Pulmonary endarterectomy in the management of chronic thromboembolic pulmonary hypertension

Programmed Follow-up and Quality Control of Treatment Techniques Enhance Chronic Thromboembolic Pulmonary Hypertension Management: Lessons From a Multidisciplinary Team

BACKGROUND AND OBJECTIVES

The recent developments in chronic thromboembolic pulmonary hypertension (CTEPH) are emphasizing the multidisciplinary team. We report on the changes in clinical practice following the development of a multidisciplinary team, based on our 7 years of experience.

METHODS

Multidisciplinary team was established in 2015 offering both balloon pulmonary angioplasty (BPA) and pulmonary endarterectomy (PEA) with technical upgrades by internal and external expertise. For operable cases, PEA was recommended as the primary treatment modality, followed by pulmonary angiography and right heart catheterization after 6 months to evaluate treatment effect and identify patients requiring further BPA. For patients with inoperable anatomy or high surgical risk, BPA was recommended as the initial treatment modality. Patient data and clinical outcomes were closely monitored.

RESULTS

The number of CTEPH treatments rapidly increased and postoperative survival improved after team development. Before the team, 38 patients were treated by PEA for 18 years; however, 125 patients were treated by PEA or BPA after the team for 7 years. The number of PEA performed was 64 and that of BPA 342 sessions. World Health Organization functional class I or II was achieved in 93% of patients. The patients treated with PEA was younger, male dominant, higher pulmonary artery pressure, and smaller cardiac index, than BPA-only patients. In-hospital death after PEA was only 1 case and none after BPA.

CONCLUSIONS

The balanced development of BPA and PEA through a multidisciplinary team approach proved synergistic in increasing the number of actively treated CTEPH patients and improving clinical outcomes.

The management pattern and outcomes of chronic thromboembolic pulmonary hypertension: rationale and design for a Chinese real-world study

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive pulmonary vascular disorder with substantial morbidity and mortality, also a disease underdiagnosed and undertreated. It is potentially curable by pulmonary endarterectomy (PEA) in patients with surgically accessible thrombi. Balloon pulmonary angioplasty (BPA) and targeted medical therapy are options for patients with distal lesions or persistent/recurrent pulmonary hypertension after PEA. There is an urgent need to increase the awareness of CTEPH. Qualified CTEPH centers are still quite limited. Baseline characteristics, management pattern and clinical outcome of CTEPH in China needs to be reported.

METHODS AND DESIGN

The CHinese reAl-world study to iNvestigate the manaGEment pattern and outcomes of chronic thromboembolic pulmonary hypertension (CHANGE) study is designed to provide the multimodality treatment pattern and clinical outcomes of CTEPH in China. Consecutive patients who are ≥ 14 year-old and diagnosed with CTEPH are enrolled. The diagnosis of CTEPH is confirmed in right heart catheterization and imaging examinations. The multimodality therapeutic strategy, which consists of PEA, BPA and targeted medical therapy, is made by a multidisciplinary team. The blood sample and tissue from PEA are stored in the central biobank for further research. The patients receive regular follow-up every 3 or 6 months for at least 3 years. The primary outcomes include all-cause mortality and changes in functional and hemodynamic parameters from baseline. The secondary outcomes include the proportion of patients experiencing lung transplantation, the proportion of patients experiencing heart and lung transplantation, and changes in health-related quality of life. Up to 31 December 2023, the study has enrolled 1500 eligible patients from 18 expert centers.

CONCLUSIONS

As a real-world study, the CHANGE study is expected to increase our understanding of CTEPH, and to fill the gap between guidelines and the clinical practice in the diagnosis, assessment and treatment of patients with CTEPH. REGISTRATION NUMBER IN CLINICALTRIALS.GOV: NCT05311072.

Pulmonary Hypertension in Connective Tissue Diseases Other than Systemic Sclerosis

Pulmonary hypertension (PH) is a known complication of certain connective tissue diseases (CTDs), with systemic sclerosis (SSc) being the most common in the Western world. However, PH in association with non-SSc CTD such as systemic lupus erythematous, mixed connective tissue disease, and primary Sjögren's syndrome constitutes a distinct subset of patients with inherently different epidemiologic profiles, pathophysiologic mechanisms, clinical features, therapeutic options, and prognostic implications. The purpose of this review is to inform a practical approach for clinicians evaluating patients with non-SSc CTD-associated PH.The development of PH in these patients involves a complex interplay between genetic factors, immune-mediated mechanisms, and endothelial cell dysfunction. Furthermore, the broad spectrum of CTD manifestations can contribute to the development of PH through various pathophysiologic mechanisms, including intrinsic pulmonary arteriolar vasculopathy (pulmonary arterial hypertension, Group 1 PH), left-heart disease (Group 2), chronic lung disease (Group 3), chronic pulmonary artery obstruction (Group 4), and unclear and/or multifactorial mechanisms (Group 5). The importance of diagnosing PH early in symptomatic patients with non-SSc CTD is highlighted, with a review of the relevant biomarkers, imaging, and diagnostic procedures required to establish a diagnosis.Therapeutic strategies for non-SSc PH associated with CTD are explored with an in-depth review of the medical, interventional, and surgical options available to these patients, emphasizing the CTD-specific considerations that guide treatment and aid in prognosis. By identifying gaps in the current literature, we offer insights into future research priorities that may prove valuable for patients with PH associated with non-SSc CTD.

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.

Development and web deployment of prediction model for pulmonary arterial pressure in chronic thromboembolic pulmonary hypertension using machine learning

BACKGROUND AND PURPOSE

Mean pulmonary artery pressure (mPAP) is a key index for chronic thromboembolic pulmonary hypertension (CTEPH). Using machine learning, we attempted to construct an accurate prediction model for mPAP in patients with CTEPH.

METHODS

A total of 136 patients diagnosed with CTEPH were included, for whom mPAP was measured. The following patient data were used as explanatory variables in the model: basic patient information (age and sex), blood tests (brain natriuretic peptide (BNP)), echocardiography (tricuspid valve pressure gradient (TRPG)), and chest radiography (cardiothoracic ratio (CTR), right second arc ratio, and presence of avascular area). Seven machine learning methods including linear regression were used for the multivariable prediction models. Additionally, prediction models were constructed using the AutoML software. Among the 136 patients, 2/3 and 1/3 were used as training and validation sets, respectively. The average of R squared was obtained from 10 different data splittings of the training and validation sets.

RESULTS

The optimal machine learning model was linear regression (averaged R squared, 0.360). The optimal combination of explanatory variables with linear regression was age, BNP level, TRPG level, and CTR (averaged R squared, 0.388). The R squared of the optimal multivariable linear regression model was higher than that of the univariable linear regression model with only TRPG.

CONCLUSION

We constructed a more accurate prediction model for mPAP in patients with CTEPH than a model of TRPG only. The prediction performance of our model was improved by selecting the optimal machine learning method and combination of explanatory variables.

Long-term effects of pulmonary endarterectomy on pulmonary hemodynamics, cardiac function, and exercise capacity in chronic thromboembolic pulmonary hypertension

BACKGROUND

Long-term changes in exercise capacity and cardiopulmonary hemodynamics after pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have been poorly described.

METHODS

We analyzed the data from 2 prospective surgical CTEPH cohorts in Hammersmith Hospital, London, and Amsterdam UMC. A structured multimodal follow-up was adopted, consisting of right heart catheterization, cardiac magnetic resonance imaging, and cardiopulmonary exercise testing before and after PEA. Preoperative predictors of residual pulmonary hypertension (PH; mean pulmonary artery pressure >20 mm Hg and pulmonary vascular resistance ≥2 WU) and long-term exercise intolerance (VO2max <80%) at 18 months were analyzed.

