (45.9%) were assessed as operable but only 23 of those (31.1%) finally underwent PEA. The remaining 40 patients were ineligible for PEA according to the operability assessment and 13 (17.6%) of them underwent balloon pulmonary angioplasty. The age of the non-operable patients was significantly higher than the operable patients (p < 0.001), while there was no significant difference with regard to the history of coagulopathies between the operable and non-operable patients (p = 0.33).

Performance of a 3D convolutional neural network in the detection of hypoperfusion at CT pulmonary angiography in patients with chronic pulmonary embolism: a feasibility study

BACKGROUND

Chronic pulmonary embolism (CPE) is a life-threatening disease easily misdiagnosed on computed tomography. We investigated a three-dimensional convolutional neural network (CNN) algorithm for detecting hypoperfusion in CPE from computed tomography pulmonary angiography (CTPA).

METHODS

Preoperative CTPA of 25 patients with CPE and 25 without pulmonary embolism were selected. We applied a 48%-12%-40% training-validation-testing split (12 positive and 12 negative CTPA volumes for training, 3 positives and 3 negatives for validation, 10 positives and 10 negatives for testing). The median number of axial images per CTPA was 335 (min-max, 111-570). Expert manual segmentations were used as training and testing targets. The CNN output was compared to a method in which a Hounsfield unit (HU) threshold was used to detect hypoperfusion. Receiver operating characteristic area under the curve (AUC) and Matthew correlation coefficient (MCC) were calculated with their 95% confidence interval (CI).

RESULTS

The predicted segmentations of CNN showed AUC 0.87 (95% CI 0.82-0.91), those of HU-threshold method 0.79 (95% CI 0.74-0.84). The optimal global threshold values were CNN output probability ≥ 0.37 and ≤ -850 HU. Using these values, MCC was 0.46 (95% CI 0.29-0.59) for CNN and 0.35 (95% CI 0.18-0.48) for HU-threshold method (average difference in MCC in the bootstrap samples 0.11 (95% CI 0.05-0.16). A high CNN prediction probability was a strong predictor of CPE.

CONCLUSIONS

We proposed a deep learning method for detecting hypoperfusion in CPE from CTPA. This model may help evaluating disease extent and supporting treatment planning.

Derivation and characterisation of endothelial cells from patients with chronic thromboembolic pulmonary hypertension

Pulmonary endarterectomy (PEA) resected material offers a unique opportunity to develop an in vitro endothelial cell model of chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to comprehensively analyze the endothelial function, molecular signature, and mitochondrial profile of CTEPH-derived endothelial cells to better understand the pathophysiological mechanisms of endothelial dysfunction behind CTEPH, and to identify potential novel targets for the prevention and treatment of the disease. Isolated cells from specimens obtained at PEA (CTEPH-EC), were characterized based on morphology, phenotype, and functional analyses (in vitro and in vivo tubule formation, proliferation, apoptosis, and migration). Mitochondrial content, morphology, and dynamics, as well as high-resolution respirometry and oxidative stress, were also studied. CTEPH-EC displayed a hyperproliferative phenotype with an increase expression of adhesion molecules and a decreased apoptosis, eNOS activity, migration capacity and reduced angiogenic capacity in vitro and in vivo compared to healthy endothelial cells. CTEPH-EC presented altered mitochondrial dynamics, increased mitochondrial respiration and an unbalanced production of reactive oxygen species and antioxidants. Our study is the foremost comprehensive investigation of CTEPH-EC. Modulation of redox, mitochondrial homeostasis and adhesion molecule overexpression arise as novel targets and biomarkers in CTEPH.

Characteristics and in-hospital outcomes of patients undergoing balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: a time-trend analysis from the Japanese nationwide registry

BACKGROUND

Balloon pulmonary angioplasty (BPA), a novel technique initially introduced as a treatment for inoperable chronic thromboembolic pulmonary hypertension, is now increasingly being performed in a broader spectrum of patients. Here, we performed a time-trend analysis of the characteristics and in-hospital outcomes of patients who underwent BPA in Japan, using data extracted from nationwide procedure-based registration system.

METHODS

The Japanese Structural Heart Disease (J-SHD) registry was established and sponsored by the Japanese Association of Cardiovascular Intervention and Therapeutics and aims to provide basic statistics on the performance of structural interventions in Japan. J-SHD registers cases from approximately 200 institutions, representing more than 90% of SHD intervention-performing hospitals in the nation. We analysed the registered BPA data elements from January 2015 to December 2018. Successful BPA was defined as a session in which a physician successfully treated all targeted lesions.

RESULTS

There were a total of 2512 BPA sessions; the number of institutions and registered sessions increased from 30 to 50 sites and from 479 to 852 sessions during the study period, respectively. The average age of the patients was 66±13 years, and 72.1% were women. In-hospital death was observed in 0.2%, and the total complications rate was 5.3%. The preoperative and postoperative mean pulmonary artery pressure were 32±11 mm Hg and 30±10 mm Hg, respectively.

CONCLUSION

The number of BPA sessions increased during the study period, with an acceptable in-hospital complication rate.