Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

Non-contrasted computed tomography (NCCT) based chronic thromboembolic pulmonary hypertension (CTEPH) automatic diagnosis using cascaded network with multiple instance learning

Objective.The diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) is challenging due to nonspecific early symptoms, complex diagnostic processes, and small lesion sizes. This study aims to develop an automatic diagnosis method for CTEPH using non-contrasted computed tomography (NCCT) scans, enabling automated diagnosis without precise lesion annotation.Approach.A novel cascade network (CN) with multiple instance learning (CNMIL) framework was developed to improve the diagnosis of CTEPH. This method uses a CN architecture combining two Resnet-18 CNN networks to progressively distinguish between normal and CTEPH cases. Multiple instance learning (MIL) is employed to treat each 3D CT case as a 'bag' of image slices, using attention scoring to identify the most important slices. An attention module helps the model focus on diagnostically relevant regions within each slice. The dataset comprised NCCT scans from 300 subjects, including 117 males and 183 females, with an average age of 52.5 ± 20.9 years, consisting of 132 normal cases and 168 cases of lung diseases, including 88 cases of CTEPH. The CNMIL framework was evaluated using sensitivity, specificity, and the area under the curve (AUC) metrics, and compared with common 3D supervised classification networks and existing CTEPH automatic diagnosis networks.Main results. The CNMIL framework demonstrated high diagnostic performance, achieving an AUC of 0.807, accuracy of 0.833, sensitivity of 0.795, and specificity of 0.849 in distinguishing CTEPH cases. Ablation studies revealed that integrating MIL and the CN significantly enhanced performance, with the model achieving an AUC of 0.978 and perfect sensitivity (1.000) in normal classification. Comparisons with other 3D network architectures confirmed that the integrated model outperformed others, achieving the highest AUC of 0.8419.Significance. The CNMIL network requires no additional scans or annotations, relying solely on NCCT. This approach can improve timely and accurate CTEPH detection, resulting in better patient outcomes.

An exploration into CTEPH medications: Combining natural language processing, embedding learning, in vitro models, and real-world evidence for drug repurposing

BACKGROUND

In the modern era, the growth of scientific literature presents a daunting challenge for researchers to keep informed of advancements across multiple disciplines.

OBJECTIVE

We apply natural language processing (NLP) and embedding learning concepts to design PubDigest, a tool that combs PubMed literature, aiming to pinpoint potential drugs that could be repurposed.

METHODS

Using NLP, especially term associations through word embeddings, we explored unrecognized relationships between drugs and diseases. To illustrate the utility of PubDigest, we focused on chronic thromboembolic pulmonary hypertension (CTEPH), a rare disease with an overall limited number of scientific publications.

RESULTS

Our literature analysis identified key clinical features linked to CTEPH by applying term frequency-inverse document frequency (TF-IDF) scoring, a technique measuring a term's significance in a text corpus. This allowed us to map related diseases. One standout was venous thrombosis (VT), which showed strong semantic links with CTEPH. Looking deeper, we discovered potential repurposing candidates for CTEPH through large-scale neural network-based contextualization of literature and predictive modeling on both the CTEPH and the VT literature corpora to find novel, yet unrecognized associations between the two diseases. Alongside the anti-thrombotic agent caplacizumab, benzofuran derivatives were an intriguing find. In particular, the benzofuran derivative amiodarone displayed potential anti-thrombotic properties in the literature. Our in vitro tests confirmed amiodarone's ability to reduce platelet aggregation significantly by 68% (p = 0.02). However, real-world clinical data indicated that CTEPH patients receiving amiodarone treatment faced a significant 15.9% higher mortality risk (p<0.001).

CONCLUSIONS

While NLP offers an innovative approach to interpreting scientific literature, especially for drug repurposing, it is crucial to combine it with complementary methods like in vitro testing and real-world evidence. Our exploration with benzofuran derivatives and CTEPH underscores this point. Thus, blending NLP with hands-on experiments and real-world clinical data can pave the way for faster and safer drug repurposing approaches, especially for rare diseases like CTEPH.

Tailoring oral anticoagulant treatment in the era of multi-drug therapies for PAH and CTEPH

The use of oral anticoagulants in the management of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) presents distinct therapeutic challenges and benefits. In PAH, the benefits of oral anticoagulation are uncertain, with studies yielding mixed results on their efficacy and safety. Conversely, oral anticoagulants are a cornerstone in the treatment of CTEPH, where their use is consistently recommended to prevent recurrent thromboembolic events. The choice between vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) remains a significant clinical question, as each type presents advantages and potential drawbacks. Furthermore, drug-drug interactions (DDIs) with concomitant PAH and CTEPH treatments complicate anticoagulant management, necessitating careful consideration of individual patient regimens. This review examines the current evidence on oral anticoagulant use in PAH and CTEPH and discusses the implications of DDIs within a context of multi-drug treatments, including targeted drugs in PAH.

Developmental or Procedural Vena Cava Interruption and Venous Thromboembolism: A Review

The inferior vena cava (IVC) and superior vena cava are the main conduits of the systemic venous circulation into the right atrium. Developmental or procedural interruptions of vena cava might predispose to stasis and deep vein thrombosis (DVT) distal to the anomaly and may impact the subsequent rate of pulmonary embolism (PE). This study aimed to review the various etiologies of developmental or procedural vena cava interruption and their impact on venous thromboembolism. A systematic search was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines per each clinical question. For management questions with no high-quality evidence and no mutual agreements between authors, Delphi methods were used. IVC agenesis is the most common form of congenital vena cava interruption, is associated with an increased risk of DVT, and should be suspected in young patients with unexpected extensive bilateral DVT. Surgical techniques for vena cava interruption (ligation, clipping, and plication) to prevent PE have been largely abandoned due to short-term procedural risks and long-term complications, although survivors of prior procedures are occasionally encountered. Vena cava filters are now the most commonly used method of procedural interruption, frequently placed in the infrarenal IVC. The most agreed-upon indication for vena cava filters is for patients with acute venous thromboembolism and coexisting contraindications to anticoagulation. Familiarity with different forms of vena cava interruption and their local and systemic adverse effects is important to minimize complications and thrombotic events.

Chronic thromboembolic pulmonary disease

Chronic thromboembolic pulmonary hypertension is a complication of pulmonary embolism and a treatable cause of pulmonary hypertension. The pathology is a unique combination of mechanical obstruction due to failure of clot resolution, and a variable degree of microvascular disease, that both contribute to pulmonary vascular resistance. Accordingly, multiple treatments have been developed to target the disease components. However, accurate diagnosis is often delayed. Evaluation includes high-quality imaging modalities, necessary for disease confirmation and for appropriate treatment planning. All patients with chronic thromboembolic pulmonary disease, and especially those with pulmonary hypertension, should be referred to expert centres for multidisciplinary team decision on treatment. The first decision remains assessment of operability, and the best improvement in symptoms and survival is achieved by the mechanical therapies, pulmonary endarterectomy and balloon pulmonary angioplasty. With the advances in multimodal therapies, excellent outcomes can be achieved with 3-year survival of >90%.

Sex differences in Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed sequela of acute pulmonary embolism with varied clinical presentation causing significant morbidity among the affected population. There exist important differences in the occurrence, clinical features and diagnosis of CTEPH between men and women, with women carrying a greater predisposition for the disease. Ongoing studies have also pointed out variations among men and women, in the treatment offered and long-term outcomes including mortality. This focused review article highlights important sex-associated differences in multiple aspects of CTEPH including its epidemiology, clinical features, diagnosis, treatment and outcomes as reported in current literature and highlights the need for future research to facilitate a clearer understanding of these differences.

Current surgical management of chronic thromboembolic pulmonary disease

Chronic thromboembolic pulmonary disease (CTEPD) with or without pulmonary hypertension (PH) is an important potential consequence of venous thromboembolic disease. Untreated CTEPD with pulmonary hypertension (CTEPH) is associated with high rates of morbidity and mortality. Several treatment options are now available for patients with CTEPD and CTEPH, including pulmonary endarterectomy (PEA), balloon pulmonary angioplasty, medical therapy or a combination of therapies. Choice of treatment depends on the location of the thromboembolic disease burden, presence and severity of PH and patient factors, including frailty, parenchymal lung disease and other comorbidities. PEA is a complex surgery that can result in excellent outcomes and resolution of disease, but also comes with the risk of serious perioperative complications. This manuscript examines the history of PEA and its place in Australasia, and reports on outcomes from the main Australasian CTEPH expert centre. It provides a summary of up-to-date guidance on how PEA should be utilised in the overall management of these patients and describes opportunities and challenges for the future diagnosis and management of this disease, particularly in the Australasian setting.