RESULTS

A total of 118 patients (61 from London and 57 from Amsterdam) were included in the analysis. Both cohorts displayed a significant improvement of pulmonary hemodynamics, right ventricular (RV) function, and exercise capacity 6 months after PEA. Between 6 and 18 months after PEA, there were no further improvements in hemodynamics and RV function, but the proportion of patients with impaired exercise capacity was high and slightly increased over time (52%-59% from 6 to 18 months). Long-term exercise intolerance was common and associated with preoperative diffusion capacity for carbon monoxide (DLCO), preoperative mixed venous oxygen saturation, and postoperative PH and right ventricular ejection fraction (RVEF). Clinically significant RV deterioration (RVEF decline >3%; 5 [9%] of 57 patients) and recurrent PH (5 [14%] of 36 patients) rarely occurred beyond 6 months after PEA. Age and preoperative DLCO were predictors of residual PH post-PEA.

CONCLUSIONS

Restoration in exercise tolerance, cardiopulmonary hemodynamics, and RV function occurs within 6 months. No substantial changes occurred between 6 and 18 months after PEA in the Amsterdam cohort. Nevertheless, long-term exercise intolerance is common and associated with postoperative RV function.

Insufficiency of quality of life as the treatment endpoint for balloon pulmonary angioplasty in inoperable chronic thromboembolic pulmonary hypertension

Background and Objectives

The ability of a quality of life (QoL) to guide balloon pulmonary angioplasty (BPA) among patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) has not been fully investigated. This study explored the relationship between QoL scores and hemodynamics in CTEPH patients after BPA and examined whether QoL could be applied as a treatment endpoint.

Materials and Methods

This cohort study included patients with inoperable CTEPH who had undergone at least four sessions of BPA. The patients' demographic and clinical data as well as hemodynamic parameters and scores from the RAND 36-item short-form QoL questionnaire were recorded and compared before and after BPA.

Results

After BPA treatments, clinical characteristics, hemodynamic parameters, as well as QoL score improved significantly. A physical component summary (PCS) score of 35 or 46 can be used as the cutoff value for predicting better World Health Organization functional classification (WHO FC). Patients who had a higher PCS would have longer 6-min walk distance (6MWD), lower pulmonary vascular resistance (PVR), and better cardiac output (CO) both before and after BPA. However, 19 patients (55.9%) with a higher PCS score after BPA did not achieve the goal of mean pulmonary arterial pressure (mPAP) ≤30 mmHg. During the follow-up period, a significant reduction of PVR was observed, but the PCS score improved a little.

Conclusions

QoL is a useful tool for assessing the exercise endurance of patients with inoperable CTEPH treated with BPA, but is insufficient to serve as a treatment endpoint for BPA.

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.

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.

Post-Pulmonary Embolism Syndrome: An Update Based on the Revised AWMF-S2k Guideline

In survivors of acute pulmonary embolism (PE), the post-PE syndrome (PPES) may occur. In PPES, patients typically present with persisting or progressive dyspnea on exertion despite 3 months of therapeutic anticoagulation. Therefore, a structured follow-up is warranted to identify patients with chronic thromboembolic pulmonary disease (CTEPD) with normal pulmonary pressure or chronic thromboembolic pulmonary hypertension (CTEPH). Both are currently understood as a dual vasculopathy, that is, secondary arterio- and arteriolopathy, affecting the large and medium-sized pulmonary arteries as well as the peripheral vessels (diameter < 50 µm). The follow-up algorithm after acute PE commences with identification of clinical symptoms and risk factors for CTEPH. If indicated, a stepwise performance of echocardiography, ventilation-perfusion scan (or alternative imaging), N-terminal prohormone of brain natriuretic peptide (NT-proBNP) level, cardiopulmonary exercise testing, and pulmonary artery catheterization with angiography should follow. CTEPH patients should be treated in a multidisciplinary center with adequate experience in the complex therapeutic options, comprising pulmonary endarterectomy, balloon pulmonary angioplasty, and pharmacological interventions.

The Initial Experience of Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension in Latvia

Background: Treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) or persistent pulmonary hypertension after pulmonary endarterectomy (PEA) include targeted medical therapy and balloon pulmonary angioplasty (BPA). BPA is an emerging treatment modality that has been reported to improve functional capacity, pulmonary hemodynamics, and right ventricular function. Reports from expert centers are promising, but more data are needed to make the results more generalizable. Materials and Methods: We conducted a prospective analysis of nine consecutive CTEPH patients who underwent balloon pulmonary angioplasty (BPA) sessions at Pauls Stradins Clinical University Hospital in Riga, Latvia between 1 April 2022 and 1 July 2023. We assessed World Health Organization (WHO) functional class, 6 min walk distance (6MWD), blood oxygen saturation (SpO2), brain natriuretic peptide (BNP) level at baseline and 3 months after the first BPA session. For two patients on whom repeated BPA sessions were performed, we additionally assessed cardiac output (CO), pulmonary vascular resistance (PVR), and mean pulmonary artery pressure (mPAP). Results: A total of 12 BPA procedures for nine patients were performed; repeated BPA sessions were performed for two patients. Our results show a reduction in BNP levels and improvement in WHO functional class, 6MWD, and SpO2 after the first BPA session. Improvement in 6MWD was statistically significant. Additionally, an improvement in pulmonary hemodynamic parameters was observed. Conclusions: Our data show that BPA is an effective interventional treatment modality, improving both the pulmonary hemodynamics and functional status. Moreover, BPA is safe and excellently tolerated.

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.

Role of Surgical and Medical Management of Chronic Thromboembolic Pulmonary Hypertension: A Systematic Review

Chronic thromboembolic pulmonary hypertension (CTEPH) is underdiagnosed and has recently surfaced as one of the leading triggers of severe pulmonary hypertension. This disease process is described by structural changes of pulmonary arteries such as fibrous stenosis, complete obliteration, or the presence of a resistant intraluminal thrombus, resulting in increased pulmonary resistance and eventually progressing to right-sided heart failure. Hence, this study aims to describe the current treatments for CTEPH and their efficacy in hemodynamic improvement and prevention of recurring thromboembolic episodes in patients. This systematic review promptly follows the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. On February 13, 2022, our team searched through the following databases: PubMed, ProQuest, and ScienceDirect. The following keywords were used across all databases: CTEPH AND Pulmonary Endarterectomy (PEA), CTEPH AND Balloon Pulmonary Angioplasty (BPA), and CTEPH AND Medical Therapy OR Anticoagulation therapy. Twenty-nine thousand eighty-nine articles on current management techniques (PEA, Balloon angioplasty, anticoagulants) were selected, analyzed, and reviewed with each other. We found 19 articles concerning PEA, 15 concerning BPA, and six regarding anticoagulants. Most papers showed high success rates and promising evidence of PEA and anticoagulants as a post-operative regimen. BPA was the least preferred but is still reputable in patients unfit for invasive techniques. CTEPH is a condition presenting with either fibrous stenosis, complete obliteration of the artery, or a clogged thrombus. Recent studies have shown three techniques that physicians have used to treat CTEPH: balloon-pulmonary angioplasty, PEA, and medical management with anticoagulants. PEA followed by anticoagulants is preferred to balloon pulmonary angioplasties. CTEPH is an ongoing topic in research; as it continues to be researched, we hope to see more management techniques available.

Pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension with bronchial obstruction by a carcinoid tumor

Pulmonary endarterectomy (PEA) is a standard treatment for chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH combined with bronchial obstruction by a tumor is rare but should be assessed carefully because PEA for obstructed segments can be less therapeutic and make the subsequent surgical resection challenging. This report describes a case of CTEPH with bronchial obstruction by a typical carcinoid tumor in a 75-year-old man. On-site evaluation and removal of the obstructive tumor were performed bronchoscopically, increasing the effectiveness of subsequent PEA for all affected pulmonary segments. This report illustrates a PEA strategy to treat CTEPH with bronchial tumor obstruction.

Perioperative Management in Pulmonary Endarterectomy

Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (PH), provided lesions are proximal enough in the pulmonary vasculature to be surgically accessible and the patient is well enough to benefit from the operation in the longer term. It is a major cardiothoracic operation, requiring specialized techniques and instruments developed over several decades to access and dissect out the intra-arterial fibrotic material. While in-hospital operative mortality is low (<5%), particularly in high-volume centers, careful perioperative management in the operating theater and intensive care is mandatory to balance ventricular performance, fluid balance, ventilation, and coagulation to avoid or treat complications. Reperfusion pulmonary edema, airway hemorrhage, and right ventricular failure are the most problematic complications, often requiring the use of extracorporeal membrane oxygenation to bridge to recovery. Successful PEA has been shown to improve both morbidity and mortality in large registries, with survival >70% at 10 years. For patients not suitable for PEA or with residual PH after PEA, balloon pulmonary angioplasty and/or PH medical therapy may prove beneficial. Here, we describe the indications for PEA, specific surgical and perioperative strategies, postoperative monitoring and management, and approaches for managing residual PH in the long term.

Hyperlactatemia in patients undergoing pulmonary endarterectomy with deep hypothermic circulatory arrest: Risk factors and its effects on the outcome

INTRODUCTION

To determine the risk factors of hyperlactatemia in pulmonary endarterectomy (PEA) surgery and assess whether elevated blood lactate levels are associated with adverse outcomes.

METHODS

In this retrospective observational study, a total of 111 consecutive patients who underwent PEA for chronic thromboembolic pulmonary hypertension at the XXX Hospital between December 2016 and January 2022 were included. We retrospectively evaluated arterial blood samples analyzed intraoperatively. The pre- and intraoperative risk factors for hyperlactatemia and the postoperative outcomes were recorded.

RESULTS

Lactate levels gradually increased during surgery. The optimal cut-off lactate level for major postoperative complications, calculated using receiver operating characteristic analysis, was 7.0 mmol/L. Deep hypothermic circulatory arrest (DHCA) duration, nadir hematocrit, and preoperative pulmonary vascular resistance were risk factors for lactate levels >7 mmol/L. Moreover, the intraoperative peak lactate level during PEA under DHCA was found to be a statistically significant predictor of major complications being associated with longer mechanical ventilation time (r = 0.294; p = .003) and intensive care unit length of stay (r = 0.327; p = .001).

CONCLUSIONS

Deep hypothermic circulatory arrest duration, nadir hematocrit, and preoperative pulmonary vascular resistance were associated with hyperlactatemia. Increased lactate levels were independent predictors of longer mechanical ventilation time, intensive care unit length of stay, and major complications.

Changes in the management of chronic thromboembolic pulmonary hypertension over a 10-year period, in a French expert regional competence centre

Over the last few years, the advent of balloon pulmonary angioplasty (BPA) had led to changes in the management of chronic thromboembolic pulmonary hypertension (CTEPH). We reviewed data from 98 CTEPH patients diagnosed during the last decade in a pulmonary hypertension (PH) expert centre. The management modalities of 2 periods (Period A: 2011-15 and Period B: 2016-20) were compared. Age (period A: 72 [58-80] years; period B: 69 [62-79] years), clinical (New York Heart Association (NYHA) functional class III-IV: 25/41, 61% vs 39/57, 68%), and hemodynamic assessments (pulmonary vascular resistance: 7.5 [6.2-8.7] WU vs 8.0 [6.0-10.2] WU) at baseline were not significantly different. Pulmonary endarterectomy was performed in less than one third of patients (12, 29.3% vs 15, 26.3%). For patients not eligible for surgery, medical therapy was mostly prescribed alone during period A (medical therapy alone, patients diagnosed in period A: 61% vs in period B: 17.5%) while it was associated with BPA during period B (medical therapy + BPA, 12% vs 61.4%). The 5-year survival rate was excellent for patients who underwent surgery (96.3%) or BPA (95.2%), but was only 42.1% for patients under oral medication only (p < 0.0001). Patients diagnosed with CTEPH who cannot be operated should undergo BPA. The survival rate after BPA is as good as after surgery and significantly better than that of oral medication only.

Safety and efficacy of direct oral anticoagulants in patients with chronic thromboembolic pulmonary hypertension

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) remains an underdiagnosed disease. Anticoagulation is essential in its therapy to prevent recurrent venous thromboembolism (VTE). According to some international guidelines, vitamin K antagonists (VKA) remain the gold standard. Nevertheless, direct oral anticoagulants (DOAC) are widely used, partly because of numerous advantages. The objective of this study was to determine if DOAC is an effective and safe alternative to VKA in CTEPH patients.

MATERIALS AND METHODS

A retrospective observational study was conducted between 2001 and 2021 in a CTEPH Clinic of a tertiary care hospital. We recorded demographic characteristics, anticoagulant therapies and pulmonary hypertension treatments received. Safety outcomes were bleeding events and deaths while efficacy outcomes were recurrent VTE events.

RESULTS

Among the study population (N = 205), the distribution of anticoagulant used transitioned from majority on VKA to majority on DOAC. In 2020, 23 (19 %) were on VKA and 97 (78 %) on DOAC. Among 11 VTE events occurring during follow-up, 7 were in the VKA group (1.10 %/person-year) and 1 in the DOAC group (0.32 %/person-year). Rates of VTE recurrence were not significantly different in those treated with DOAC compared to VKA (P = 0.21). Total bleeding rate on VKA (2.52 %/person-year) and DOAC (2.52 %/person-year) were the same (P = 1.00). Among 27 patients who died, no deaths occurred as a consequence of bleeding or VTE events.

CONCLUSION

Bleeding and VTE events were not higher in CTEPH patients receiving DOAC compared to VKA which adds confidence to considering DOAC as an effective and safe alternative for long term anticoagulation in CTEPH patients.

Chronic thromboembolic pulmonary hypertension and the post-pulmonary embolism (PE) syndrome

Over a third of patients surviving acute pulmonary embolism (PE) will experience long-term cardiopulmonary limitations. Persistent thrombi, impaired gas exchange, and altered hemodynamics account for aspects of the postpulmonary embolism syndrome that spans mild functional limitations to debilitating chronic thromboembolic pulmonary hypertension (CTEPH), the most worrisome long-term consequence. Though pulmonary endarterectomy is potentially curative for the latter, less is understood surrounding chronic thromboembolic disease (CTED) and post-PE dyspnea. Advances in pulmonary vasodilator therapies and growing expertise in balloon pulmonary angioplasty provide options for a large group of patients ineligible for surgery, or those with persistent postoperative pulmonary hypertension. In this clinical review, we discuss epidemiology and pathophysiology as well as advances in diagnostics and therapeutics surrounding the spectrum of disease that may follow months after acute PE.

Distal vessel pulmonary thromboendarterectomy: Results from a single institution

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is primarily managed by pulmonary thromboendarterectomy (PTE). As advanced surgical techniques permit resection at the segmental and subsegmental level, PTE can now be curative for CTEPH mostly involving the distal pulmonary arteries.

