Balloon Pulmonary Angioplasty: A Treatment Option for Inoperable Patients with Chronic Thromboembolic Pulmonary Hypertension

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.

Review of Advances on Management of Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension is rare, underdiagnosed form of pulmonary hypertension. It is caused by intravascular obstruction of pulmonary arteries due to fibrotic transformation of thromboembolic material and microvasculopathy. It is important to diagnose this variant as potentially curative treatment in the form of pulmonary endarterectomy is available. Last two decades have seen rapid advances in targeted medical management and refinement in balloon pulmonary angioplasty technique, which have provided a viable therapeutic option for patients who deemed to be inoperable.

Emerging Role of Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Disease-Insights from the 2022 ESC Guidelines

In this article, we discuss the topic of chronic thromboembolic pulmonary disease (CTEPD) and the growing role of balloon pulmonary angioplasty (BPA) in its treatment. We present the pathophysiology of CTEPD which arises from an incomplete resolution of thrombi in the pulmonary arteries and leads to stenosis and occlusion of the vessels. The article focuses mainly on the chronic thromboembolic pulmonary hypertension (CTEPH) subpopulation for which prognosis is very poor when left untreated. We describe a multimodal approach to treating CTEPH, including pulmonary endarterectomy (PEA), BPA, and pharmacological therapies. Additionally, the benefits of pharmacological pre-treatment before BPA and the technical aspects of the procedure itself are outlined. It is emphasized that BPA does not replace PEA but serves as a complementary treatment option for eligible patients. We summarized efficacy and treatment goals including an improvement in functional and biochemical parameters before and after BPA. Patients who received pre-treatment with riociguat prior to BPA exhibited a notable reduction in the occurrence of less severe complications. However, elderly patients are still perceived as an especially vulnerable group. It is shown that the prognosis of patients undergoing BPA is similar to PEA in the first years after the procedure but the long-term prognosis of BPA still remains unclear. The 2022 ESC/ERS guidelines highlight the significant role of BPA in the multimodal treatment of CTEPH, emphasizing its effectiveness and recommending its consideration as a therapeutic option for patients with CTEPD, both with and without pulmonary hypertension. This review summarizes the available evidence for BPA, patient selection, procedural details, and prognosis and discusses the potential future role of BPA in the management of CTEPH.

Effect of Combination of Balloon Pulmonary Angioplasty and Medical Therapy on Reverse Right Ventricular Remodeling and Hemodynamics in Chronic Thromboembolic Pulmonary Hypertension

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive and debilitating disorder that results from incomplete resolution of vascular obstructions resulting in pulmonary hypertension. Surgical pulmonary thromboendarterectomy (PTE) is the treatment of choice for CTEPH. Unfortunately, many CTEPH patients are ineligible for PTE or do not have access to an expert surgical center. Medical therapy imparts important symptomatic and exercise benefits for CTEPH patients, but it does not extend survival. Balloon pulmonary angioplasty (BPA) is an emerging transcatheter approach that is both safe and efficacious. However, the potential synergy between upfront BPA and medical therapy treatment approaches in patients with inoperable CTEPH is unknown. Here, we evaluated how the combination of BPA and medical therapy compared to medical therapy alone in a newly established BPA program.

METHODS

Twenty-one patients with inoperable or residual CTEPH were evaluated in this single-center observational study. Ten patients underwent upfront BPA and medical therapy while 11 patients were treated with medical therapy alone. Hemodynamic and echocardiographic assessments were performed at baseline and at least 1 month after completion of therapy. Continuous variables were compared using t-test or Mann-Whitney U-test. Categorical variables were analyzed with Chi squared and Fisher's exact test where appropriate.

RESULTS

Combination therapy significantly reduced mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR), but medical therapy only significantly lowered PVR. Comprehensive echocardiographic analysis revealed a more robust reverse right ventricular (RV) remodeling effect and augmentation of RV function with combination therapy. At the end of study, the combination therapy group had lower mPAP and PVR and better RV function. Importantly, there were no significant adverse effects in patients treated with BPA.

CONCLUSION

Combination therapy significantly improves hemodynamics and RV function in inoperable CTEPH while carrying an acceptable risk profile, even in a newly developed program. Further studies comparing upfront combination therapy to medical therapy with larger, long-term, and randomized approaches should be considered.

Treatment of Vascular Injury During Balloon Pulmonary Angioplasty in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background

Treatment strategy for vascular injury during balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) was uncertain.

Objectives

This study aimed to identify an optimal therapeutic strategy for vascular injury during BPA in patients with CTEPH.

Methods

This study reviewed 207 patients with CTEPH and 956 BPA procedures between November 1, 2012 and November 30, 2015. Patients who were diagnosed with vascular injury during BPA, which was defined as angiographic signs or sudden respiratory and hemodynamic defects were included in this study. The study investigated the safety and efficacy of the hierarchically systematic treatment strategy including gelatin sponge embolization (GSE).

Results

More than one-half of the 79 patients and 133 procedures with vascular injury were improved by general treatment with reversal of heparin and high-flow oxygen administration. The investigators performed conventional treatment of proximal vessel occlusion using a guiding or balloon catheter in 47 procedures (35%) in which the culprit vessels could be detected under patients' stable conditions. In 32 procedures (24%) without detected culprit lesions or improvement by conventional treatment, GSE could significantly improve patient condition. The treatment strategy obtained successful bailout in 98% of procedures with vascular injury. No patients who underwent GSE died within 30 days after the treatment. There was no significant difference in cumulative mortality rate (median follow-up: 6.6 years) between groups with or without GSE (15.6% vs 8.2%; adjusted HR: 1.47; 95% CI: 0.25-8.69; P = 0.67).

