Chronic thromboembolic pulmonary hypertension (CTEPH): Updated Recommendations from the Cologne Consensus Conference 2018

Multicenter Standardization of Phase-Resolved Functional Lung MRI in Patients With Suspected Chronic Thromboembolic Pulmonary Hypertension

BACKGROUND

Detection of pulmonary perfusion defects is the recommended approach for diagnosing chronic thromboembolic pulmonary hypertension (CTEPH). This is currently achieved in a clinical setting using scintigraphy. Phase-resolved functional lung (PREFUL) magnetic resonance imaging (MRI) is an alternative technique for evaluating regional ventilation and perfusion without the use of ionizing radiation or contrast media.

PURPOSE

To assess the feasibility and image quality of PREFUL-MRI in a multicenter setting in suspected CTEPH.

STUDY TYPE

This is a prospective cohort sub-study.

POPULATION

Forty-five patients (64 ± 16 years old) with suspected CTEPH from nine study centers.

FIELD STRENGTH/SEQUENCE

1.5 T and 3 T/2D spoiled gradient echo/bSSFP/T2 HASTE/3D MR angiography (TWIST).

ASSESSMENT

Lung signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between study centers with different MRI machines. The contrast between normally and poorly perfused lung areas was examined on PREFUL images. The perfusion defect percentage calculated using PREFUL-MRI (QDPPREFUL) was compared to QDP from the established dynamic contrast-enhanced MRI technique (QDPDCE). Furthermore, QDPPREFUL was compared between a patient subgroup with confirmed CTEPH or chronic thromboembolic disease (CTED) to other clinical subgroups.

STATISTICAL TESTS

t-Test, one-way analysis of variance (ANOVA), Pearson's correlation. Significance level was 5%.

RESULTS

Significant differences in lung SNR and CNR were present between study centers. However, PREFUL perfusion images showed a significant contrast between normally and poorly perfused lung areas (mean delta of normalized perfusion -4.2% SD 3.3) with no differences between study sites (ANOVA: P = 0.065). QDPPREFUL was significantly correlated with QDPDCE (r = 0.66), and was significantly higher in 18 patients with confirmed CTEPH or CTED (57.9 ± 12.2%) compared to subgroups with other causes of PH or with excluded PH (in total 27 patients with mean ± SD QDPPREFUL = 33.9 ± 17.2%).

DATA CONCLUSION

PREFUL-MRI could be considered as a non-invasive method for imaging regional lung perfusion in multicenter studies.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 1.

Case report: Pulmonary artery sarcoma diagnosed through rare brain metastases

We present the case of a 33-year-old male referred across several hospitals because of suspected chronic thromboembolic pulmonary hypertension (CTEPH). Initially admitted in October 2022 for a recurrent, severe cough and diagnosed with CTEPH, he received anticoagulant therapy. However, his symptoms worsened, necessitating a transfer to another facility for thrombolysis treatment. Following an episode of syncope, an MRI scan revealed a metastatic brain tumor. Subsequently, he experienced a third transfer to our hospital, emergency surgery was performed to alleviate cerebral edema and excise a lesion in the left frontal lobe. Postoperative pathology was inconclusive, but a multidisciplinary team meeting, aided by experienced radiologists, eventually confirmed a diagnosis of pulmonary artery sarcoma (PAS) with systemic metastases. This case underscores the necessity of promptly ruling out PAS in patients presenting with significant emboli in the central pulmonary arteries and suggests early referral to specialized centers for suspected cases.

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

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

Nonsurgical treatment of a patient with decompensated right ventricular failure due to chronic thromboembolic pulmonary hypertension with proximal clot location-A case report

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease resulting from impaired patency of the pulmonary arteries by a clot, and the treatment method of choice is pulmonary endarterectomy (PEA). In inoperable patients, balloon pulmonary angioplasty (BPA) is recommended, but we need to implement pharmacological bridge therapy to BPA in some cases. We report a case of a 38-year-old male diagnosed with CTEPH, disqualified from PEA due to comorbidity, who developed right ventricular (RV) failure. The case shows a complex pharmacological treatment method that can be successfully used as an effective bridge therapy to BPA in patients with CTEPH and severe RV dysfunction, disqualified from surgery.