METHODS

Between January 2017 and June 2021, consecutive patients undergoing PTE were categorized according to the most proximal level of chronic thrombus resection: Level I (main pulmonary artery), Level II (lobar), Level III (segmental) and Level IV (subsegmental). Proximal disease patients (any Level I or II) were compared to distal disease (Level III or IV bilaterally) patients. Demographics, medical history, preoperative pulmonary hemodynamics, and immediate postoperative outcomes were obtained for each group.

RESULTS

During the study period, 794 patients underwent PTE, 563 with proximal disease and 231 with distal disease. Patients with distal disease more frequently had a history of an indwelling intravenous device, splenectomy, upper extremity thrombosis or use thyroid replacement and less often had prior lower extremity thrombosis or hypercoagulable state. Despite more use of PAH-targeted medications in the distal disease group (63.2% vs 50.1%, p < 0.001), preoperative hemodynamics were similar. Both patient groups exhibited significant improvements in pulmonary hemodynamics postoperatively with comparable in-hospital mortality rates. Compared to proximal disease, a lower percentage of patients with distal disease showed residual pulmonary hypertension (3.1% vs 6.9%, p = 0.039) and airway hemorrhage (3.0% vs 6.6%, p = 0.047) postoperatively.

CONCLUSIONS

Thromboendarterectomy for distal (segmental and subsegmental) CTEPH is technically feasible and may result in favorable pulmonary hemodynamic outcomes, without increased mortality or morbidity.

Predicting Patient Status in Chronic Thromboembolic Pulmonary Hypertension Using a Biophysical Model

Chronic thromboembolic pulmonary hypertension (CTEPH) involves abnormally high blood pressure in the pulmonary vessels and is associated with small vessel vasculopathy and pre-capillary proximal occlusions. Management of CTEPH disease is challenging, therefore accurate diagnosis is crucial in ensuring effective treatment and improved patient outcomes. The treatment of choice for CTEPH is pulmonary endarterectomy, which is an invasive surgical intervention to remove thrombi. Following PEA, a number of patients experience poor outcomes or worse-than-expected improvements, which may indicate that they have significant small vessel disease. A method that can predict the extent of distal remodelling may provide useful clinical information to plan appropriate CTEPH patient treatment. Here, a novel biophysical modelling approach has been developed to estimate and quantify the extent of distal remodelling. This method includes a combination of mathematical modelling and computed tomography pulmonary angiography to first model the geometry of the pulmonary arteries and to identify the under-perfused regions in CTEPH. The geometric model is then used alongside haemodynamic measurements from right heart catheterisation to predict distal remodelling. In this study, the method is tested and validated using synthetically generated remodelling data. Then, a preliminary application of this technique to patient data is shown to demonstrate the potential of the approach for use in the clinical setting.Clinical relevance- Patient-specific modelling can help provide useful information regarding the extent of distal vasculopathy on a per-patient basis, which remains challenging. Physicians can be unsure of outcomes following pulmonary endarterectomy. Therefore, the predictive aspect of the patient's response to surgery can help with clinical decision-making.

Balloon pulmonary angioplasty outcomes in patients previously treated by pulmonary endarterectomy surgery are inferior to those of inoperable patients

Pulmonary endarterectomy (PEA) may not achieve full clearance of vascular obstructions in patients with more distal chronic thromboembolic pulmonary hypertension (CTEPH). Balloon pulmonary angioplasty (BPA) may be indicated to treat these residual vascular lesions. We compared whether patients post-PEA (PP) treated by BPA derived similar benefit to those who had inoperable CTEPH (IC), and assessed predictors of BPA response after surgery. We treated 109 patients with BPA-89 with IC and 20 PP. Serial right heart catheterization performed at baseline (immediately before BPA) and 3 months after completing BPA, compared pulmonary vascular resistance (PVR), mean pulmonary artery pressure (mPAP) as well as change in WHO functional class and 6-minute walk distance. We also assessed the impact of total thrombus tail length (TTTL) from photographed PEA surgical specimens and PP computed tomography pulmonary angiography (CTPA)-quantified residual disease burden on BPA response. PP and IC groups did not differ significantly in terms of demographics, baseline hemodynamics or procedural characteristics. However, IC derived greater hemodynamic benefit from BPA: ΔPVR (-27.9 ± 20.2% vs. -13.9 ± 23.9%, p < 0.05) and ΔmPAP (-17.1 ± 14.4% vs. -8.5 ± 18.0%, p < 0.05). There was a negative correlation between pre-BPA PVR and TTTL (r = -0.47, p < 0.05) which persisted post-BPA. PVR, mPAP, WHO FC and 6MWD were not improved significantly post-BPA in PP patients. BPA response was not related to TTTL terciles or CTPA-quantified residual disease burden. Patients PP experienced inferior response to BPA, despite similar baseline and procedural characteristics to IC. BPA does not abolish the relationship between TTTL and postsurgical PVR in PP patients, suggesting that BPA is less effective in treating residual PH after surgery in an experienced surgical center.

Pulmonary artery blood flow dynamics in chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension is caused by incomplete resolution and organization of thrombi. Blood flow dynamics are involved in thrombus formation; however, only a few studies have reported on pulmonary artery blood flow dynamics in patients with chronic thromboembolic pulmonary hypertension. Furthermore, the effects of treatment interventions on pulmonary artery blood flow dynamics are not fully understood. The aim of the study was to evaluate pulmonary artery blood flow dynamics in patients with chronic thromboembolic pulmonary hypertension before and after pulmonary endarterectomy and balloon pulmonary angioplasty, using computational fluid dynamics. We analyzed patient-specific pulmonary artery models of 10 patients with chronic thromboembolic pulmonary hypertension and three controls using computational fluid dynamics. In patients with chronic thromboembolic pulmonary hypertension, flow velocity and wall shear stress in the pulmonary arteries were significantly decreased, and the oscillatory shear index and blood stagnation volume were significantly increased than in controls. Pulmonary endarterectomy induced redistribution of pulmonary blood flow and improved blood flow dynamics in the pulmonary artery. Balloon pulmonary angioplasty improved pulmonary blood flow disturbance, decreased blood flow stagnation, and increased wall shear stress, leading to vasodilatation of the distal portion of the pulmonary artery following balloon pulmonary angioplasty treatment.

Pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension: Relationship between treated branches and outcome

BACKGROUND

In patients with chronic thromboembolic pulmonary hypertension (CTEPH) undergoing pulmonary endarterectomy (PEA) it is important to minimize residual obstructions, in order to achieve low postoperative pulmonary vascular resistances and better clinical results. The aim of the study was to test the hypothesis that the greater the number of pulmonary artery branches treated at surgery, the better the hemodynamic and clinical outcome after PEA.

METHODS

In 564 consecutive CTEPH patients undergoing PEA the count of the number of treated branches was performed directly on the surgical specimens. Post-operative follow-up visits were scheduled at 3 months and 12 months after surgery including right heart catheterization and modified Bruce test.

RESULTS

The population was divided into tertiles based on the number of treated branches: Group 1 (from 4 to 30 treated branches, n = 194 patients); Group 2 (from 31 to 43 treated branches, n = 190 patients); Group 3 (from 44 to 100 treated branches, n = 180 patients). At 3 and at 12 months after PEA, after adjustment for confounders, patients in the highest tertile of treated branches had significantly lower values of pulmonary vascular resistance and higher values of pulmonary arterial compliance as compared to the other two groups (p < 0.002). Hospital mortality was 3% in Group 3, 6% in Group 2 and 10% in Group 1 (overall p = 0.035).

CONCLUSIONS

In CTEPH patients undergoing PEA, a higher number of treated pulmonary artery branches is associated with a better hemodynamic and a better clinical outcome at 3 months and 12 months after surgery.