Conclusions

Treatment strategy including GSE would be promising for vascular injury during BPA in patients with CTEPH.

Cardiopulmonary exercise testing for treatment effect assessment in chronic thromboembolic pulmonary hypertension patients

Aim      To determine possibilities of the cardiopulmonary stress test (CPST) as an unbiassed, noninvasive method for evaluation of the effect of managing patients with chronic thromboembolic pulmonary hypertension (CTEPH).Material and methods  This study included 37 patients with CTEPH, 24 men (mean age, 53±15 years) and 13 women (mean age, 58±8.5 years). The diagnosis was verified and theCoperability was assessed according to 2015 European Society of Cardiology Clinical Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension (PH). The surgical treatment was used in 65 % (n=24) of CTEPH patients: the group with pulmonary thromboendarterectomy constituted 35 % (n=13); the group with balloon pulmonary angioplasty 30% (n=11); and the conservative tactics was used in 27 % (n=10) of patients.Results Baseline CPST parameters significantly correlated with parameters of right heart catheterization (RHC): mixed venous oxygen saturation (SvO2) significantly positively correlated with V´O2peak (r=0.640, p<0.05), V´O2 / heart rate (HR) (r=0.557; p<0.001), PETCO2 peak (r=0.598, p<0.05), and V´E / V´CO2 (r=0.587; p<0.001); cardiac output (CO) correlated with V´O2 / HR (r=0.555, p<0.001), PETCO2peak (r= -0.476; p<0.05 and r=0.555, p<0.001 for ´E / V´CO2). In repeated testing, the physical working capacity (V´O2peak) increased only in patients after the surgical treatment of CTEPH. Importantly in this process, significant correlations remained between a number of CPST and RHC parameters: SvO2 correlated with V´O2peak (r=0.743; p<0.05), V´O2 /HR (r=0.627; p<0.001), PETCO2peak (r=0.538; p<0.05), and V´E / V´CO2 (r=0.597; p<0.001); V´O2 / HR, PETCO2peak, and V´E / V´CO2 significantly correlated with CO (r=0.645, p<0.001; r= -0.516, p<0.001, and r=0.555, p<0.001, respectively.Conclusion      CPST can be used as a noninvasive instrument for evaluation of the effect of CTEPH treatment, particularly in the absence of echocardiographic data for residual PH.

Hospital costs of Balloon Pulmonary Angioplasty (BPA) procedure and management for CTEPH patients: An observational study based on the French national hospital discharge database (PMSI)

Introduction

Since 2014, Balloon Pulmonary Angioplasty (BPA) has become an emerging and complementary strategy for chronic thromboembolic hypertension (CTEPH) patients who are not suitable for pulmonary endarterectomy (PEA) or who have recurrent symptoms after the PEA procedure.

Objective

To assess the hospital cost of BPA sessions and management in CTEPH patients.

Methods

An observational retrospective cohort study of CTEPH-adults hospitalized for a BPA between January 1st, 2014 and June 30th, 2016 was conducted in the 2 centres performing BPA in France (Paris Sud and Grenoble) using the French national hospital discharge database (PMSI-MCO). Patients were followed until 6 months or death, whichever occurred first. Follow-up stays were classified as stays with BPA sessions, for BPA management or for CTEPH management based on a pre-defined algorithm and a medical review using type of diagnosis (ICD-10), delay from last BPA procedure stay and length of stay. Hospital costs (including medical transports) were estimated from National Health Insurance perspective using published official French tariffs from 2014 to 2016 and expressed in 2017 Euros.

Results

A total of 191 patients were analysed; mainly male (53%), with a mean age of 64,3 years. The first BPA session was performed 1.1 years in median (IQR 0.3–2.92) after the first PH hospitalisation. A mean of 3 stays with BPA sessions per patient were reported with a mean length of stay of 8 days for the first stay and 6 days for successive stays. The total hospital cost attributable to BPA was € 4,057,825 corresponding to €8,764±3,435 per stay and €21,245±12,843 per patient. Results were sensitive to age classes, density of commune of residence and some comorbidities.

Conclusions

The study generated robust real-world data to assess the hospital cost of BPA sessions and management in CTEPH patients within its first years of implementation in France.

Chronic thromboembolic pulmonary hypertension: a review

Chronic thromboembolic pulmonary hypertension (CTEPH) is a unique form of pulmonary hypertension resulting from obstruction of the pulmonary artery by fibrotic thromboembolic material, usually initiated by recurrent or incomplete resolution of pulmonary embolism. This distinct form of pulmonary hypertension is classified under Group 4 of the World Health Organization classification. Further investigations are usually initiated, with transthoracic echocardiography followed by right heart catheterisation and pulmonary angiography as the gold standard. Definitive treatment is usually in the form of surgical pulmonary endarterectomy. Inoperable CTEPH is medically treated with pharmacological agents such as phosphodiesterase Type 5 inhibitors, endothelin receptor antagonists, soluble guanylate cyclase stimulators and prostacyclin. Recent developments have made balloon pulmonary angioplasty a viable option as well.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: advances in patient and lesion selection

PURPOSE OF REVIEW

Balloon pulmonary angioplasty (BPA) has been performed worldwide for patients who are ineligible for pulmonary endarterectomy (PEA). However, the technical details of BPA have not been standardized, and no international consensus regarding patient and lesion selection for BPA has been reached. Evidence for the combination of BPA with PEA or medical therapy is also lacking. This review highlights recent progress in BPA in terms of patient and lesion selection and the current procedural approach for BPA, including combination treatment.