Semi-Quantitative Analysis of Lung Perfusion SPECT/CT for Evaluation of Response to Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension

Purpose

We aimed to investigate the response to balloon pulmonary angioplasty (BPA) in chronic thromboembolic pulmonary hypertension (CTEPH) using semi-quantitative analysis of lung perfusion SPECT/CT.

Methods

This is a single-center retrospective study of patients with CTEPH who underwent BPA and pre- and post-BPA lung perfusion SPECT/CT between 2015 and 2022. Segmental defects on SPECT/CT were visually assessed and semi-quantitatively scored as 1 (large defect) or 0.5 (moderate defect) in accordance with modified PIOPED II criteria. The perfusion defect score was defined as (Σ segmental defect scores/18) × 100 (%). Associations between perfusion defect score and hemodynamic or functional parameters including WHO functional class, six-minute walking distance (6MWD), serum B-type natriuretic peptide (BNP), mean arterial pulmonary pressure (mPAP), pulmonary vascular resistance (PVR), and tricuspid regurgitation pressure gradient (TRPG) on echocardiography were statistically analyzed.

Results

A total of 24 consecutive patients were included. The perfusion defect score significantly improved after BPA (median 58.3% vs. 47.2%, P < 0.001), in conjunction with the WHO functional class, 6MWD, serum BNP, mPAP, and TRPG. Perfusion defect scores were significantly correlated with 6MWD (rho = - 0.583, P < 0.001), serum BNP (rho = 0.514, P < 0.001), mPAP (rho = 0.583, P < 0.001), and PVR (rho = 0.575, P < 0.001). The improvement in the perfusion defect score was significantly associated with improvement in mPAP (rho = 0.844, P < 0.001).

Conclusion

Our results suggest that semi-quantitative analysis of lung perfusion SPECT/CT can provide a potential imaging biomarker for monitoring the efficacy of BPA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13139-024-00858-1.

Outcomes of Chronic Thromboembolic Pulmonary Hypertension After Balloon Pulmonary Angioplasty and Pulmonary Endarterectomy

Background

The contemporary outcome of balloon pulmonary angioplasty (BPA) and pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) are unclear.

Objectives

This study aimed to clarify the characteristics and outcomes of CTEPH patients treated with BPA and PEA in Japan.

Methods

Among 1,270 participants enrolled between 2018 and 2023 in the CTEPH AC (Chronic Thromboembolic Pulmonary Hypertension Anticoagulant) registry, a Japanese nationwide CTEPH registry, 369 treatment-naive patients (BPA strategy: n = 313; PEA strategy: n = 56) and 690 on-treatment patients (BPA strategy: n = 561; PEA strategy: n = 129) were classified according to the presence of prior reperfusion therapy. Morbidity and mortality events (all-cause death, rescue mechanical reperfusion therapy, and/or initiation of parenteral pulmonary vasodilators), pulmonary hemodynamics, exercise tolerance, and relevant laboratory test results were evaluated.

Results

The BPA strategy was chosen in older patients than the PEA strategy (mean age, BPA vs PEA: 66.5 ± 12.6 years vs 62.5 ± 11.8 years; P = 0.028). Median follow-up period was 615 (Q1-Q3: 311-997) days in treatment-naive patients and 1,136 (Q1-Q3: 684-1,300) days in on-treatment patients. BPA strategy had as acceptable morbidity and mortality as PEA strategy (5-year morbidity and mortality event rate, BPA vs PEA: 10.2% [95% CI: 5.2%-19.5%] vs 16.1% [95% CI: 4.3%-50.6%] in treatment-naive patients; 9.7% [95% CI: 6.7%-13.8%] vs 6.9% [95% CI: 2.7%-17.3%] in on-treatment patients), with greater improvement of renal function; glomerular filtration rate in propensity score-matched population (difference between change: 4.9 [95% CI: 0.5-9.3] mL/min/1.73 m2; P = 0.030).

Conclusions

BPA strategy was more frequently chosen in older patients compared with PEA strategy and showed acceptable outcomes for efficacy with greater advantage for improvement in renal function. (Multicenter registry of chronic thromboembolic pulmonary hypertension in Japan; UMIN000033784).

Safety Window for Effective Lesion Crossing in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension (CTEPH) is limited by a lack of safe and effective tools for crossing these lesions. We aim to identify a safety window for an intraluminal crossing device in this vascular bed by studying the piercing properties of pulmonary arterial vessel walls and intraluminal CTEPH lesion specimens. As a secondary objective, we also describe the histopathologic features of CTEPH lesions.

Methods

Specimens were procured from 9 patients undergoing pulmonary endarterectomy. The specimens were subsampled and identified grossly as arterial wall or intraluminal CTEPH lesions. The force needed for tissue penetration was measured using a 0.38-mm (0.015-in) diameter probe in an ex vivo experimental model developed in our lab. Concurrent histology was also performed.

Results

The mean force needed to penetrate the arterial wall and intraluminal CTEPH lesions was 1.75 ± 0.10 N (n = 121) and 0.30 ± 0.04 N (n = 56), respectively (P < .001). Histology confirmed the presence of intimal hyperplasia with calcium and hemosiderin deposition in the arterial wall as well as an old, organized thrombus in the lumen.

Conclusions

The pulmonary arterial wall is friable and prone to perforation during instrumentation with workhorse coronary guide wires. However, the results of this study demonstrate that a much lower force is needed for the 0.38-mm (0.015-in) probe to penetrate an intraluminal CTEPH lesion compared to pulmonary arterial intima. This finding suggests the existence of a safety window for lesion-crossing devices, enabling effective balloon pulmonary angioplasty.

Chronic Thromboembolic Pulmonary Hypertension: the therapeutic assessment

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is a severe and complex condition that evolves from unresolved pulmonary embolism, leading to fibrotic obstruction of pulmonary arteries, pulmonary hypertension, and potential right heart failure. The cornerstone of CTEPH management lies in a multifaceted therapeutic approach tailored to individual patient profiles, reflecting the disease's heterogeneity. This review delves into the current therapeutic strategies for CTEPH, including surgical pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA), and targeted pharmacological treatments such as PDE5 inhibitors, endothelin receptor antagonists, sGC stimulators, and prostanoids. Lifelong anticoagulation is also highlighted as a preventive strategy against recurrent thromboembolism. Special emphasis is placed on the interdisciplinary nature of CTEPH care, necessitating collaboration among PEA surgeons, BPA interventionists, PH specialists, and thoracic radiologists to ensure comprehensive treatment planning and execution. The review underscores the importance of selecting an appropriate treatment modality based on the patient's specific disease characteristics and the evolving landscape of CTEPH treatment, aiming to improve patient outcomes through integrated care strategies.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary disease without pulmonary hypertension

Balloon pulmonary angioplasty (BPA) is beneficial for patients with chronic thromboembolic pulmonary disease (CTEPD) with pulmonary hypertension (PH). However, the clinical benefit of BPA for the patients with CTEPD without PH remains unknown. In this study, we aimed to evaluate the efficacy, safety, and long-term outcomes of BPA in patients with CTEPD without PH. We retrospectively analyzed the data from 84 CTEPD patients with mean pulmonary artery pressure (mPAP) < 25 mmHg and 39 CTEPD patients with mPAP ≤ 20 mmHg (without PH). Among the 39 patients with CTEPD without PH, 14 underwent BPA (BPA-treated group), and the remaining 25 received no treatment (untreated group). In the patients with CTEPD without PH, BPA led to improvements in symptoms, pulmonary vascular resistance (3.6 ± 1.6 to 2.6 ± 1.1 Wood units, p < 0.001), peak oxygen consumption (16.1 ± 4.0 to 18.8 ± 4.3 mL/kg/min, p = 0.033), minute ventilation versus carbon dioxide production slope (41.4 ± 12.2 to 35.1 ± 6.7, p = 0.026), and mPAP/cardiac output slope (7.0 ± 2.6 to 4.4 ± 2.0 mmHg/L/min, p = 0.004) and facilitated the discontinuation of home oxygenation therapy, with no serious complications. Kaplan-Meier analysis showed no significant difference in all-cause mortality between the untreated and BPA-treated groups. BPA may be a safe treatment option for the patients with CTEPD without PH that can alleviate symptoms, improve exercise capacity, and facilitate weaning from home oxygen therapy. Further prospective randomized trials are needed to confirm these findings.