Treatment Response Evaluation by Computed Tomography Pulmonary Vasculature Analysis in Patients With Chronic Thromboembolic Pulmonary Hypertension

OBJECTIVE

To quantitatively assess the pulmonary vasculature using non-contrast computed tomography (CT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) pre- and post-treatment and correlate CT-based parameters with right heart catheterization (RHC) hemodynamic and clinical parameters.

MATERIALS AND METHODS

A total of 30 patients with CTEPH (mean age, 57.9 years; 53% female) who received multimodal treatment, including riociguat for ≥ 16 weeks with or without balloon pulmonary angioplasty and underwent both non-contrast CT for pulmonary vasculature analysis and RHC pre- and post-treatment were included. The radiographic analysis included subpleural perfusion parameters, including blood volume in small vessels with a cross-sectional area ≤ 5 mm² (BV5) and total blood vessel volume (TBV) in the lungs. The RHC parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), and cardiac index (CI). Clinical parameters included the World Health Organization (WHO) functional class and 6-minute walking distance (6MWD).

RESULTS

The number, area, and density of the subpleural small vessels increased after treatment by 35.7% (P < 0.001), 13.3% (P = 0.028), and 39.3% (P < 0.001), respectively. The blood volume shifted from larger to smaller vessels, as indicated by an 11.3% increase in the BV5/TBV ratio (P = 0.042). The BV5/TBV ratio was negatively correlated with PVR (r = -0.26; P = 0.035) and positively correlated with CI (r = 0.33; P = 0.009). The percent change across treatment in the BV5/TBV ratio correlated with the percent change in mPAP (r = -0.56; P = 0.001), PVR (r = -0.64; P < 0.001), and CI (r = 0.28; P = 0.049). Furthermore, the BV5/TBV ratio was inversely associated with the WHO functional classes I-IV (P = 0.004) and positively associated with 6MWD (P = 0.013).

CONCLUSION

Non-contrast CT measures could quantitatively assess changes in the pulmonary vasculature in response to treatment and were correlated with hemodynamic and clinical parameters.

A modified perfusion protocol for pulmonary endarterectomy in a patient with a hematologic malignancy treated with a tyrosine kinase inhibitor

Tyrosine kinase inhibitors (TKI) are known to be highly effective in the treatment of various cancers with kinase-domain mutations such as chronic myelogenous leukemia. However, they have important side effects such as increased vascular permeability and pulmonary hypertension. In patients undergoing pulmonary endarterectomy with deep hypothermic circulatory arrest, these side effects may exacerbate postoperative complications such as reperfusion edema and persistent pulmonary hypertension. We report on a simple modification of the perfusion strategy to increase intravascular oncotic pressure by retrograde autologous priming and the addition of packed cells and albumin in a patient treated with a TKI.

Effects of balloon pulmonary angioplasty procedure on electrocardiographic parameters in patients with chronic thromboembolic pulmonary hypertension

AIM

The aim of the present study was to evaluate the value of electrocardiography (ECG) in predicting postoperative hemodynamic improvement in patients with chronic thromboembolic pulmonary hypertension (CTEPH) undergoing balloon pulmonary angioplasty (BPA).

MATERIAL AND METHODS

A total of 32 patients were included in the study. During ECG analysis, parameters that have been suggested to be related to right ventricular hypertrophy and/or dilatation were evaluated. The significance of the change in each parameter obtained at the pre-BPA visit and at the scheduled control visit 6 months after BPA was tested. In addition to ECG analysis, data related to right heart catheterization (RHC) and echocardiography, B-type natriuretic peptide (BNP) levels and World Health Organization (WHO) functional classifications of all patients were also recorded. The relationship between the amount of possible change in ECG parameters and the amount of possible change in hemodynamic parameters was investigated.

RESULTS

The Daniel score, which has been suggested to have prognostic value in acute pulmonary embolism, decreased from 8.22 ± 5.68 to 6.56 ± 5.55 after the BPA procedure (p: 0.035). Among all parameters studied, only T wave height (V₂ t) in V₂ derivation changed significantly from -0.77 ± 2.39 to 1.27 ± 2.58 mm (p: 0.036). The amount of change in V₂ T was found to significantly correlate with the amount of change in systolic right ventricular pressure, mean pulmonary artery pressure, pulmonary vascular resistance, and systemic vascular resistance.

CONCLUSION

Postprocedural T wave changes in lead V2 might serve as a marker of hemodynamic improvement in patients with CTEPH who undergo BPA.

Utility of cardiac magnetic resonance feature tracking strain assessment in chronic thromboembolic pulmonary hypertension for prediction of REVEAL 2.0 high risk status

Chronic thromboembolic pulmonary hypertension may be cured by pulmonary endarterectomy (PEA). Thromboembolic disease distribution/PEA success primarily determines prognosis but risk scoring criteria may be adjunctive. Right ventriculoarterial (RV-PA) and ventriculoatrial (RV-right atrium [RA]) coupling may be evaluated by cardiac MRI (CMR) feature tracking deformation/strain assessment. We characterized biatrial and biventricular CMR feature tracking (FT) strain parameters following PEA and tested the ability of CMR FT to identify REVEAL 2.0 high-risk status. We undertook a retrospective single-center cross-sectional study of patients (n = 57) who underwent PEA (2015-2020). All underwent pre and postoperative catheterization and CMR. Pulmonary arterial hypertension validated risk scores were calculated. Significant postoperative improvements were observed in mean pulmonary artery pressure (mPAP) (pre-op 45 ± 11 mmHg vs. post-op 26 ± 11 mmHg; p < 0.001) and PVR however a large proportion had residual pulmonary hypertension (45%; mPAP ≥25 mmHg). PEA augmented left heart filling with left ventricular end diastolic volume index and left atrial volume index increment. Left ventricular ejection fraction was unchanged postoperatively but LV global longitudinal strain improved (pre-op median -14.2% vs. post-op -16.0%; p < 0.001). Right ventricular (RV) geometry and function also improved with reduction in RV mass. Most had uncoupled RV-PA relationships which recovered (pre-op right ventricular free wall longitudinal strain -13.2 ± 4.8%, RV stroke volume/right ventricular end systolic volume ratio 0.78 ± 0.53 vs. post-op -16.8 ± 4.2%, 1.32 ± 0.55; both p < 0.001). Postoperatively, there were six REVEAL 2.0 high-risk patients, best predicted by impaired RA strain which was superior to traditional volumetric parameters (area under the curve [AUC] 0.99 vs. RVEF AUC 0.88). CMR deformation/strain evaluation can offer insights into coupling recovery; RA strain may be an expeditious surrogate for the more laborious REVEAL 2.0 score.

Comparison of the safety and efficacy of balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension patients with surgically accessible and inaccessible lesions

BACKGROUND

Although pulmonary endarterectomy is the treatment of choice for chronic thromboembolic pulmonary hypertension, not all patients are eligible. While balloon pulmonary angioplasty is an alternative for such patients, its efficacy and safety may differ between patients with and without surgically accessible lesions.

METHODS

This study involved 344 patients treated with balloon pulmonary angioplasty who were ineligible for pulmonary endarterectomy. Based on the angiographical lesion location, patients were divided into the surgically accessible (Group 1) and inaccessible (Group 2) groups, and percent changes in hemodynamics and clinical parameters before and after balloon pulmonary angioplasty were investigated. We also conducted survival analyses using Kaplan-Meier analysis.