RECENT FINDINGS

The indications for BPA have expanded with recent reports describing the improved safety and efficacy of BPA. Because lesions are generally present in all segmental and subsegmental pulmonary arteries, it is recommended to treat all the lesions to achieve desirable hemodynamic improvement. Selective pulmonary angiography is the gold standard for lesion selection in modern BPA aimed at total revascularization. Despite the lack of randomized controlled studies, combination treatment with BPA may be well tolerated and effective.

SUMMARY

BPA, alone or in combination with PEA or medical therapy, may be a treatment option for patients who are not candidates for monotreatment of PEA. However, further investigation is required to standardize patient and lesion selection for BPA.

Advances in balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

Balloon pulmonary angioplasty (BPA) is an emerging treatment option for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who have inoperable, segmental/subsegmental disease, or residual disease after pulmonary endarterectomy. In the past decade, advances in the techniques for BPA have led to better clinical outcomes with improvements in hemodynamics, pulmonary perfusion, exercise tolerance, functional capacity, and quality of life. We present the experience with BPA at our university, the largest CTEPH center in the world, followed by reviewing the published data regarding the efficacy and safety of BPA in patients with CTEPH. There is increasing evidence to support that the initial hemodynamic improvement is sustained for ≥3 years after the procedure. Although infrequent, complications observed with BPA are associated with pulmonary vascular injury or rarely reperfusion pulmonary edema. As the technique for percutaneous pulmonary artery revascularization has improved, the procedural risk and complications have continued to decrease. This promising technique continues to develop, and future research is required to demonstrate the long-term benefits of BPA, standardize the technique, and define a uniform institutional infrastructure for providing BPA as a part of the treatment of CTEPH.

Treatment Strategy Options in Inoperable Chronic Thromboembolic Pulmonary Hypertension Patients

This review presents an analysis of recent publications on the principles of diagnosis and management of patients with chronic thromboembolic pulmonary hypertension (CTEPH). The authors emphasize the importance of patient's operability assessment regarding the possibility of performing pulmonary thrombendarterectomy - a radical treatment option due to complete post-thrombotic material removal from the branches of the pulmonary artery. In the case of an inoperable type of CTEPH, such a method of transcatheter treatment as step-by-step balloon angioplasty of the pulmonary artery (BPA) is proposed. The article clearly outlines the principles of selection, patient training and techniques for BPA. The authors demonstrated their own patented method of the peripheral vascular bed visualization in the case of recanalization of chronic occlusions, which increases the safety of this intervention. Particular attention is paid to hybrid approaches using a soluble guanylate cyclase stimulator, riociguate in combination with BPA for high risk CTEPH patients. The review presents the data of the post hoc analysis of the CHEST-1 study and the data of real clinical practice of the use of riociguat in combination with the endovascular method of treatment on the example of the leading expert groups in Europe, who demonstrated in their studies the positive effect of riociguat on the hemodynamic parameters and the frequency of perioperative complications.

Interventional and pharmacological management of chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is caused by obstruction of the pulmonary vasculature, leading to increased pulmonary vascular resistance and ultimately right ventricular failure, the leading cause of death in non-operated patients. This article reviews the current management of CTEPH. The standard of care in CTEPH is pulmonary endarterectomy (PEA). However, up to 40% of patients with CTEPH are ineligible for PEA, and up to 51% develop persistent/recurrent PH after PEA. Riociguat is currently the only medical therapy licensed for treatment of inoperable or persistent/recurrent CTEPH after PEA based on the results of the Phase III CHEST-1 study. Studies of balloon pulmonary angioplasty (BPA) have shown benefits in patients with inoperable or persistent/recurrent CTEPH after PEA; however, data are lacking from large, prospective, controlled studies. Studies of macitentan in patients with inoperable CTEPH and treprostinil in patients with inoperable or persistent/recurrent CTEPH showed positive results. Combination therapy is under evaluation in CTEPH, and long-term data are not available. In the future, CTEPH may be managed by PEA, medical therapy or BPA - alone or in combination, according to individual patient needs. Patients should be referred to experienced centers capable of assessing and delivering all options.

Novel Balloon Pulmonary Angioplasty Technique for Chronic Thromboembolic Pulmonary Hypertension

This study aimed to clarify the usefulness of the Ikari-curve left (IL) guiding catheter for balloon pulmonary angioplasty (BPA).The current BPA strategy for chronic thromboembolic pulmonary hypertension is dilation of as many branches as possible to normalize hemodynamics and oxygenation. The shape of the guiding catheter is a major factor in achieving this. However, conventional guiding catheters are difficult to introduce into particular branches. The IL guiding catheter may be suitable; however, its utility remains unclear.We retrospectively analyzed 202 consecutive BPA sessions of 40 patients from November 2016 to October 2019 and divided these sessions into two groups: the IL group where the IL guiding catheter was used and the non-IL group where other catheters were utilized. The occurrence of lung injury was determined by the presence of bloody sputum. We compared the rates of successful introduction into target vessels and assessed for the occurrence of lung injury.The average age of enrolled patients was 60.3 ± 14.4 years, with females comprising 65%. There were 99 sessions in the IL group. The median treated branches per session differed between the 2 groups (IL group: 15 versus non-IL group: 10, P < 0.05). The occurrence of lung injury was lower in the IL group (4.0% versus 11.7%, P = 0.07). The IL group had more successful vessel insertions than the non-IL group (78.8% versus 42.7%, P < 0.01).The IL guiding catheter may be introduced into branches that cannot be accessed by conventional guiding catheters.