Balloon pulmonary angioplasty for proximal chronic thromboembolic pulmonary hypertension in patients ineligible for pulmonary endarterectomy

Balloon pulmonary angioplasty (BPA) to treat chronic thromboembolic pulmonary hypertension (CTEPH) is generally reserved for distal obstruction precluding pulmonary endarterectomy (PEA) but can be used in patients with proximal disease who are at high surgical risk or refuse surgery. This single-center retrospective study compared BPA efficacy in patients with proximal versus distal CTEPH. Of the 478 patients, 36 had proximal disease, follow-up was 11.6 months and mean number of BPA 6. After BPA, PVR, and mean pulmonary artery pressure decreased significantly in the proximal and distal groups (from 6.5 to 4.0 WU and 39 to 31 mmHg and from 7.6 to 3.8 WU and 44 to 31 mmHg, respectively, p < 0.001 for all comparisons). NYHA class also improved significantly in both groups, from 3 to 2, whereas the 6-min walk distance, cardiac output, and serum NT pro-BNP showed significant improvements only in the distal group. Thus, when PEA for CTEPH is technically feasible but not performed due to severe comorbidities or patient refusal, BPA can produce significant hemodynamic improvements, albeit less marked than in patients with distal disease. Better patient selection to BPA might improve outcomes in patients with proximal disease who are ineligible for PEA.

Chronic thromboembolic pulmonary hypertension: A comprehensive review of pathogenesis, diagnosis, and treatment strategies

Chronic thromboembolic pulmonary hypertension (CTEPH) is part of group 4 of the pulmonary hypertension (PH) classification and generally affects more than a third of patients referred to PH centers. It is a three-compartment disease involving proximal (lobar-to-segmental) and distal (subsegmental) pulmonary arteries that are obstructed by persistent fibrothrombotic material, and precapillary pulmonary arteries that can be affected as in pulmonary arterial hypertension. It is a rare complication of pulmonary embolism (PE), with an incidence of around 3% in PE survivors. The observed incidence of CTEPH in the general population is around six cases per million but could be three times higher than this, as estimated from PE incidence. However, a previous venous thromboembolic episode is not always documented. With advances in multimodality imaging and therapeutic management, survival for CTEPH has improved for both operable and inoperable patients. Advanced imaging with pulmonary angiography helps distinguish proximal from distal obstructive disease. However, right heart catheterization is of utmost importance to establish the diagnosis and hemodynamic severity of PH. The therapeutic strategy relies on a stepwise approach, starting with an operability assessment. Pulmonary endarterectomy (PEA), also known as pulmonary thromboendarterectomy, is the first-line treatment for operable patients. Growing experience and advances in surgical technique have enabled expansion of the distal limits of PEA and significant improvements in perioperative and mid- to long-term mortality. In patients who are inoperable or who have persistent/recurrent PH after PEA, medical therapy and/or balloon pulmonary angioplasty (BPA) are effective treatment options with favorable outcomes that are increasingly used. All treatment decisions should be made with a multidisciplinary team that includes a PEA surgeon, a BPA expert, and a chest radiologist.

Shared and Distinct Genomics of Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Embolism

Rationale: Chronic thromboembolic pulmonary hypertension involves the formation and nonresolution of thrombus, dysregulated inflammation, angiogenesis, and the development of a small-vessel vasculopathy. Objectives: We aimed to establish the genetic basis of chronic thromboembolic pulmonary hypertension to gain insight into its pathophysiological contributors. Methods: We conducted a genome-wide association study on 1,907 European cases and 10,363 European control subjects. We coanalyzed our results with existing results from genome-wide association studies on deep vein thrombosis, pulmonary embolism, and idiopathic pulmonary arterial hypertension. Measurements and Main Results: Our primary association study revealed genetic associations at the ABO, FGG, F11, MYH7B, and HLA-DRA loci. Through our coanalysis, we demonstrate further associations with chronic thromboembolic pulmonary hypertension at the F2, TSPAN15, SLC44A2, and F5 loci but find no statistically significant associations shared with idiopathic pulmonary arterial hypertension. Conclusions: Chronic thromboembolic pulmonary hypertension is a partially heritable polygenic disease, with related though distinct genetic associations with pulmonary embolism and deep vein thrombosis.

Novel insights into the potential applications of stem cells in pulmonary hypertension therapy

Pulmonary hypertension (PH) refers to a group of deadly lung diseases characterized by vascular lesions in the microvasculature and a progressive increase in pulmonary vascular resistance. The prevalence of PH has increased over time. Currently, the treatment options available for PH patients have limited efficacy, and none of them can fundamentally reverse pulmonary vascular remodeling. Stem cells represent an ideal seed with proven efficacy in clinical studies focusing on liver, cardiovascular, and nerve diseases. Since the potential therapeutic effect of mesenchymal stem cells (MSCs) on PH was first reported in 2006, many studies have demonstrated the efficacy of stem cells in PH animal models and suggested that stem cells can help slow the deterioration of lung tissue. Existing PH treatment studies basically focus on the paracrine action of stem cells, including protein regulation, exosome pathway, and cell signaling; however, the specific mechanisms have not yet been clarified. Apoptotic and afunctional pulmonary microvascular endothelial cells (PMVECs) and alveolar epithelial cells (AECs) are two fundamental promoters of PH although they have not been extensively studied by researchers. This review mainly focuses on the supportive communication and interaction between PMVECs and AECs as well as the potential restorative effect of stem cells on their injury. In the future, more studies are needed to prove these effects and explore more radical cures for PH.

Notch ratio in pulmonary flow predicts long-term survival after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension

BACKGROUND

Assessment of the pattern of the RV outflow tract Doppler provides insights into the hemodynamics of chronic thromboembolic pulmonary hypertension (CTEPH). We studied whether pre-operative assessment of timing of the pulmonary flow systolic notch by Doppler echocardiography is associated with long-term survival after pulmonary endarterectomy (PEA) for CTEPH.

METHODS

Fifty-nine out of 61 consecutive CETPH patients (mean age 53 ± 14 years, 34% male) whom underwent PEA between June 2002 and June 2005 were studied. Clinical, echocardiographic and hemodynamic variables were assessed pre-operatively and repeat echocardiography was performed 3 months after PEA. Notch ratio (NR) was assessed with pulsed Doppler and calculated as the time from onset of pulmonary flow until notch divided by the time from notch until end of pulmonary flow. Long-term follow-up was obtained between May 2021 and February 2022.

RESULTS

Pre-operative mean pulmonary artery pressure (mPAP) was 45 ± 15 mmHg and pulmonary vascular resistance (PVR) was 646 ± 454 dynes.s.cm-5. Echocardiography before PEA showed that 7 patients had no notch, 33 had a NR < 1.0 and 19 had a NR > 1.0. Three months after PEA, echocardiography revealed a significant decrease in sPAP in long-term survivors with a NR < 1.0 and a NR > 1.0, while a significant increase in TAPSE/sPAP was only observed in the NR < 1.0 group. Mean long-term clinical follow-up was 14 ± 6 years. NR was significantly different between survivors and non-survivors (0.73 ± 0.25 vs. 1.1 ± 0.44, p < 0.001) but no significant differences were observed in mPAP or PVR. Long-term survival at 14 years was significantly better in patients with a NR < 1.0 compared to patients with a NR > 1.0 (83% vs. 37%, p =  < 0.001).

CONCLUSION

Pre-operative assessment of NR is a predictor of long-term survival in CTEPH patients undergoing PEA, with low mortality risk in patients with NR < 1.0. Long-term survivors with a NR < 1.0 and NR > 1.0 had a significant decrease in sPAP after PEA. However, the TAPSE/sPAP only significantly increased in the NR < 1.0 group. In the NR < 1.0 group, the 6-min walk test increased significantly between pre-operative and at 1-year post-operative follow-up. NR is a simple echocardiographic parameter that can be used in clinical decision-making for PEA.

Post-pulmonary embolism syndrome: A reminder for clinicians

Acute pulmonary embolism (APE) is one of the leading causes of cardiovascular emergencies and the third leading cause of death. Although efforts focus on treating the acute event, patients who survive APE may develop long-term sequelae. Research reveals that approximately half of patients who have suffered an APE do not regain their previous level of function and experience a reduction in their quality of life for several years after the episode. Acute pulmonary embolism can be classified according to the risk of short-term mortality, with most mortality and morbidity concentrated in high-risk and intermediate-risk cases. The first-line treatment for APE is systemic anticoagulation. However, identifying and more aggressively treating people with intermediate to high risk, who have a more favorable risk profile for reperfusion treatments, could reduce short-term mortality and mitigate post-pulmonary embolism syndrome (PPES). Post-pulmonary embolism syndrome refers to a variety of persistent symptoms and functional limitations that occur after an APE. The presence of persistent dyspnea, functional limitations, and/or decreased quality of life after an APE has been recently termed "PPES," although this entity encompasses different manifestations. The most severe cause of persistent dyspnea is chronic thromboembolic pulmonary hypertension, where increased pulmonary artery pressure is due to the fibrotic organization of unresolved APE. Post-PE Syndrome is not always systematically addressed in management guidelines, and its prevalence may be underestimated. More research is needed to fully understand its causes and risk factors. Interventions such as cardiopulmonary rehabilitation have been suggested to improve the quality of life of patients with PPES. A comprehensive, evidence-based approach is essential to effectively prevent and manage PPES and improve the long-term outcomes and well-being of affected patients.