RESULTS

While no differences in baseline characteristics were identified between the groups, balloon pulmonary angioplasty significantly improved hemodynamics in both groups, without any difference regarding the incidence of complications. Meanwhile, the percent changes in the mean pulmonary arterial pressure, pulmonary vascular resistance, 6-min walk distance, right ventricular area index on echocardiography, and the achievement rate of World Health Organization functional class I after balloon pulmonary angioplasty were significantly lower in Group 1 than in Group 2. The cumulative survival rates at 1, 5, and 10 years after balloon pulmonary angioplasty were not significantly different between the two groups (Group 1: 92.5%, 86.1%, 84.3%; and Group 2: 96.5%, 92.9%, 90.1%, respectively).

CONCLUSIONS

The outcome of balloon pulmonary angioplasty in inoperable patients with surgically accessible proximal lesions was acceptable; however, further investigations are necessary to clarify the optimal treatment for such patients.

[Pulmonary Endarterectomy and Treatment for Chronic Thromboembolic Pulmonary Hypertension]

Pulmonary Endarterectomy and Treatment for Chronic Thromboembolic Pulmonary Hypertension Abstract. Chronic thromboembolic pulmonary hypertension is a relatively rare disease which mostly evolves as a complication of acute pulmonary embolism resulting from the fibrotic organization of residual thrombotic material despite adequate anticoagulation leading to precapillary pulmonary hypertension and persistence of its symptoms. The elevated pulmonary vascular resistance leads to right ventricular heart failure, its symptoms and reduced prognosis. The therapy of choice is the pulmonary endarterectomy, which leads to a reduction of symptoms, optimization of the hemodynamics and improved prognosis. Misdiagnosis and delayed referral often lead to disease progression along with poor surgical outcome. In case of more distal, surgically non-accessible disease, treatment consists of balloon pulmonary angioplasty and pulmonary vasodilator drugs.

Long-term Outcomes and Predictors of Chronic Thromboembolic Pulmonary Hypertension After Pulmonary Endarterectomy

BACKGROUND

Pulmonary endarterectomy (PEA) is the preferred treatment for CTEPH patients which can significantly improve symptoms and pulmonary hemodynamics. Therefore, this retrospective study evaluated the long-term outcomes after pulmonary endarterectomy (PEA) and analyze the predictors of long-term outcomes for chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

From 2002-2020, 76 CTEPH patients successfully discharged after PEA in Beijing Chaoyang Hospital were followed-up by scheduled clinical visits or telephone interviews. The follow-up time lasted for 18 years and median time was 7.29 years.

RESULTS

The survival rate at 1,3,5,10,15 years postoperatively was 100.00%, 97.10%, 95.40%, 89.80% and 82.90%, respectively. Multivariate logistics regression analysis showed that postoperative mPAP (hazard ratio: 1.144; 95%confidence interval: 1.018-1.285; P = 0.023) was associated with a higher risk of late death, right atrium right and left diameters (hazard ratio: 1.113; 95%confidence interval, 1.006-1.231; P = 0.038) were associated with a higher risk of major adverse events.

CONCLUSION

Pulmonary endarterectomy is an effective way to treat CTEPH. Long-term outcome is excellent for patients who undergoing pulmonary endarterectomy who survived from peri-operation time. Postoperative mPAP is a significant prognostic factor for long-term death and right atrium right and left diameters is a significant prognostic factor for major adverse events. That shows patients with high postoperative mPAP and right atrium right and left diameter should be followed up closely.

Preoperative pulmonary vascular resistance and neutrophil-to-lymphocyte ratio predict the demand of extracorporeal membrane oxygenation after pulmonary endarterectomy

BACKGROUND

Acute respiratory and circulatory collapse might occasionally happen after pulmonary endarterectomy (PEA). We aimed to investigate the utilization of extracorporeal membrane oxygenation (ECMO) after PEA and potential risk factors.

METHODS

Demographic characteristics, clinical and surgical data were collected for all patients who underwent PEA from December 2016 to June 2022. All factors were compared between patients in the ECMO group and those in the other group. The most characteristic risk factors were obtained by least absolute shrinkage and selection operator regression and support vector machine machine learning, and receiver operating characteristics (ROC) Curve analysis was performed to verify the diagnostic value of the obtained risk factors.

RESULTS

A total of 117 patients underwent PEA, and 8 (6.8%) of them received ECMO treatment intraoperatively or postoperatively. There were significant differences between the two groups in terms of cardiac function, pulmonary vascular resistance (PVR), preoperative inflammation and cardiopulmonary bypass time. The PVR and neutrophil-to-lymphocyte ratio (N/L ratio) were the most characteristic risk factors with an area under the ROC curve of 0.847 (95% confidence interval [CI] = 0.7517-0.9420, p = .005) and 0.896 (95% CI = 0.803-0.989, p = .001), respectively. The ECMO group had higher PVR (1549.4 ± 600.7 vs. 952.9 ± 466.9 dyn.s.cm^-5 , p = .004) and N/L ratio (6.3 ± 5.6 vs. 2.4 ± 1.7, p = .001).

CONCLUSIONS

PVR and N/L ratio can correctly predict who is likely to receive ECMO treatment after PEA. Therefore, addressing the preoperative inflammatory status might be beneficial but further research is needed.

Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension: A Systematic Review of the Most Updated Literature

Pulmonary endarterectomy (PEA) is the treatment of choice in case of chronic thromboembolic pulmonary hypertension (CTEPH). PEA is performed by an increasing number of surgeons; however, the reported outcomes are limited to a few registries or to individual centers' experiences. This systematic review focuses on pre-operative evaluation, intra-operative procedure and post-operative results in patients submitted to PEA for CTEPH. The literature included was searched using a formal strategy, combining the terms "pulmonary endarterectomy" AND "chronic pulmonary hypertension" and focusing on studies published in the last 5 years (2017-2022) to give a comprehensive overview on the most updated literature. The selection of the adequate surgical candidate is a crucial point, and the decision should always be performed by expert multidisciplinary teams composed of surgeons, pulmonologists and radiologists. In all the included studies, the surgical procedure was performed through a median sternotomy with intermittent deep hypothermic circulatory arrest under cardiopulmonary bypass. In case of residual pulmonary hypertension, alternative combined treatments should be considered (balloon angioplasty and/or medical therapy until lung transplantation in highly selected cases). Short- and long-term outcomes, although not homogenous across the different studies, are acceptable in highly experienced CTEPH centers.

4D flow cardiovascular magnetic resonance recovery profiles following pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension

BACKGROUND

Four-dimensional flow cardiovascular magnetic resonance imaging (4D flow CMR) allows comprehensive assessment of pulmonary artery (PA) flow dynamics. Few studies have characterized longitudinal changes in pulmonary flow dynamics and right ventricular (RV) recovery following a pulmonary endarterectomy (PEA) for patients with chronic thromboembolic pulmonary hypertension (CTEPH). This can provide novel insights of RV and PA dynamics during recovery. We investigated the longitudinal trajectory of 4D flow metrics following a PEA including velocity, vorticity, helicity, and PA vessel wall stiffness.

METHODS

Twenty patients with CTEPH underwent pre-PEA and > 6 months post-PEA CMR imaging including 4D flow CMR; right heart catheter measurements were performed in 18 of these patients. We developed a semi-automated pipeline to extract integrated 4D flow-derived main, left, and right PA (MPA, LPA, RPA) volumes, velocity flow profiles, and secondary flow profiles. We focused on secondary flow metrics of vorticity, volume fraction of positive helicity (clockwise rotation), and the helical flow index (HFI) that measures helicity intensity.