The evolving role of interventional cardiology in the treatment of pulmonary hypertension

Pulmonary hypertension (PH) is a heterogeneous group of diseases defined by a mean pulmonary arterial pressure greater than 20 mmHg. Clinically, PH is classified into five groups and the group of PH generally defines the cause of PH and the therapeutic options. Currently, medical therapies that target the prostacyclin, endothelin, and nitric oxide pathways are used in pulmonary arterial hypertension and chronic thromboembolic PH (CTEPH) patients. Moreover, surgery can improve outcomes in PH as pulmonary thromboendarterectomy can be curative for CTEPH and lung transplantation is used for end-stage PH. Despite these diverse treatment options, PH patients continue to have high symptom burden and poor long-term outcomes. However, advances in percutaneous technology are opening new avenues for the management of PH. In this review, we discuss the available data supporting the use of four interventional procedures: balloon atrial septostomy, transcatheter Potts shunt, balloon pulmonary angioplasty, and pulmonary artery denervation for the treatment of PH. These procedures provide hemodynamic and functional improvements in PH patients, but they come with their own unique risk profiles. Hopefully, these procedures will continue to be refined and thereby provide a venue for interventional cardiology to safely and effectively improve outcomes for PH moving forward.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: State of the art

Chronic thromboembolic pulmonary hypertension (CTEPH) is a complex chronic disease in which pulmonary artery stenosis or obstruction caused by organized thrombus can lead to increased pulmonary artery pressure and pulmonary vascular resistance, ultimately triggering progressive right heart failure and death. Currently, its exact mechanism is not fully understood. Pulmonary endarterectomy (PEA) has immediate effects with low perioperative mortality and satisfactory prognosis in experienced expert centers for CTEPH patients with proximal lesions. Nevertheless, 37% of patients are deemed unsuitable for PEA surgery due to comorbidities and other factors, and nearly half of the operated patients have residual or recurrent pulmonary hypertension. Riociguat is the only approved drug for CTEPH, although its effect is limited. Balloon pulmonary angioplasty (BPA) is a promising alternative treatment for patients with CTEPH. After more than 30 years of development and refinements, emerging evidence has confirmed its role in patients with inoperable CTEPH or residual/recurrent pulmonary hypertension, with acceptable complications and comparable long-term prognosis to PEA. This review summarizes the pathophysiology of CTEPH, BPA history and development, therapeutic principles, indications and contraindications, interventional procedures, imaging modalities, efficacy and prognosis, complications and management, bridging and hybrid therapies, ongoing clinical trials and future prospects.

Chronic thromboembolic pulmonary hypertension - still evolving

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the leading causes of severe pulmonary hypertension (PH). The disease is still underdiagnosed, and the true prevalence is unknown. CTEPH is characterized by intraluminal non-resolving thrombus organization and fibrous stenosis, or complete obliteration of pulmonary arteries, promoted by progressive remodeling of the pulmonary vasculature. One consequence of this is an increase in pulmonary vascular resistance and pressure, resulting in PH and progressive right heart failure, leading to death if left untreated.

Endovascular disobliteration by pulmonary endarterectomy (PEA) is the preferred treatment for CTEPH patients. PEA surgery is the only technique that can potentially cure CTEPH disease, especially in patients with fresh or organized thrombi of the proximal branches of pulmonary arteries. However, not all patients are eligible for PEA surgery. Recent research has provided evidence suggesting balloon pulmonary angioplasty (BPA) and targeted medical therapy as additional promising available treatments options for inoperable CTEPH and recurrent/persistent PH after PEA surgery.

Studies on BPA have shown it to improve pulmonary hemodynamics, symptoms, exercise capacity and RV function in inoperable CTEPH. Subsequently, BPA has developed into an essential component of the modern era of CTEPH treatment. Large randomized controlled trials have demonstrated varying significant improvements with targeted medical therapy in technically inoperable CTEPH patients. Thus, treatment of CTEPH requires a comprehensive multidisciplinary assessment, including an experienced PEA surgeon, PH specialist, BPA interventionist and CTEPH-trained radiologist at expert centers. In this comprehensive review, we address the latest developments in the fast-evolving field of CTEPH. These include advancements in imaging modalities and developments in operative and interventional techniques, which have widened the range of patients who may benefit from these procedures. The efficacy and safety of targeted medical therapies in CTEPH patients are also discussed. As the treatment options for CTEPH improve, hybrid management involving multiple treatments in the same patient may become a viable option in the near future.

Perfusion Scintigraphy in Diagnosis and Management of Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a life-threatening complication of acute pulmonary embolism (PE). Because the treatment of CTEPH is markedly different from that of other types of pulmonary hypertension, lung ventilation-perfusion (V/Q) scintigraphy is recommended for the workup of patients with unexplained pulmonary hypertension. Lung V/Q scintigraphy is superior to CT pulmonary angiography for detecting CTEPH. Perfusion defect findings of CTEPH can be different from those of acute PE. Familiarity with the patterns of perfusion defects seen during the initial workup of CTEPH and the expected posttreatment changes seen at follow-up imaging is essential for accurate interpretation of V/Q scintigraphy findings. ^©RSNA, 2019.

Imaging of Chronic Thromboembolic Disease

Acute pulmonary embolism (PE) is a leading cause of cardiovascular morbidity. The most common long-term complication of acute PE is chronic thromboembolic disease, a heterogenous entity which ranges from asymptomatic imaging sequelae to persistent symptoms. Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease that can develop in this population and represents the only treatable type of pulmonary hypertension. Recognition of the characteristic findings of chronic pulmonary embolism and CTEPH provides not only diagnostic information, but is also crucial for guiding therapy. The present state-of-the-art review focuses on the multimodality imaging features of chronic pulmonary embolism. Detailed description and illustrations of relevant imaging findings will be demonstrated for ventilation/perfusion (V/Q) scan, CT scan and Dual-Energy CT and MRI and features that distinguish chronic PE from common imaging mimics.