Chronic Thromboembolic Pulmonary Hypertension: Clinical and Imaging Evaluation

Chronic thromboembolic pulmonary hypertension (CTEPH) is a complication of pulmonary embolism and is an important cause of pulmonary hypertension. As a clinical entity, it is frequently underdiagnosed with prolonged diagnostic delays. This study reviews the clinical and radiographic findings associated with CTEPH to improve awareness and recognition. Strengths and limitations of multiple imaging modalities are reviewed. Accompanying images are provided to supplement the text and provide examples of important findings for the reader.

Preexisting Chronic Thromboembolic Pulmonary Hypertension in Acute Pulmonary Embolism? A Case Report and Discussion

A 61-year-old male presented with New York Heart Association class II breathlessness. Three years earlier, he had presented with a swollen leg, had received a diagnosis of deep vein thrombosis on ultrasound and of low-risk acute pulmonary embolism, and had been discharged on a direct oral anticoagulant after 8 hours. The patient also had a history of thyroidectomy and was on levothyroxine substitution. The case illustrates a patient with acute pulmonary embolism who developed chronic thrombotic pulmonary vascular lesions within 3 years after acute pulmonary embolism in the presence of typical risk factors.

Imaging of chronic thromboembolic pulmonary hypertension before, during and after balloon pulmonary angioplasty

Balloon pulmonary angioplasty (BPA) has recently been elevated as a class I recommendation for the treatment of inoperable or residual chronic thromboembolic pulmonary hypertension (CTEPH). Proper patient selection, procedural safety, and post-procedural evaluation are crucial in the management of these patients, with imaging work-up playing a pivotal role. Understanding the diagnostic and therapeutic imaging algorithms of CTEPH, the imaging features of patients amenable to BPA, all imaging findings observed during and immediately after the procedure and the changes observed during the follow-up is crucial for all interventional radiologists involved in the care of patients with CTEPH. This article illustrates the imaging work-up of patients with CTEPH amenable to BPA, the imaging findings observed before, during and after BPA, and provides a detailed description of all imaging modalities available for CTEPH evaluation.

New-onset postoperative atrial fibrillation after pulmonary endarterectomy is associated with adverse outcomes

Background

New-onset postoperative atrial fibrillation (POAF) is a common complication after pulmonary thromboendarterectomy (PEA), yet the risk factors and their impact on prognosis remain poorly understood. This study aims to investigate the risk factors associated with new-onset POAF after PEA and elucidate its underlying connection with adverse postoperative outcomes.

Methods

A retrospective analysis included 129 consecutive chronic thromboembolic pulmonary hypertension (CTEPH) patients and 16 sarcoma patients undergoing PEA. Univariate and multivariate analyses were conducted to examine the potential effects of preoperative and intraoperative variables on new-onset POAF following PEA. Propensity score matching (PSM) was then employed to adjust for confounding factors.

Results

Binary logistic regression revealed that age (odds ratio [OR] = 1.041, 95% confidence interval [CI] = 1.008-1.075, p = 0.014) and left atrial diameter[LAD] (OR = 1.105, 95% CI = 1.025-1.191, p = 0.009) were independent risk factors for new-onset POAF after PEA. The receiver operating characteristic (ROC) curve indicated that the predictive abilities of age and LAD for new-onset POAF were 0.652 and 0.684, respectively. Patients with new-onset POAF, compared with those without, exhibited a higher incidence of adverse outcomes (in-hospital mortality, acute heart failure, acute kidney insufficiency, reperfusion pulmonary edema). Propensity score matching (PSM) analyses confirmed the results.

Conclusion

Advanced age and LAD independently contribute to the risk of new-onset POAF after PEA. Patients with new-onset POAF are more prone to adverse outcomes. Therefore, heightened vigilance and careful monitoring of POAF after PEA are warranted.

Balloon Pulmonary Angioplasty for the Treatment of Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension is a rare form of pulmonary hypertension in patients who have evidence of chronic thromboembolic occlusion of the pulmonary vasculature. Historically, surgical pulmonary thromboendarterectomy has been the treatment of choice. However, with up to 40% of patients deemed inoperable, balloon pulmonary angioplasty has emerged as an additional treatment strategy. Balloon pulmonary angioplasty is a complementary strategy alongside surgical pulmonary thromboendarterectomy and offers the opportunity for pulmonary revascularization in patients who have more distal disease, higher comorbidities, or residual obstruction following operative intervention. This review examines the history of balloon pulmonary angioplasty, highlights its effectiveness, discusses important complications and risk reduction strategies, and emphasizes the importance of centers forming a multidisciplinary team of providers to manage the complexity of patients with chronic thromboembolic pulmonary hypertension.

Comorbidities, Treatment and Survival Rates of Chronic Thromboembolic Pulmonary Hypertension in a Regional Centre

Background/Objectives: Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by a multitude of underlying causes, treatment modalities and prognostic outcomes. Our aim was to evaluate the underlying causes, comorbidities and survival rates of CTEPH patients. Methods: A retrospective analysis was conducted regarding the evolution of CTEPH patients confirmed by right heart catheterization under treatment with specific vasodilator medication in our centre between 2008 and 2023. Results: We treated 14 CTEPH patients, 78.57% female, 52.79 ± 13.64 years at inclusion, representing 11.29% of our pulmonary arterial hypertension registry. Initially, the distribution of patients' NYHA class was II-14.28%, III-71.42% and IV-14.28%. In total, 71.42% of these patients were technically operable due to the central location of the thrombus, but 42.85% presented severe comorbidities and 28.57% refused the surgery or it was financially inaccessible. Only four patients were operated on by pulmonary endarterectomy (PEA). Unfortunately, all the post-PEA patients had persistent pulmonary hypertension and had to continue vasodilator treatment. Overall, 64.28% of patients had monotherapy, 21.42% double therapy and 14.28% triple therapy. Regarding underlying causes and comorbidities, we found the following incidences: 78.57% chronic venous insufficiency, 42.85% obesity, 35.71% thyroid disease, hypertension and hyperuricemia, 21.42% thrombophilia and ischemic heart disease, 14.28% atrial fibrillation, vasculitis and lung disease, and 14.28% neoplastic history and diabetes. Seven patients died (50%), six of whom were unoperated and one of whom was lost (abandoned the program). The survival rates at 1, 3, 5 and 7 years for unoperated patients were 100%, 58.3%, 29.2% and 29.2% versus 100%, 75%, 75% and 75% in post-PEA patients. Conclusions: CTEPH, marked by delayed diagnosis, multiple comorbidities and limited intervention options, requires proactive screening and comprehensive multimodal therapies, including PEA, to improve survival rates.

Chronic thromboembolic pulmonary hypertension and balloon pulmonary angioplasty - Where are we in 2024?

Pulmonary endarterectomy (PEA) is the first-line treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, some patients with CTEPH are considered inoperable, and in the last decade, balloon pulmonary angioplasty (BPA) has emerged as a viable therapeutic option for these patients with prohibitive surgical risk or recurrent pulmonary hypertension following PEA. Numerous international centers have increased their procedural volume of BPA and have reported improvements in pulmonary hemodynamics, patient functional class and right ventricular function. Randomized controlled trials have also demonstrated similar findings. Recent refinements in procedural technique, increased operator experience and advancements in procedural technology have facilitated marked reduction in the risk of complications following BPA. Current guidelines recommend BPA for patients with inoperable CTEPH and persistent pulmonary hypertension following PEA. The pulmonary arterial endothelium plays a vital role in the pathophysiologic development and progression of CTEPH.

Usefulness of risk assessment tools in predicting hemodynamic outcome after balloon pulmonary angioplasty: a comparative analysis

OBJECTIVES

Several parameters of widely used risk assessment tools for pulmonary arterial hypertension (PAH) have been linked to hemodynamic outcomes of balloon pulmonary angioplasty (BPA). Therefore, we aimed to determine whether these risk assessment tools could be used to predict hemodynamic outcomes following BPA.

METHODS

In this retrospective study, we included 139 patients with chronic thromboembolic pulmonary hypertension who had undergone BPA at Center for Pulmonary Vascular Diseases, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College (Beijing, China). We compared the accuracies of seven well-validated risk assessment tools for predicting hemodynamic outcomes following BPA. A favorable hemodynamic outcome was defined as a mean pulmonary arterial pressure < 30 mmHg at follow-up.