RESULTS

Mean PA pressures (mPAP), total pulmonary resistance (TPR), and normalized RV end-systolic volume (RVESV) decreased significantly post-PEA (P < 0.002). 4D flow-derived PA volumes decreased (P < 0.001) and stiffness, velocity, and vorticity increased (P < 0.01) post-PEA. Longitudinal improvements from pre- to post-PEA in mPAP were associated with longitudinal decreases in MPA area (r = 0.68, P = 0.002). Longitudinal improvements in TPR were associated with longitudinal increases in the maximum RPA HFI (r=-0.85, P < 0.001). Longitudinal improvements in RVESV were associated with longitudinal decreases in MPA fraction of positive helicity (r = 0.75, P = 0.003) and minimum MPA HFI (r=-0.72, P = 0.005).

CONCLUSION

We developed a semi-automated pipeline for analyzing 4D flow metrics of vessel stiffness and flow profiles. PEA was associated with changes in 4D flow metrics of PA flow profiles and vessel stiffness. Longitudinal analysis revealed that PA helicity was associated with pulmonary remodeling and RV reverse remodeling following a PEA.

Clinicopathological Correlation of Chronic Thromboembolic Pulmonary Hypertension: A Retrospective Study

The pathophysiology of chronic thromboembolic pulmonary hypertension (CTEPH) is largely unknown. Although pulmonary endarterectomy (PEA) is potentially curative, inoperable patients and persistent pulmonary hypertension (PH) following surgery remain a significant problem. In this study, we aim to describe the histopathological characteristics of CTEPH and explore the potential relationship between pulmonary arterial lesions, radiological parameters, and clinical manifestations. Endarterectomized tissues from 81 consecutive patients of CTEPH were carefully collected, sectioned, and examined by experienced pathologists. Pertinent clinical and radiological data were obtained from medical records and operative reports. Neointima, fresh/organized thrombi, recanalized regions, and atherosclerotic lesions were microscopically examined as previously described. Thrombi and atherosclerosis were dominant in UCSD classification level I PEA materials, while recanalized neo-vessels were more frequently observed in UCSD classification level III cases. Degenerative changes of the extracellular matrix were also noticed in the vascular bed. Atherosclerotic lesions were more frequently observed in cases with higher ratio of the pulmonary artery diameter to ascending aorta diameter (PA/AA) reflected by computed tomographic pulmonary arterial scanning. Furthermore, the removal of pulmonary artery complex lesions (with the combination of three to four types of lesions) by PEA was associated with lower postoperative mean pulmonary arterial pressure (mPAP) and decreased incidences of persistent PH. Our study demonstrates that the histopathological features of CTEPH are strongly linked with clinical manifestations and the postoperative outcome after PEA. These data may provide possible evidence for further studies in searching for appropriate causal factors underlying this disease.

Mechanical circulatory support devices and treatment strategies for right heart failure

The importance of right heart failure (RHF) treatment is magnified over the years due to the increased risk of mortality. Additionally, the multifactorial origin and pathophysiological mechanisms of RHF render this clinical condition and the choices for appropriate therapeutic target strategies remain to be complex. The recent change in the United Network for Organ Sharing (UNOS) allocation criteria of heart transplant may have impacted for the number of left ventricular assist devices (LVADs), but LVADs still have been widely used to treat advanced heart failure, and 4.1 to 7.4% of LVAD patients require a right ventricular assist device (RVAD). In addition, patients admitted with primary left ventricular failure often need right ventricular support. Thus, there is unmet need for temporary or long-term support RVAD implantation exists. In RHF treatment with mechanical circulatory support (MCS) devices, the timing of the intervention and prediction of duration of the support play a major role in successful treatment and outcomes. In this review, we attempt to describe the prevalence and pathophysiological mechanisms of RHF origin, and provide an overview of existing treatment options, strategy and device choices for MCS treatment for RHF.

Long-term outcomes of combined pulmonary endarterectomy and additional balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

BACKGROUND

The early and long-term outcomes after pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have been established by several high-volume centers, but the impact of postoperative residual pulmonary hypertension affecting postoperative clinical parameters remains unclear. This study aims to investigate the institutional surgical results of PEA and to evaluate the efficacy of additional balloon pulmonary angioplasty (BPA) for residual pulmonary hypertension.

PATIENTS AND METHODS

We retrospectively reviewed 222 patients (57.7 ± 12.9 years old, 141 female) who underwent PEA for CTEPH at the National Cerebral and Cardiovascular Center between 2000 and 2020.

RESULTS

The preoperative mean pulmonary artery pressure (mPAP) was 45.6 ± 9.7 mmHg and pulmonary vascular resistance (PVR) was 1062 ± 451 dyne*sec/cm^-5. Postoperative mPAP (23.4 ± 11 mmHg, 204 patients, P < 0.001) and PVR (419 ± 291 dyne*sec/cm^-5, 199 patients, P < 0.001) significantly improved after PEA. Since 2011, 62 patients (28%) underwent BPA after PEA for "catecholamine dependent" residual PH 1 month after PEA in 14, "scheduled" BPA with residual PH 1 year after PEA in 32, and 16 "symptomatic" patients without residual PH. Their mPAP had significantly improved by PEA (48.1 ± 7.7 to 32.0 ± 10.2 mmHg, P < 0.001), and further improved (33.8 ± 11.1 to 26.5 ± 9.1 mmHg, P < 0.001) after BPA.

CONCLUSIONS

PEA provided immediate and substantial improvements in pulmonary hemodynamics and favorable long-term survival. In addition, postoperative BPA improved postoperative clinical parameters for eligible patients regardless of the presence of residual PH.

Clinical Characteristics of Patients Undergoing Right Heart Catheterizations in Community Hospitals

Background

Recognition of precapillary pulmonary hypertension (PH) has significant implications for patient management. However, the low a priori chance to find this rare condition in community hospitals may create a barrier against performing a right heart catheterization (RHC). This could result in misclassification of PH and delayed diagnosis/treatment of precapillary PH. Therefore, we investigated patient characteristics and echocardiographic parameters associated with the decision whether to perform an RHC in patients with incident PH in 12 Dutch community hospitals.

Methods and Results

In total, 275 patients were included from the OPTICS (Optimizing PH Diagnostic Network in Community Hospitals) registry, a prospective cohort study with patients with incident PH; 157 patients were diagnosed with RHC (34 chronic thromboembolic PH, 38 pulmonary arterial hypertension, 81 postcapillary PH, 4 miscellaneous PH), while 118 patients were labeled as probable postcapillary PH without hemodynamic confirmation. Multivariable analysis showed that older age (>60 years), left ventricular diastolic dysfunction grade 2–3, left atrial dilatation were independently associated with the decision to not perform an RHC, while presence of prior venous thromboembolic events or pulmonary arterial hypertension‐associated conditions, right atrial dilatation, and tricuspid regurgitation velocity ≥3.7 m/s favor an RHC performance.

Conclusions

Older age and echocardiographic parameters of left heart disease were independently associated with the decision to not perform an RHC, while presence of prior venous thromboembolic events or pulmonary arterial hypertension‐associated conditions, right atrial dilation, and severe PH on echocardiography favored an RHC performance. As such, especially elderly patients may be at an increased risk of diagnostic delays and missed diagnoses of treatable precapillary PH, which could lead to a worse prognosis.