Klippel-Trenaunay syndrome as a rare cause of chronic thromboemboembolic pulmonary hypertension

Klippel-Trenaunay syndrome (KTS) is a congenital disorder characterized by cutaneous capillary malformations, soft tissue and bone hypertrophy, and multiple capillary, venous or lymphatic malformations. KTS is associated with recurrent thromboembolic events. We reported herein five cases of chronic thromboembolic pulmonary hypertension (CTEPH) associated with KTS (age minimum-maximum 26-50 years old, 3 males/2 females). Hemodynamics showed severe pulmonary hypertension (PH) with pulmonary vascular resistance ranging from 5.6 to 18.3 Wood units (WU), associated with marked clinical impairment (NYHA functional class III or IV in 4 patients). Computed tomography (CT) of the chest and pulmonary angiography confirmed proximal CTEPH accessible to surgical intervention in one patient and distal forms of CTEPH in 4 patients. Evolution after pulmonary endarterectomy showed hemodynamic normalization, while the patients with distal CTEPH had severe outcomes with 2 early deaths after PH diagnosis (44 and 35 months respectively). One patient with distal CTEPH was still alive 16 years after diagnosis on specific PH therapy and one was transplanted after 15 years because of right heart failure (death after 12 months). Histological analysis of the lung explants showed typical chronic thromboembolic material specific for CTEPH. In conclusion, KTS may be complicated by severe CTEPH requiring careful anticoagulation and multidisciplinary follow-up in expert centers to screen for disease potentially accessible to endarterectomy. In the modern management era of CTEPH, balloon pulmonary angioplasty will certainly be an interesting option in patients with inoperable disease.

Preoperative balloon pulmonary angioplasty enabled noncardiac surgery of a patient with chronic thromboembolic pulmonary hypertension (CTEPH): A case report

RATIONALE

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease with a poor prognosis, characterized by chronic thromboembolic obstruction of the pulmonary arteries and pulmonary hypertension. Balloon pulmonary angioplasty (BPA) is a newly emergent treatment for CTEPH, which may substitute pulmonary endarterectomy, the standard but more invasive treatment for CTEPH. Here, we report the case of a CTEPH patient who underwent 2 noncardiac surgeries without complications after preoperative intervention of BPA.

PATIENT CONCERNS

A 79-year-old man presented with severe osteoarthritis of bilateral knees, with adaptation of total knee arthroplasty (TKA). Transthoracic echocardiogram revealed severe pulmonary hypertension with estimated right ventricular systolic pressure of 140 mm Hg.

DIAGNOSIS

Pulmonary arteriography revealed total occlusion of the upper branch of the right pulmonary artery, and ventilation/perfusion scan showed multiple mismatched perfusion defects. His pulmonary artery pressure (PAP) was as high as 89/25 (46) mm Hg with normal range of pulmonary capillary wedge pressure. He was diagnosed with CTEPH.

INTERVENTIONS

Four BPA sessions for 8 branches of the bilateral pulmonary arteries were done, until the mean PAP (mPAP) went under 30 mm Hg. For the TKA, we selected spinal anesthesia in order to minimize intraoperative hemodynamic changes. Cardiac surgeons were standby in case extracorporeal membrane oxygenation (ECMO) initiation was required.

OUTCOMES

With appropriate pain management and use of intravenous vasopressors, intraoperative vital signs were stable. No symptoms of hemodynamic collapse were observed postoperatively. The patient was discharged on the 46th postoperative day following rehabilitation. Two years later, left-side unicompartment knee arthroplasty (UKA) was scheduled. Right heart catheterization study revealed the mPAP was 30 mm Hg, nearly the same value as the last study. The operation was performed under spinal anesthesia with continuous arterial pressure monitoring without need for intraoperative vasopressor. He was discharged without complications on the 24th postoperative day.

LESSONS

BPA can be an effective preoperative intervention for CTEPH patients undergoing noncardiac surgery.

Clinical usefulness of right ventricular 3D area strain in the assessment of treatment effects of balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension: comparison with 2D feature-tracking MRI

OBJECTIVES

To evaluate the usefulness of right ventricular (RV) area strain analysis via cardiac MRI (CMRI) as a tool for assessing the treatment effects of balloon pulmonary angioplasty (BPA) in inoperable chronic thromboembolic pulmonary hypertension (CTEPH), RV area strain was compared to two-dimensional (2D) strain with feature-tracking MRI (FTMRI) before and after BPA.

METHODS

We retrospectively analyzed 21 CTEPH patients who underwent BPA. End-systolic global area strain (GAS), longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were measured before and after BPA. Changes in GAS and RV ejection fraction (RVEF) values after BPA were defined as ΔGAS and ΔRVEF. Receiver operating characteristic (ROC) analyses were performed to determine the optimal cutoff of the strain at after BPA for detection of improved patients with decreased mean pulmonary artery pressure (mPAP) less than 30 mmHg and increased RVEF more than 50%.

RESULTS

ROC analysis revealed the optimal cutoffs of strains (GAS, LS, CS, and RS) for identifying improved patients with mPAP < 30 mmHg (cutoff (%) = - 41.2, - 13.8, - 16.7, and 14.4: area under the curve, 0.75, 0.56, 0.65, and 0.75) and patients with RVEF > 50% (cutoff (%) = - 37.2, - 29.5, - 2.9, and 14.4: area under the curve, 0.81, 0.60, 0.56, and 0.56).

CONCLUSIONS

Area strain analysis via CMRI may be a more useful tool for assessing the treatment effects of BPA in patients with CTEPH than 2D strains with FTMRI.