RESULTS

The baseline risk profiles varied significantly among the risk assessment tools. The US Registry to Evaluate Early and Long-Term PAH Disease Management risk scales and the French risk assessment tools rated most patients as high-risk, while the Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (COMPERA) series and laboratory examination-based risk scales categorized most patients as having intermediate-risk profile. COMPERA 2.0 (4-strata) exhibited the highest predictive power among all risk stratifications. Noninvasive risk stratification (COMPERA 2.0 [3-strata]) showed a comparable predictive ability to that of invasive risk stratification (COMPERA 1.0) (area under the curve 0.649 vs. 0.648). Moreover, incorporating diffusing capacity of the lungs for carbon monoxide and tricuspid regurgitation velocity into COMPERA 2.0 (4-strata) further enhanced its predictive power (net reclassification index 0.153, 95% confidence interval 0.009-0.298, p = 0.038). Additionally, this refined COMPERA version had a high calibration accuracy (slope 0.96).

CONCLUSION

Although the risk strata distribution varied among different risk assessment tools, the proportion of patients achieving favorable hemodynamics decreased with the escalation of risk stratification in most models. The well-validated risk assessment tools for PAH could also predict hemodynamic outcomes following BPA, and the refined COMPERA 2.0 model exhibited the highest predictive ability among these. Applying risk assessment tools before BPA can facilitate early identification of patients in need of closer monitoring and more intensive interventions, contributing to a better prognosis after BPA.

Electrocardiographic Changes after Endovascular Mechanical Thrombectomy in a Patient with Pulmonary Embolism-A Case Report and Literature Review

Background: Pulmonary embolism (PE) is a common disease with an annual incidence of about 1/1000 persons. About every sixth patient dies within the first 30 days after diagnosis. The electrocardiogram (ECG) is one of the first diagnostic tests performed, and is able to confirm the suspicion of PE with typical electrocardiographic signs. Some ECG signs and their regression are also prognostically relevant. Endovascular mechanical thrombectomy is one option for PE treatment, and aims to relieve right heart strain immediately. The first studies on endovascular mechanical thrombectomy using a dedicated device (FlowTriever System, Inari Medical, Irvine, CA, USA) yielded promising results. Methods: In the following, we report the case of a 66-year-old male patient who presented with New York Heart Association III dyspnea in our emergency department. Among typical clinical and laboratory results, he displayed very impressive electrocardiographic and radiological findings at the time of PE diagnosis. Results: After endovascular mechanical thrombectomy, the patient's complaints and pulmonary hemodynamics improved remarkably. In contrast, the ECG worsened paradoxically 18 h after intervention. Nevertheless, control echocardiography 4 days after the intervention no longer showed any signs of right heart strain, and dyspnea had disappeared completely. At a 4-month follow-up visit, the patient presented as completely symptom-free with a high quality of life. His ECG and echocardiography were normal and excluded recurrent right heart strain. Conclusions: Overall, the patient benefitted remarkably from endovascular mechanical thrombectomy, resulting in an almost complete resolution of electrocardiographic PE signs at the 4-month follow-up after exhibiting multiple typical electrocardiographic PE signs at time of diagnosis and initial electrocardiographic worsening 18 h post successful intervention.

Can Routine Investigation for Occult Pulmonary Embolism Be Justified in Patients with Deep Vein Thrombosis?

Purpose

This study aims to investigate whether routine screening for silent pulmonary embolism (PE) can be justified in patients with deep vein thrombosis (DVT).

Materials and Methods

We retrospectively analyzed the medical records of 201 patients with lower-extremity DVT admitted to the vascular surgery department of a single tertiary university center between 2019 and 2023. All patients underwent clinical evaluation, basic laboratory exams, a whole-leg colored duplex ultrasound, and a computed tomography pulmonary angiography (CTPA), to screen for an occult, underlying PE.

Results

The overall incidence of silent PE was 48.8%. The median admission D-dimer level was significantly higher in patients with silent PE than in those without PE (9.60 vs. 5.51 mg/L, P=0.001). A D-dimer value ≥5.14 mg/L was discriminant for predicting silent PE, with a sensitivity of 68.2% and a specificity of 59.3%. Silent PE was significantly more common on the right side, with the embolus located at the main pulmonary, lobar, segmental, and subsegmental arteries in 29.6%, 32.7%, 20.4%, and 17.3%, respectively. A higher incidence of occult PE was observed in patients with iliofemoral DVT (P=0.037), particularly when the thrombus extended to the inferior vena cava (P=0.003). Moreover, iliofemoral DVT was associated with a larger size and a more proximal location of the embolus (P=0.041). Multivariate logistic regression showed that male sex (odds ratio [OR]=2.46, 95% confidence interval [CI]: 1.39-3.53; P=0.026), cancer (OR=2.76, 95% CI: 1.45-4.07; P=0.017), previous venous thromboembolism (VTE) history (OR=2.67, 95% CI: 1.33-4.01; P=0.022), D-dimer value ≥5.14 mg/L (OR=2.24, 95% CI: 1.10-3.38; P=0.033), iliofemoral DVT (OR=2.13, 95% CI: 1.19-3.07; P=0.041), and thrombus extension to the IVC (OR=2.95, 95% CI: 1.43-4.47; P=0.009) served as independent predictors for silent PE.

Conclusion

A high incidence of silent PE was observed in patients with lower-extremity DVT. Screening of patients with DVT who have the aforementioned predictive risk factors using CTPA for silent PE may be needed and justified for the efficient management of VTE and its long-term complications.

A systematic review of artificial intelligence tools for chronic pulmonary embolism on CT pulmonary angiography

Background

Chronic pulmonary embolism (PE) may result in pulmonary hypertension (CTEPH). Automated CT pulmonary angiography (CTPA) interpretation using artificial intelligence (AI) tools has the potential for improving diagnostic accuracy, reducing delays to diagnosis and yielding novel information of clinical value in CTEPH. This systematic review aimed to identify and appraise existing studies presenting AI tools for CTPA in the context of chronic PE and CTEPH.

Methods

MEDLINE and EMBASE databases were searched on 11 September 2023. Journal publications presenting AI tools for CTPA in patients with chronic PE or CTEPH were eligible for inclusion. Information about model design, training and testing was extracted. Study quality was assessed using compliance with the Checklist for Artificial Intelligence in Medical Imaging (CLAIM).

Results

Five studies were eligible for inclusion, all of which presented deep learning AI models to evaluate PE. First study evaluated the lung parenchymal changes in chronic PE and two studies used an AI model to classify PE, with none directly assessing the pulmonary arteries. In addition, a separate study developed a CNN tool to distinguish chronic PE using 2D maximum intensity projection reconstructions. While another study assessed a novel automated approach to quantify hypoperfusion to help in the severity assessment of CTEPH. While descriptions of model design and training were reliable, descriptions of the datasets used in training and testing were more inconsistent.

Conclusion

In contrast to AI tools for evaluation of acute PE, there has been limited investigation of AI-based approaches to characterising chronic PE and CTEPH on CTPA. Existing studies are limited by inconsistent reporting of the data used to train and test their models. This systematic review highlights an area of potential expansion for the field of AI in medical image interpretation.There is limited knowledge of A systematic review of artificial intelligence tools for chronic pulmonary embolism in CT. This systematic review provides an assessment on research that examined deep learning algorithms in detecting CTEPH on CTPA images, the number of studies assessing the utility of deep learning on CTPA in CTEPH was unclear and should be highlighted.

Status and Future Directions for Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Disease With and Without Pulmonary Hypertension: A Scientific Statement From the American Heart Association

Balloon pulmonary angioplasty continues to gain traction as a treatment option for patients with chronic thromboembolic pulmonary disease with and without pulmonary hypertension. Recent European Society of Cardiology guidelines on pulmonary hypertension now give balloon pulmonary angioplasty a Class 1 recommendation for inoperable and residual chronic thromboembolic pulmonary hypertension. Not surprisingly, chronic thromboembolic pulmonary hypertension centers are rapidly initiating balloon pulmonary angioplasty programs. However, we need a comprehensive, expert consensus document outlining critical concepts, including identifying necessary personnel and expertise, criteria for patient selection, and a standardized approach to preprocedural planning and establishing criteria for evaluating procedural efficacy and safety. Given this lack of standards, the balloon pulmonary angioplasty skill set is learned through peer-to-peer contact and training. This document is a state-of-the-art, comprehensive statement from key thought leaders to address this gap in the current clinical practice of balloon pulmonary angioplasty. We summarize the current status of the procedure and provide a consensus opinion on the role of balloon pulmonary angioplasty in the overall care of patients with chronic thromboembolic pulmonary disease with and without pulmonary hypertension. We also identify knowledge gaps, provide guidance for new centers interested in initiating balloon pulmonary angioplasty programs, and highlight future directions and research needs for this emerging therapy.