Diagnosis, Diagnostic Tools, and Risk Stratification for Contemporary Treatment of Pulmonary Embolism

Pulmonary embolism (PE) is quite common and is associated with significant morbidity and mortality. It is estimated that it is the cause of approximately 100,000 annual deaths in the United States. With great variability in presenting symptoms of PE, poor recognition of PE can be fatal. As such, many risk scores have been created to identify the sickest patients. Choosing the appropriate imaging modality is also critical. Invasive pulmonary angiography was once the gold standard to establish the diagnosis. With the advent of nuclear imaging, V/Q scans, invasive angiography has been phased out for diagnosing acute PE. At present, the standard for diagnosis of acute PE is computed tomography pulmonary angiography. In select patient cohorts, nuclear studies remain the modality of choice. Once the diagnosis of acute PE is established, there is a broad spectrum of severity in outcome which has led to substantial focus and development of risk stratification prediction models. We will discuss making the proper diagnosis with contemporary diagnostic tools and risk stratifying patients with PE to receive the correct treatment.

Balloon pulmonary angioplasty for patients with chronic thromboembolic pulmonary hypertension previously operated by pulmonary endarterectomy

Balloon pulmonary angioplasty improved hemodynamics, walking distance, and World Health Organization functional class in patients with chronic thromboembolic pulmonary hypertension not eligible for pulmonary endarterectomy (Non‐PEA) and patients with persistent pulmonary hypertension after PEA (PEA). More mild complications were observed in PEA‐ compared to Non‐PEA.

Noninvasively predicting pulmonary vascular resistance in chronic thromboembolic pulmonary hypertension

Several echocardiographic methods to estimate pulmonary vascular resistance (PVR) have been proposed. So far, most studies have focused on relatively low PVR in patients with a nonspecific type of pulmonary hypertension. We aimed to clarify the clinical usefulness of a new echocardiographic index for evaluating markedly elevated PVR in chronic thromboembolic pulmonary hypertension (CTEPH). We studied 127 CTEPH patients. We estimated the systolic and mean pulmonary artery pressure using echocardiography (sPAP_Echo, mPAP_Echo) and measured the left ventricular internal diameter at end diastole (LVIDd). sPAP_Echo/LVIDd and mPAP_Echo/LVIDd were then correlated with invasive PVR. Using receiver operating characteristic curve analysis, a cutoff value for the index was generated to identify patients with PVR > 1000 dyn·s·cm⁻⁵. We analyzed pre‐ and postoperative hemodynamics and echocardiographic data in 49 patients who underwent pulmonary endarterectomy (PEA). In this study, mPAP_Echo/LVIDd moderately correlated with PVR (r = 0.51, p < 0.0001). There was a better correlation between PVR and sPAP_Echo/LVIDd (r = 0.61, p < 0.0001). sPAP_Echo/LVIDd ≥ 1.94 had an 77.1% sensitivity and 75.4% specificity to determine PVR > 1000 dyn·s·cm⁻⁵ (area under curve = 0.804, p < 0.0001, 95% confidence interval [CI], 0.66–0.90). DeLong's method showed there was a statistically significant difference between sPAP_Echo/LVIDd with tricuspid regurgitation velocity²/velocity–time integral of the right ventricular outflow tract (difference between areas 0.14, 95% CI, 0.00–0.27). The sPAP_Echo/LVIDd and mPAP_Echo/LVIDd significantly decreased after PEA (both p < 0.0001). The sPAP_Echo/LVIDd and mPAP_Echo/LVIDd reduction rate (ΔsPAP_Echo/LVIDd and ΔmPAP_Echo/LVIDd) was significantly correlated with PVR reduction rate (ΔPVR), respectively (r = 0.58, p < 0.01; r = 0.69, p < 0.05). In conclusion, the index of sPAP_Echo/LVIDd could be a simpler and reliable method in estimating CTEPH with markedly elevated PVR and also be a convenient method of estimating PVR both before and after PEA.

Larger pulmonary artery to ascending aorta ratios are associated with decreased survival of patients undergoing pulmonary endarterectomy

Objectives

The ratio of pulmonary artery (PA) and ascending aorta (AA) diameters has recently been shown to be a useful indicator for disease severity and predictor of outcome in patients with pulmonary hypertension and heart failure. This study aimed at evaluating the applicability of this ratio for perioperative risk assessment of patients with chronic thromboembolic pulmonary hypertension undergoing pulmonary endarterectomy.

Methods

In this retrospective cohort study on 149 patients undergoing pulmonary endarterectomy between 2013 and 2020, the preoperative PA to AA ratio was analyzed on axial computed tomography. Variables of pulmonary hemodynamic status were assessed during preoperative right heart catheterization and postoperative Swan-Ganz catheter measurements. Perioperative survival was analyzed by Kaplan-Meier method and log-rank tests.

Results

Preoperative computed tomography measurements showed a median AA diameter of 31 mm (range, 19-47 mm), and a median PA diameter of 36 mm (range, 25-55 mm). The calculated median PA to AA ratio was 1.13 (range, 0.79-1.80). PA to AA ratio correlated positively with PA pressure (systolic, r = 0.352 [P < .001]; diastolic, r = 0.406 [P < .001]; mean, r = 0.318 [P < .001]) and inversely with age (r = −0.484 [P < .001]). Univariable Cox regression analysis identified PA diameter (P = .008) as a preoperative parameter predictive of survival. There was a significant difference (log-rank P = .037) in 30-day survival probability for patients with lower PA to AA ratios (<1.136; survival probability, 97.4%) compared with patients with higher ratios (>1.136; survival probability, 88.9%).

Conclusions

PA to AA ratio shows a correlation with other variables associated with pulmonary hypertension. In addition, patients with higher PA to AA ratios have lower survival probabilities after PEA. Further analysis of PA to AA ratio on the selection of chronic thromboembolic pulmonary hypertension for different treatment modalities—pulmonary endarterectomy, medical therapy, and or balloon pulmonary angioplasty—is warranted.

Assessment for residual disease after pulmonary endarterectomy in patients with chronic thromboembolic pulmonary hypertension

Objectives

Pulmonary endarterectomy (PEA) is recommended for eligible patients with chronic thromboembolic pulmonary hypertension (CTEPH) and is potentially curative. However, persistent/recurrent CTEPH post-PEA can occur. Here we describe symptom and diagnostic assessment rates for residual disease post-PEA and longitudinal diagnostic patterns before and after riociguat approval for persistent/recurrent CTEPH after PEA.

Methods

This US retrospective cohort study analysed MarketScan data (1 January 2002–30 September 2018) from patients who underwent PEA following a CTEPH/pulmonary hypertension (PH) claim with at least 730 days of continuous enrolment post-PEA. Data on pre-specified PH symptoms and the types and timings of diagnostic assessments were collected.

Results

Of 103 patients (pre-riociguat approval, n=55; post-riociguat approval, n=48), residual PH symptoms >3 months after PEA were reported in 89% of patients. Overall, 89% of patients underwent one or more diagnostic tests (mean 4.6 tests/patient), most commonly echocardiography (84%), with only 5% of patients undergoing right heart catheterisation (RHC). In the post- versus pre-riociguat approval subgroup, assessments were more specific for CTEPH with an approximately two-fold increase in 6-min walk distance and N-terminal prohormone of brain natriuretic protein measurements and ventilation/perfusion scans, and a four-fold increase in RHCs.

Conclusions

Low RHC rates suggest that many patients with PH symptoms post-PEA are not being referred for full diagnostic workup. Changes to longitudinal diagnostic patterns may indicate increased recognition of persistent/recurrent CTEPH post-PEA; however, there remains a need for greater awareness around the importance of continued follow-up for patients with residual PH symptoms post-PEA.

Rates of residual PH symptoms are high after PEA but referral of patients with suspected persistent/recurrent CTEPH following PEA for CTEPH-specific diagnostic assessments is suboptimal, highlighting potential gaps in CTEPH patient care post-PEAhttps://bit.ly/3jfUZlO