KEY POINTS

• Area strain values can detect improvement of right ventricular (RV) pressure and function after balloon pulmonary angioplasty (BPA) equally or more accurately than two-dimensional strains. • Area strain analysis is a useful analytical method that reflects improvements in complex RV myocardial deformation by BPA. • Area strain analysis is a robust method with reproducibility equivalent to that of 2D strain analysis.

Chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a complication of pulmonary embolism and a major cause of chronic PH leading to right heart failure and death. Lung ventilation/perfusion scintigraphy is the screening test of choice; a normal scan rules out CTEPH. In the case of an abnormal perfusion scan, a high-quality pulmonary angiogram is necessary to confirm and define the pulmonary vascular involvement and prior to making a treatment decision. PH is confirmed with right heart catheterisation, which is also necessary for treatment determination. In addition to chronic anticoagulation therapy, each patient with CTEPH should receive treatment assessment starting with evaluation for pulmonary endarterectomy, which is the guideline recommended treatment. For technically inoperable cases, PH-targeted medical therapy is recommended (currently riociguat based on the CHEST studies), and balloon pulmonary angioplasty should be considered at a centre experienced with this challenging but potentially effective and complementary intervention.

C-Arm computed tomography (CACT)-guided balloon pulmonary angioplasty (BPA): Evaluation of patient safety and peri- and post-procedural complications

AIM

To assess the frequency and severity of complications of balloon pulmonary angioplasty (BPA) using C-arm computed tomography (CACT) guidance.

MATERIAL AND METHODS

266 consecutive interventions in 67 patients (42 females, mean age 66 ± 13 years) were included. Selective CACT was acquired prior to the intervention for three-dimensional (3D) guidance and to select appropriate balloon size based on the measured vessel diameter. Complications during and after the procedure, the need for further interventions and the impact on patient safety and outcome were assessed and categorised according to the SIR Classification System to Complications by Outcome (Grade A-F).

RESULTS

Overall, 237 interventions were conducted without any complications (89.1%). Minor complications not requiring additional treatment occurred during or after 25 procedures (9.4%), including recurring dry cough in four patients during a total of 11 interventions (4.1%) (Grade A), three focal dissections of the targeted pulmonary artery (1.1%), four cases of pulmonary haemorrhage (1.5%), one case of reperfusion oedema (0.4%) and six cases of post-interventional short-term hemoptysis (2.3%) (Grade B). Four cases of major complications requiring additional treatment were observed (1.5%): one case of pulmonary haemorrhage (0.4%) and two cases of post-interventional haemoptysis (0.8%), all resolved after medical therapy without requiring further intervention, and one case of atrial tachycardia induced during catheterisation, subsequently requiring pharmacological cardioversion (0.4%) (Grade C). No fatal or life-threatening peri- or post-interventional complications or mortality were observed (Grade D-F).

CONCLUSION

BPA performed under CACT guidance appears to be a safe procedure with a low risk of severe complications.

KEY POINTS

• CACT guidance of BPA is safe and successful. • CACT-guided BPA procedures have a low complication profile. • CACT guidance is a valuable tool to navigate BPA.

Chronic thromboembolic pulmonary hypertension: emerging endovascular therapy

Chronic thromboembolic pulmonary hypertension (CTEPH) is a debilitating but potentially reversible complication of chronic pulmonary thromboembolic disease characterized by progressive right heart dysfunction secondary to pulmonary arterial stenosis or occlusion. Balloon pulmonary angioplasty (BPA) has recently emerged as an alternative intervention for non-surgical candidates with CTEPH. Modern reperfusion angioplasty techniques relieve sequela of chronic pulmonary hypertension, ameliorate right ventricular failure, and improve functional status. This article will discuss the diagnosis and treatment of patients with CTEPH and the current state of endovascular management with BPA.

After the Dawn - Balloon Pulmonary Angioplasty for Patients With Chronic Thromboembolic Pulmonary Hypertension

In the past 5 years, balloon pulmonary angioplasty (BPA) for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are deemed inoperable has undergone significant refinement. As a result, the procedure is now used worldwide and has become a promising therapeutic option for those patients. However, pulmonary endarterectomy remains the gold standard treatment for patients with CTEPH because the techniques and strategies for BPA are not yet unified. The best therapeutic option for each patient should be determined based on discussion among a multidisciplinary team of experts. For BPA to become an established treatment for CTEPH, further data are needed. This review summarizes the techniques and strategies of BPA at present and discusses the future development of the procedure.

Three-dimensional fractal analysis of 99mTc-MAA SPECT images in chronic thromboembolic pulmonary hypertension for evaluation of response to balloon pulmonary angioplasty: association with pulmonary arterial pressure

OBJECTIVE

Balloon pulmonary angioplasty (BPA) is used for inoperable chronic thromboembolic pulmonary hypertension (CTEPH), but its effect cannot be evaluated noninvasively. We devised a noninvasive quantitative index of response to BPA using three-dimensional fractal analysis (3D-FA) of technetium-99m-macroaggregated albumin (Tc-MAA) single-photon emission computed tomography (SPECT).

PATIENTS AND METHODS

Forty CTEPH patients who underwent pulmonary perfusion scintigraphy and mean pulmonary arterial pressure (mPAP) measurement by right heart catheterization before and after BPA were studied. The total uptake volume (TUV) in bilateral lungs was determined from maximum intensity projection Tc-MAA SPECT images. Fractal dimension was assessed by 3D-FA. Parameters were compared before and after BPA, and between patients with post-BPA mPAP more than 30 mmHg and less than or equal to 30 mmHg. Receiver operating characteristic analysis was carried out.