Nationwide trends of balloon pulmonary angioplasty and pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension (2012-2019)

Chronic thromboembolic pulmonary hypertension (CTEPH) is a sequela of a pulmonary embolus that occurs in approximately 1%-3% of patients. Pulmonary thromboendoarterectomy (PTE) can be a curative procedure, but balloon pulmonary angioplasty (BPA) has emerged as an option for poor surgical candidates. We used the National Inpatient Sample to query patients who underwent PTE or BPA between 2012 and 2019 with CTEPH. The primary outcome was a composite of in-hospital mortality, myocardial infarction, stroke, tracheostomy, and prolonged mechanical ventilation. Outcomes were compared between low- and high-volume centers, defined as 5 and 10 procedures per year for BPA and PTE, respectively. During our study period, 870 BPA and 2395 PTE were performed. There was a 328% relative increase in the number of PTE performed during the study period. Adverse events for BPA were rare. There was an increase in the primary composite outcome for low-volume centers compared to high-volume centers for PTE (24.4% vs. 12.1%, p = 0.003). Patients with hospitalizations for PTE in low-volume centers were more likely to have prolonged mechanical ventilation (20.0%% vs. 7.2%, p < 0.001) and tracheostomy (7.8% vs. 2.6%, p = 0.017). In summary, PTE rates have been rising over the past 10 years, while BPA rates have remained stable. While adverse outcomes are rare for BPA, patients with hospitalizations at low-volume centers for PTE were more likely to have adverse outcomes. For patients undergoing treatment of CTEPH with BPA or PTE, referral to high-volume centers with multidisciplinary teams should be encouraged for optimal outcomes.

How Would I Treat My Own Chronic Thromboembolic Pulmonary Hypertension in the Perioperative Period?

Chronic thromboembolic pulmonary hypertension (CTEPH) results from an incomplete resolution of acute pulmonary embolism, leading to occlusive organized thrombi, vascular remodeling, and associated microvasculopathy with pulmonary hypertension (PH). A definitive CTEPH diagnosis requires PH confirmation by right-heart catheterization and evidence of chronic thromboembolic pulmonary disease on imaging studies. Surgical removal of the organized fibrotic material by pulmonary endarterectomy (PEA) under deep hypothermic circulatory arrest represents the treatment of choice. One-third of patients with CTEPH are not deemed suitable for surgical treatment, and medical therapy or interventional balloon pulmonary angioplasty presents alternative treatment options. Pulmonary endarterectomy in patients with technically operable disease significantly improves symptoms, functional capacity, hemodynamics, and quality of life. Perioperative mortality is <2.5% in expert centers where a CTEPH multidisciplinary team optimizes patient selection and ensures the best preoperative optimization according to individualized risk assessment. Despite adequate pulmonary artery clearance, patients might be prone to perioperative complications, such as right ventricular maladaptation, airway bleeding, or pulmonary reperfusion injury. These complications can be treated conventionally, but extracorporeal membrane oxygenation has been included in their management recently. Patients with residual PH post-PEA should be considered for medical or percutaneous interventional therapy.

Pulmonary vascular disease, environmental pollution, and climate change

Pollution and climate change constitute a combined, grave and pervasive threat to humans and to the life-support systems on which they depend. Evidence shows a strong association between pollution and climate change on cardiovascular and respiratory diseases, and pulmonary vascular disease (PVD) is no exception. An increasing number of studies has documented the impact of environmental pollution and extreme temperatures on pulmonary circulation and the right heart, on the severity and outcomes of patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (PH), on the incidence of pulmonary embolism, and the prevalence and severity of diseases associated with PH. Furthermore, the downstream consequences of climate change impair health care systems' accessibility, which could pose unique obstacles in the case of PVD patients, who require a complex and sophisticated network of health interventions. Patients, caretakers and health care professionals should thus be included in the design of policies aimed at adaptation to and mitigation of current challenges, and prevention of further climate change. The purpose of this review is to summarize the available evidence concerning the impact of environmental pollution and climate change on the pulmonary circulation, and to propose measures at the individual, healthcare and community levels directed at protecting patients with PVD.

Macitentan for the treatment of inoperable chronic thromboembolic pulmonary hypertension (MERIT-1): results from the multicentre, phase 2, randomised, double-blind, placebo-controlled study

BACKGROUND

Macitentan is beneficial for long-term treatment of pulmonary arterial hypertension. The microvasculopathy of chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary arterial hypertension are similar.

METHODS

The phase 2, double-blind, randomised, placebo-controlled MERIT-1 trial assessed macitentan in 80 patients with CTEPH adjudicated as inoperable. Patients identified as WHO functional class II-IV with a pulmonary vascular resistance (PVR) of at least 400 dyn·s/cm5 and a walk distance of 150-450 m in 6 min were randomly assigned (1:1), via an interactive voice/web response system, to receive oral macitentan (10 mg once a day) or placebo. Treatment with phosphodiesterase type-5 inhibitors and oral or inhaled prostanoids was permitted for WHO functional class III/IV patients. The primary endpoint was resting PVR at week 16, expressed as percentage of PVR measured at baseline. Analyses were done in all patients who were randomly assigned to treatment; safety analyses were done in all patients who received at least one dose of the study drug. This study is registered with ClinicalTrials.gov, number NCT02021292.

FINDINGS

Between April 3, 2014, and March 17, 2016, we screened 186 patients for eligibility at 48 hospitals across 20 countries. Of these, 80 patients in 36 hospitals were randomly assigned to treatment (40 patients to macitentan, 40 patients to placebo). At week 16, geometric mean PVR decreased to 71·5% of baseline in the macitentan group and to 87·6% in the placebo group (geometric means ratio 0·81, 95% CI 0·70-0·95, p=0·0098). The most common adverse events in the macitentan group were peripheral oedema (9 [23%] of 40 patients) and decreased haemoglobin (6 [15%]).

INTERPRETATION

In MERIT-1, macitentan significantly improved PVR in patients with inoperable CTEPH and was well tolerated.

FUNDING

Actelion Pharmaceuticals Ltd.

Flow Grade-Based Success Rates, Complication Rates, and Balloon Pulmonary Angioplasty Patency for Total Occlusions

BACKGROUND

The number of successfully recanalized total occlusions affects hemodynamic improvement after balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to clarify the current efficacy, patency, and success rate of BPA for total occlusions.

METHODS

Between April 2016 and August 2021, 178 BPAs were performed in 100 patients with CTEPH and total occlusions. The primary success and subsequent patency rates immediately before the second BPA procedure (follow-up) were compared between the segmental and subsegmental groups, based on the flow grade, which was defined as follows: 0, no reperfusion; 1, minimal reperfusion; 2, partial reperfusion; and 3, complete reperfusion.

RESULTS

Total occlusions were mainly located in the right lung (70%) and lower lobes (48%). The primary success rate was 88%, with significant improvements in oxygenation, hemodynamic parameters, and 6-minute walk test. The primary flow grade did not differ between groups. However, the proportion of lesions with a flow grade of 2 or 3 at follow-up was significantly higher in the subsegmental group than in the segmental group (84% vs 45%, respectively; P < 0.01). In multivariate analysis, flow grade in the acute phase (odds ratio [OR], 46.9; 95% confidence interval [CI], 12.54-176.78; P < 0.01) and subsegmental lesions (OR, 13.8; 95% CI, 3.24-58.94; P < 0.01) were independently associated with better patency (flow grade of 2 or 3) at follow-up.

CONCLUSIONS

Total occlusions can be safely and effectively treated with BPA. BPA for total occlusions may be preferable for subsegmental over segmental lesions.

Efficacy of balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension patients with pulmonary comorbidity

Background

Balloon pulmonary angioplasty (BPA) is an established treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH), but its efficacy in CTEPH patients with a pulmonary comorbidity has not been well-studied. Here, we compared post-BPA outcomes between CTEPH patients with and without chronic pulmonary disease at baseline and analyzed predictors of BPA success.

Methods

From August 2017 to October 2022, 62 patients with inoperable CTEPH who underwent BPA were consecutively enrolled and grouped based on the presence of a pulmonary comorbidity at baseline. All patients underwent transthoracic echocardiography, pulmonary function tests, and right heart catheterization. Pre- and post-BPA data were evaluated to identify factors that influence the success of BPA.

Results

Among the 62 CTEPH patients, BPA was considered successful in 50 patients and unsuccessful in 12 patients. Responders to BPA had better exercise capacity and right heart function at baseline, but no differences in hemodynamic or respiratory function were detected between the groups. In CTEPH patients with chronic pulmonary disease (n = 14), BPA significantly improved mean pulmonary arterial pressure, pulmonary vascular resistance and right heart function parameters. Only CTEPH patients without chronic pulmonary disease (n = 48) exhibited significant improvement in 6-minute walk distance and respiratory function. Multivariate logistic regression analysis showed that pulmonary comorbidity at baseline was independently associated with the efficacy of BPA.