RESULTS

BPA significantly improved TUV (595±204-885±214 ml, P<0.001) and reduced the laterality of uptake (238±147-135±131 ml, P<0.001). Patients with poor therapeutic response (post-BPA mPAP≥30 mmHg, n=16) showed a significantly smaller TUV increase (P=0.044) and a significantly greater post-BPA fractal dimension (P<0.001) than the low-mPAP group. Fractal dimension correlated with mPAP values before and after BPA (P=0.013 and 0.001, respectively). A post-BPA fractal dimension threshold of 2.4 distinguished between BPA success and failure with 75% sensitivity, 79% specificity, 78% accuracy, and area under the curve of 0.85.

CONCLUSION

3D-FA using Tc-MAA SPECT pulmonary perfusion scintigraphy enables a noninvasive evaluation of the response of CTEPH patients to BPA.

The changing landscape of chronic thromboembolic pulmonary hypertension management

For patients with chronic thromboembolic pulmonary hypertension (CTEPH), the current standard of care involves surgical removal of fibro-thrombotic obstructions by pulmonary endarterectomy. While this approach has excellent outcomes, significant proportions of patients are not eligible for surgery or suffer from persistent/recurrent pulmonary hypertension after the procedure. The availability of balloon pulmonary angioplasty and the approval of the first medical therapy for use in CTEPH have significantly improved the outlook for patients ineligible for pulmonary endarterectomy. In this comprehensive review, we discuss the latest developments in the rapidly evolving field of CTEPH. These include improvements in imaging modalities and advances in surgical and interventional techniques, which have broadened the range of patients who may benefit from such procedures. The efficacy and safety of targeted medical therapies in CTEPH patients are also discussed, particularly the encouraging data from the recent MERIT-1 trial, which demonstrated the beneficial impact of using macitentan to treat patients with inoperable CTEPH, including those on background therapy. As the treatment options for CTEPH improve, hybrid management involving more than one intervention in the same patient may become a viable option in the near future.

Management of CTEPH is evolving rapidly, leading to improved patient outcomeshttp://ow.ly/rHrt30gUQWX

Imaging in Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the potentially curable causes of pulmonary hypertension and is definitively treated with pulmonary thromboendartectomy. CTEPH can be overlooked, as its symptoms are nonspecific and can be mimicked by a wide range of diseases that can cause pulmonary hypertension. Early diagnosis of CTEPH and prompt evaluation for surgical candidacy are paramount factors in determining future outcomes. Imaging plays a central role in the diagnosis of CTEPH and patient selection for pulmonary thromboendartectomy and balloon pulmonary angioplasty. Currently, various imaging tools are used in concert, with techniques such as computed tomography (CT) and conventional pulmonary angiography providing detailed structural information, tests such as ventilation-perfusion (V/Q) scanning providing functional data, and magnetic resonance imaging providing a combination of morphologic and functional information. Emerging techniques such as dual-energy CT and single photon emission computed tomography-CT V/Q scanning promise to provide both anatomic and functional information in a single test and may change the way we image these patients in the near future. In this review, we discuss the roles of various imaging techniques and discuss their merits, limitations, and relative strengths in depicting the structural and functional changes of CTEPH. We also explore newer imaging techniques and the potential value they may offer.

Treatment of Chronic Thromboembolic Pulmonary Hypertension: The Role of Medical Therapy and Balloon Pulmonary Angioplasty

Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially curable disease when treated with pulmonary thromboendarterectomy (PTE). However, even at experienced surgical centers, nearly one-third of patients with CTEPH will be deemed inoperable for reasons including distal disease, comorbidities, or out-of-proportion pulmonary hypertension. It is in these patients with inoperable CTEPH that pulmonary hypertension (PH)-targeted medical therapy and balloon pulmonary angioplasty have potential therapeutic value. Previous unblinded cohort trials have assessed PH-targeted medical therapy in various subpopulations of CTEPH patients using epoprostenol, treprostinil, sildenafil, bosentan, and iloprost, each demonstrating measurable pulmonary hemodynamic effects. However, riociguat, a soluble guanylate cyclase stimulator, is the first FDA-approved therapy for inoperable CTEPH to demonstrate both an improvement in functional capabilities (6-minute walk time) as well as significant gains in secondary pulmonary hemodynamic end points in a large placebo-controlled trial. Balloon pulmonary angioplasty is an interventional procedure using telescoping catheters placed in the pulmonary arteries, through which wires and balloons are used to mechanically disrupt chronic clot material and relieve pulmonary vascular obstruction. Contemporary case series from multiple centers worldwide have demonstrated pulmonary hemodynamic improvement with this approach. As a result of these advances, patients with inoperable CTEPH who had few options as recently as 5 years ago now have alternatives with emerging evidence of therapeutic efficacy.

Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension: New Horizons in the Interventional Management of Pulmonary Embolism

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed potential complication of acute or recurrent pulmonary thromboembolic disease. Multiple studies suggest that up to 5% of patients with acute pulmonary thromboembolic disease go on to develop CTEPH. The prognosis of untreated CTEPH is poor, but advances in medical and surgical treatments over the past few decades have improved patient outcomes. The gold standard and curative treatment for CTEPH is pulmonary endarterectomy; however, some patients are inoperable and others who have undergone pulmonary endarterectomy experience persistent or recurrent pulmonary hypertension despite medical therapy. In recent years, balloon pulmonary angioplasty has emerged as a primary and adjunctive treatment for these CTEPH patients at expert or specialized centers. This review outlines an approach to balloon pulmonary angioplasty for CTEPH, including clinical presentation and evaluation; patient selection and indications; treatment planning; equipment and technique; overcoming technical challenges; recognition and management of complications; postprocedural care and clinical follow-up; and expected outcomes.

Balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is thought to result from incomplete resolution of pulmonary thromboemboli that undergo organisation into fibrous tissue within pulmonary arterial branches, filling pulmonary arterial lumina with collagenous obstructions. The treatment of choice is pulmonary endarterectomy (PEA) in CTEPH centres, which has low post-operative mortality and good long-term survival. For patients ineligible for PEA or who have recurrent or persistent pulmonary hypertension after surgery, medical treatment with riociguat is beneficial. In addition, percutaneous balloon pulmonary angioplasty (BPA) is an emerging option, and promises haemodynamic and functional benefits for inoperable patients. In contrast to conventional angioplasty, BPA with undersized balloons over guide wires exclusively breaks intraluminal webs and bands, without dissecting medial vessel layers, and repeat sessions are generally required. Observational studies report that BPA improves haemodynamics, symptoms and functional capacity in patients with CTEPH, but controlled trials with long-term follow-up are needed. Complications include haemoptysis, wire injury, vessel dissection, vessel rupture, reperfusion pulmonary oedema, pulmonary parenchymal bleeding and haemorrhagic pleural effusions. This review summarises the available evidence for BPA, patient selection, recent technical refinements and periprocedural imaging, and discusses the potential future role of BPA in the management of CTEPH.

Balloon pulmonary angioplasty is an emerging percutaneous vascular intervention for non-operable CTEPHhttp://ow.ly/tIN3309hys3

Medical Therapy Versus Balloon Angioplasty for CTEPH: A Systematic Review and Meta-Analysis

BACKGROUND

A significant number of chronic thromboembolic pulmonary hypertension (CTEPH) patients will have an inoperable disease. Medical therapy and balloon pulmonary angioplasty (BPA) have provided alternate therapeutic options for patients with inoperable CTEPH, although there are a limited number of published studies examining the outcomes. Thus, our study aims to evaluate and compare the efficacy of medical therapy and BPA in patients with inoperable CTEPH.

METHODS

An electronic search of six databases was performed and the search results were screened against established criteria for inclusion into this study. Data was extracted and meta-analytical techniques were used to analyse the data.

RESULTS

Pooled data from RCTs revealed that medical therapy, compared with a placebo, was associated with a significant improvement of at least one functional class (p=0.038). With regards to pulmonary haemodynamics, medical therapy also resulted in a significant reduction in both mean pulmonary arterial pressure (mPAP) (p=0.002) and pulmonary vascular resistance (PVR) (p<0.001). From the included observational studies, the 6-minute walk distance (6MWD) significantly increased following medical therapy by an average of 22.8% (p<0.001). The pooled improvement in 6MWD was found to be significantly higher in the BPA group when compared to medical therapy for CTEPH (p=0.001). Pooled data from available observational studies of medical therapy or BPA all demonstrated significant improvements in mPAP and PVR for pre versus post intervention comparisons. The improvement in mPAP (p=0.002) and PVR (p=0.002) were significantly greater for BPA intervention when compared to medical therapy.

CONCLUSIONS

High-quality evidence supports the use of targeted medical therapy in improving haemodynamics in patients with inoperable CTEPH. There is only moderate-quality evidence from observational studies supporting the efficacy of BPA in improving both haemodynamics and exercise capacity. Further RCTs and prospective observational studies comparing medical therapy and BPA in patients with inoperable CTEPH are required.

Chronic Embolic Pulmonary Hypertension Caused by Pulmonary Embolism and Vascular Endothelial Growth Factor Inhibition

Our understanding of the pathophysiological basis of chronic thromboembolic pulmonary hypertension (CTEPH) will be accelerated by an animal model that replicates the phenotype of human CTEPH. Sprague-Dawley rats were administered a combination of a single dose each of plastic microspheres and vascular endothelial growth factor receptor antagonist in polystyrene microspheres (PE) + tyrosine kinase inhibitor SU5416 (SU) group. Shams received volume-matched saline; PE and SU groups received only microspheres or SU5416, respectively. PE + SU rats exhibited sustained pulmonary hypertension (62 ± 13 and 53 ± 14 mmHg at 3 and 6 weeks, respectively) with reduction of the ventriculoarterial coupling in vivo coincident with a large decrement in peak rate of oxygen consumption during aerobic exercise, respectively. PE + SU produced right ventricular hypokinesis, dilation, and hypertrophy observed on echocardiography, and 40% reduction in right ventricular contractile function in isolated perfused hearts. High-resolution computed tomographic pulmonary angiography and Ki-67 immunohistochemistry revealed abundant lung neovascularization and cellular proliferation in PE that was distinctly absent in the PE + SU group. We present a novel rodent model to reproduce much of the known phenotype of CTEPH, including the pivotal pathophysiological role of impaired vascular endothelial growth factor-dependent vascular remodeling. This model may reveal a better pathophysiological understanding of how PE transitions to CTEPH in human treatments.

Chronic thromboembolic pulmonary hypertension, pregnancy, and a pulmonary endarterectomy: a rare challenge

It is well described that patients with group 1 forms of pulmonary arterial hypertension have a high risk of mortality during pregnancy and in the early postpartum period. However, to the authors' knowledge, the diagnosis and management of group 4 pulmonary hypertension due to chronic thromboembolic pulmonary hypertension (CTEPH) during pregnancy with early postpartum pulmonary endarterectomy (PEA) has not been previously reported. We report the case of a 28-year-old woman who received a diagnosis of CTEPH during her pregnancy, was managed as an inpatient by a multidisciplinary team throughout the pregnancy and early postpartum period, and underwent PEA 6 weeks after delivery. While the management of acute pulmonary embolus in pregnancy is well described, this unique case of CTEPH diagnosed during pregnancy illustrates several challenging management issues.