Conclusions

BPA provided significantly improvements in hemodynamics and right heart function in CTEPH patients, independent of pulmonary comorbidity at baseline. However, pulmonary comorbidity can negatively impact post-BPA outcomes.

Chronic Thromboembolic Pulmonary Hypertension

This JAMA Insights discusses the symptoms, diagnosis, and treatment of chronic thromboembolic pulmonary hypertension.

Diagnosis and Treatment Patterns of Chronic Thromboembolic Pulmonary Hypertension in Russia, Kazakhstan, Turkey, Lebanon, and Saudi Arabia: A Registry Study

BACKGROUND

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) in countries with limited resources have, to date, been poorly represented in registries.

OBJECTIVE

This work assesses the epidemiology, diagnosis, hemodynamic and functional parameters, and treatment of CTEPH in Russia, Kazakhstan, Turkey, Lebanon, and Saudi Arabia.

METHODS

A prospective, cohort, phase IV, observational registry with 3-year follow-up (n = 212) in patients aged ≥ 18 years diagnosed with CTEPH was created. Clinical, hemodynamic, and functional parameters were obtained at an initial visit, follow-up visits, and a final visit at the end of 3 years' observation or end of follow-up. Data were recorded on electronic case report forms. Parameters evaluated included 6-minute walking distance (6MWD), use of pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA), pulmonary hypertension (PH)-targeted therapy, and survival. All statistical analyses were exploratory and descriptive, and were performed in the overall population.

RESULTS

The most common symptoms were typical of those expected for CTEPH. Almost 90% of patients underwent right heart catheterization at diagnosis or initial study visit. In total, 66 patients (31%) underwent PEA before the initial visit; 95 patients (45%) were considered operable, 115 (54%) were inoperable, and two (1%) had no operability data. Only 26 patients (12%) had been assessed for BPA at their initial visit. PH-targeted therapy was documented at diagnosis for 77 patients (36%), most commonly a phosphodiesterase type 5 inhibitor (23%). Use of PH-targeted therapy increased to 142 patients (67%) at the initial visit, remaining similar after 3 years. Use of riociguat increased from 6% of patients at diagnosis to 38% at 3 years. Between baseline and end of observation, results for patients with paired data showed an increase in 6MWD. Survival at the end of observation was 88%.

CONCLUSIONS

These data highlight the current diagnosis and management of CTEPH in the participating countries. They show that early CTEPH diagnosis remains challenging, and use of off-label PH-targeted therapy is common.

CLINICALTRIALS

gov: NCT02637050; registered December 2015.

Performance-based outcome measures for assessing physical capacity in patients with pulmonary embolism: A scoping review

INTRODUCTION

Up to 50 % of patients surviving a pulmonary embolism (PE) report persisting shortness of breath, reduced physical capacity and psychological distress. As the PE population is heterogeneous compared to other cardiovascular patient groups, outcome measures for assessing physical capacity traditionally used in cardiac populations may not be reliable for the PE population as a whole. This scoping review aims to 1) map performance-based outcome measures (PBOMs) used for assessing physical capacity in PE research, and 2) to report the psychometric properties of the identified PBOMs in a PE population.

METHODS

The review was conducted according to the Joanna Briggs Institute framework for scoping reviews and reported according to the PRISMA-Extension for Scoping Reviews guideline.

RESULTS

The systematic search of five databases identified 4585 studies, of which 243 studies met the inclusion criteria. Of these, 185 studies focused on a subgroup of patients with chronic thromboembolic pulmonary hypertension. Ten different PBOMs were identified in the included studies. The 6-minute walk test (6MWT) and cardiopulmonary exercise test (CPET) were the most commonly used, followed by the (Modified) Bruce protocol and Incremental Shuttle Walk test. No studies reported psychometric properties of any of the identified PBOMs in a PE population.

CONCLUSIONS

Publication of studies measuring physical capacity within PE populations has increased significantly over the past 5-10 years. Still, not one study was identified, reporting the validity, reliability, or responsiveness for any of the identified PBOMs in a PE population. This should be a priority for future research in the field.

The long-term outcome of chronic thromboembolic pulmonary hypertension: Pulmonary endarterectomy and balloon pulmonary angioplasty

BACKGROUND

The long-term outcome on patients with chronic thromboembolic pulmonary hypertension (CTEPH) has not been ideal after standard medical treatment. However, good outcome for patients with CTEPH after interventions such as pulmonary endarterectomy (PEA) and balloon pulmonary angioplasty (BPA) has been reported recently. The aim of this study was to evaluate the impact of PEA or BPA on long-term outcomes for CTEPH patients in Han-Chinese population.

METHODS

This was a multicenter, prospective case-control study. Patients with CTEPH were enrolled between January, 2018 and March, 2020. They were divided into two groups, including intervention (PEA or BPA) and conservative groups. The followed-up period was 26 months after treatment. The endpoints were all-cause mortality and CTEPH mortality.

RESULTS

A total of 129 patients were enrolled and assigned to receive PEA/BPA (N = 73), or conservative therapy (N = 56). Overall, the 26-month survival rate of all-cause mortality was significantly higher in intervention group compared to that in conservative group (95.89% vs 80.36%; log-rank p = 0.0164). The similar trend was observed in the 26-month survival rate of CTEPH mortality (97.26% vs 85.71%; log-rank p = 0.0355). Regarding Cox proportional-hazard regression analysis, the hazard ratios (HRs) on patients with CTEPH receiving intervention in the outcome of all-cause mortality and CTEPH mortality were statistically significant (HR = 0.07 and p = 0.0141 in all-cause mortality; HR = 0.11 and p = 0.0461 in CTEPH mortality).

CONCLUSION

This multicenter prospective case-control study demonstrated that intervention such as PEA and BPA increased the long-term survival rate for patient with CTEPH significantly. Intervention was an independent factor in long-term outcome for patients with CTEPH, including all-cause mortality and CTEPH mortality.

[Update in the management of chronic thrombo-embolic pulmonary hypertension]

Chronic thrombo-embolic pulmonary hypertension (CTEPH) is a potentially curable form of pulmonary hypertension (PH) that develops in up to 3% of patients after pulmonary embolism (PE). In these patients, PE does not resolve, leading to organized fibrotic clots, with the development of precapillary PH as a result of the proximal obstruction of the pulmonary arteries. In addition, a distal microvasculopathy may also develop, contributing to the increase of pulmonary vascular resistance. Transthoracic echocardiography is the diagnostic tool that allows to establish the suspicion of PH. Ventilation-perfusion lung scintigraphy is the fundamental tool in the study of patients with suspected CTEPH; if it is normal, virtually rules out the diagnosis. Right heart catheterization is mandatory for the diagnosis of these patients. CTEPH is defined as the existence of symptoms, residual perfusion defects and precapillary PH after a minimum period of three months of anticoagulation. Pulmonary angiography helps determine the extent and surgical accessibility of thromboembolic lesions. CTEPH patients are candidates for long-term anticoagulation. Pulmonary endarterectomy is the treatment of choice, resulting in significant clinical and hemodynamic improvement. About 25% of patients have residual PH post-endarterectomy. Balloon pulmonary angioplasty is an endovascular technique that targets more distal lesions, being potentially useful for patients with inoperable CTEPH or persistent/recurrent PH post-endarterectomy. Both types of patients may also benefit from pharmacological treatment for PH. These three therapies are the cornerstone of CTEPH treatment, which has evolved towards a multimodal approach.

Portable Dynamic Chest Radiography: Literature Review and Potential Bedside Applications

Dynamic digital radiography (DDR) is a high-resolution radiographic imaging technique using pulsed X-ray emission to acquire a multiframe cine-loop of the target anatomical area. The first DDR technology was orthostatic chest acquisitions, but new portable equipment that can be positioned at the patient's bedside was recently released, significantly expanding its potential applications, particularly in chest examination. It provides anatomical and functional information on the motion of different anatomical structures, such as the lungs, pleura, rib cage, and trachea. Native images can be further analyzed with dedicated post-processing software to extract quantitative parameters, including diaphragm motility, automatically projected lung area and area changing rate, a colorimetric map of the signal value change related to respiration and motility, and lung perfusion. The dynamic diagnostic information along with the significant advantages of this technique in terms of portability, versatility, and cost-effectiveness represents a potential game changer for radiological diagnosis and monitoring at the patient's bedside. DDR has several applications in daily clinical practice, and in this narrative review, we will focus on chest imaging, which is the main application explored to date in the literature. However, studies are still needed to understand deeply the clinical impact of this method.

Chronic Thromboembolic Pulmonary Hypertension after Pulmonary Embolism in SARS-CoV-2

INTRODUCTION

Chronic thromboembolic pulmonary disease (CTEPD) consists of persistent pulmonary vascular obstruction on imaging and involves long-term functional limitations, with or without chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this study was to evaluate the incidence and risk factors of both persistent pulmonary vascular defects and CTEPH after hospitalization in patients with COVID-19 and PE during a 2-year follow-up.

METHODS

A prospective observational study was carried out in a tertiary hospital center. Patients were hospitalized between March 2020 and December 2021 with a diagnosis of PE during SARS-CoV-2 infection. Patients received anticoagulant treatment for at least 3 months and were followed up for 2 years. Between the third and fourth months after discharge, all patients were evaluated for the presence of residual thrombotic defects by CTPA and/or perfusion pulmonary scintigraphy. Clinical findings, lung function tests with DLCO, exercise capacity, and echocardiograms were also assessed.

RESULTS

Of the 133 patients included, 18% had persistent thrombotic defects on lung imaging at follow-up. The incidence of CTEPD was 0.75% at 2 years of follow-up. Patients with persistent defects were significantly older, had a higher prevalence of systemic arterial hypertension, higher D-dimer and NT-proBNP levels, and more severe PE at diagnosis. Furthermore, there was a higher prevalence of right ventricular dysfunction on echocardiogram at diagnosis of PE (25.0% vs. 2.7%, p = 0.006). This was the only variable independently related to persistent defects in multivariate analyses (OR: 8.13 [95% CI: 1.82-36.32], p = 0.006).

CONCLUSION

The persistence of thrombotic defects after PE is a common finding after SARS-CoV-2 infection, affecting 18% of the population. However, the incidence of CTEPH appears to be lower (0.75%) in COVID-19-related PE compared to that previously observed in PE unrelated to COVID-19.

'Fear, uncertain, tired…...' psychological distress among pulmonary hypertension patients: a qualitative interview study

BACKGROUND

Patient-centered health care for patients with pulmonary hypertension (PH) is important and requires an understanding of patient experiences. However, there is a lack of approaches to examine what's the effects and how the disease impact patients' psychological well-beings.

METHODS

We conducted qualitative interviews with PH patient representatives to understand patient psychological experiences and inform patient-centered research and care. Participants were chosen from a tertiary hospital located in northwest China. 20 patients with PH who be treated at the hospital (13 participants were women, aged 18-74 years) were strategically selected and individually interviewed. We used qualitative analysis to identify themes relating to existential psychological distress that would clarify the nature of such concerns.

RESULTS

We found that patients experience tremendous psychological distress throughout the treatment process. Four categories that describe patients' psychological experiences emerged: burden of PH treatment, fear and uncertainty about the disease, frustration in social and family role, and lack of recognition of the condition.

CONCLUSIONS

Existential concerns are salient in PH and involve the experience of loss and disruptions to the sense of self and relationships. Healthcare practitioners must work more in collaboration to detect patients' need for support and to develop the patient's own skills to manage daily life. The PH teams should tailor interventions to provide emotional, informational and instrumental support and guidance to patients.

Dynamic chest radiography for pulmonary vascular diseases: clinical applications and correlation with other imaging modalities

Dynamic chest radiography (DCR) is a novel functional radiographic imaging technique that can be used to visualize pulmonary perfusion without using contrast media. Although it has many advantages and clinical utility, most radiologists are unfamiliar with this technique because of its novelty. This review aims to (1) explain the basic principles of lung perfusion assessment using DCR, (2) discuss the advantages of DCR over other imaging modalities, and (3) review multiple specific clinical applications of DCR for pulmonary vascular diseases and compare them with other imaging modalities.

Pulmonary Embolism (PE) to Chronic Thromboembolic Pulmonary Disease (CTEPD): Findings from a Survey of UK Physicians

Chronic thromboembolic pulmonary disease (CTEPD) is a complication of pulmonary embolism (PE). We conducted an online survey of UK PE-treating physicians to understand practices in the follow-up of PE and awareness of CTEPD. The physicians surveyed (N = 175) included 50 each from cardiology, respiratory and internal medicine, plus 25 haematologists. Most (89%) participants had local guidelines for PE management, and 65% reported a PE follow-up clinic, of which 69% were joint clinics. Almost half (47%) had a protocol for the investigation of CTEPD. According to participants, 129 (74%) routinely consider a diagnosis of CTEPD and 97 (55%) routinely investigate for CTEPD, with 76% of those 97 participants investigating in patients who are symptomatic at 3 months and 22% investigating in all patients. This survey demonstrated variability in the follow-up of PE and the awareness of CTEPD and its investigation. The findings support the conduct of a national audit to understand the barriers to the timely detection of CTEPD.

Progressive Dyspnea on Exertion in an 82-Year-Old

An older patient with hereditary hemorrhagic telangiectasia and right lower lobe segmental pulmonary embolism presented with dyspnea that had worsened over 5 years; physical examination and laboratory testing showed jugular venous distension, a cardiac systolic murmur, right ventricular heave, bilateral lower extremity edema to the knees, and elevated brain-type natriuretic peptide level. What is the diagnosis and what would you do next?

Prevalence and Prognosis of Hypothyroidism in Patients With Chronic Thromboembolic Pulmonary Hypertension: An Updated Review With Description of Case Series

Hypothyroidism has been shown to have several effects on organs, including derangements in the coagulation system, impairing endothelial function, but data on the importance of hypothyroidism in the pathogenesis and development of chronic thromboembolic pulmonary hypertension (CTEPH) are limited. This report presents an updated review of the prevalence and prognosis of hypothyroidism in patients diagnosed with CTEPH, including a detailed retrospective description of the series. The descriptive case series included 34 adult patients diagnosed with CTEPH, of whom 11 patients were diagnosed with hypothyroidism. The prevalence of hypothyroidism in CTEPH was found to be 32.35%. All patients with hypothyroidism had NYHA functional Class II-III. Hemodynamic values obtained through right heart catheterization (RHC) showed that patients with hypothyroidism had significantly higher mean pulmonary arterial pressures (mPAP), with a mean of 56.91 mm Hg vs 43.93 mm Hg (p = 0.026), and the PVR in dynes/sec/cm5 was 932 vs 541 (p = 0.027). Significant differences in PVR were found in wood units (WU) 11.91 vs 7.11 (p = 0.042). The mean level of brain natriuretic peptide (BNP) between both groups was 797.3 pg/mL for patients with hypothyroidism vs 262.02 pg/mL in patients with euthyroidism (p = .032). Hypothyroidism may significantly affect patients' clinical and hemodynamic outcomes in patients with CTEPH. Hypothyroidism as a risk factor in the evaluation and treatment of these patients is vital to optimize outcomes in CTEPH; further research is warranted whether hypothyroidism therapies could alter such outcomes.

The incidence of the thrombophilic SNPs rs6025, rs1799963, rs2066865, rs2289252, and rs8176719 in chronic thromboembolic pulmonary hypertension

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) and venous thromboembolism (VTE) are thought to share many common risk factors. Our study aimed to determine the frequencies of 5 thrombosis-related gene single nucleotide polymorphisms (SNPs) associated with VTE in patients with CTEPH (n 129) compared with a control group of healthy individuals without a history of VTE (n 2637).

METHODS

The SNPs of the following genes were investigated: F5 (F V Leiden, rs6025), F2 prothrombin (rs1799963), fibrinogen gamma (FGG, rs2066865), F11 (rs2289252) and ABO (non-O, rs8176719) in both groups.

RESULTS

The study found that the rs1799963 variant was more common in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to the control group (p < .0001). The GA heterozygous variant showed a significant increase with an odds ratio (OR) of 4.480 (95% CI: 2.344-8.562) or a finding by maximum likelihood analysis (MLA) with p < .0001. Additionally, there was a notable increase in the rs8176719 variant with p < .0001 in CTEPH patients. Both the homozygous G/G variant and the heterozygous -/G variant also showed an increase, with OR of 4.2317 (95% CI: 2.45571-7.2919) and 2.4324 (95% CI: 1.46435-4.0403) respectively, or MLA (p < .0001 and p .0006). The study also revealed a higher prevalence of the heterozygous C/T variant of rs2289252 in CTEPH patients, with an OR of 1.5543 (95% CI: 1.02503-2.3568) or MLA (p .0379).

CONCLUSION

The study suggests that the observed gene polymorphisms F2 (rs1799963), ABO (rs8176719), and F11 (rs2289252) may play a role as independent heritable risk factors in the development of CTEPH.