Recovery from kidney failure associated with chronic thromboembolic pulmonary hypertension following pulmonary thomboendarterectomy

The occurrence of renal failure in pulmonary hypertension (PH) is an ominous sign and implies excessive adverse hemodynamic factors. Pharmacologic agents to treat the PH are the mainstay of management, whereas diuretics assist in management of fluid overload. However, when such measures fail, dialysis and ultrafiltration (UF) become necessary to manage progressive azotemia and hypervolemia. Reversal of PH is essential to interrupt this vicious cycle of multisystem failure; otherwise, the need for renal replacement therapy would be permanent.

Venous Thromboembolism: Review of Clinical Challenges, Biology, Assessment, Treatment, and Modeling

Venous thromboembolism (VTE) is a massive clinical challenge, annually affecting millions of patients globally. VTE is a particularly consequential pathology, as incidence is correlated with extremely common risk factors, and a large cohort of patients experience recurrent VTE after initial intervention. Altered hemodynamics, hypercoagulability, and damaged vascular tissue cause deep-vein thrombosis and pulmonary embolism, the two permutations of VTE. Venous valves have been identified as likely locations for initial blood clot formation, but the exact pathway by which thrombosis occurs in this environment is not entirely clear. Several risk factors are known to increase the likelihood of VTE, particularly those that increase inflammation and coagulability, increase venous resistance, and damage the endothelial lining. While these risk factors are useful as predictive tools, VTE diagnosis prior to presentation of outward symptoms is difficult, chiefly due to challenges in successfully imaging deep-vein thrombi. Clinically, VTE can be managed by anticoagulants or mechanical intervention. Recently, direct oral anticoagulants and catheter-directed thrombolysis have emerged as leading tools in resolution of venous thrombosis. While a satisfactory VTE model has yet to be developed, recent strides have been made in advancing in silico models of venous hemodynamics, hemorheology, fluid-structure interaction, and clot growth. These models are often guided by imaging-informed boundary conditions or inspired by benchtop animal models. These gaps in knowledge are critical targets to address necessary improvements in prediction and diagnosis, clinical management, and VTE experimental and computational models.

Pulmonary arterial sarcoma: A case report

RATIONALE

Pulmonary artery sarcoma (PAS) is a rare malignant tumor primarily originating from the pulmonary artery's intima or subintima. Approximately one-third of cases are classified as undifferentiated type. Its clinical manifestations lack specificity, dyspnea is the main symptom but can also present with chest pain, cough, hemoptysis, and other discomforts, making it prone to misdiagnosis as pulmonary embolism (PE).

PATIENT CONCERNS

A 50-year-old woman was admitted to the hospital with "dyspnea for more than 3 months, aggravated for 2 days," and computed tomography pulmonary angiography suggesting "bilateral multiple pulmonary embolisms."

DIAGNOSES

The patient was initially misdiagnosed as PE, and was later definitively diagnosed as undifferentiated pleomorphic sarcoma of the pulmonary artery by pathologic biopsy.

INTERVENTIONS AND OUTCOMES

The patient was initially treated with anticoagulant therapy, but her dyspnea was not relieved. After that, she underwent positron emission computed tomography (PET-CT) and other investigations, which suggested the possibility of PAS, and then she underwent pulmonary endarterectomy to remove the lesion, which relieved her symptoms and was advised to seek further medical attention from the Department of Oncology and Department of Radiotherapy.

LESSONS

PAS can be easily misdiagnosed as PE. If a diagnosis of PE is made, but anticoagulation or even thrombolytic therapy proves ineffective, and there is no presence of PE causative factors such as deep vein thrombosis in the lower extremities, or D-dimer levels are not high, one should be cautious and consider the possibility of PAS.

[Chronic thromboembolic pulmonary hypertension: current diagnostic and treatment options: A review]

The article reviews current approaches to diagnosing and treating chronic thromboembolic pulmonary hypertension (CTEPH). The definition of the CTEPH is given, and its main risk factors are described. It is shown that the modern algorithm of diagnostic search includes four stages; the examination methods used at each stage are characterized. The most rational approach to CTEPH therapy is provided; the possibilities and limitations of pulmonary endarterectomy, transluminal balloon angioplasty of the pulmonary arteries, and specific therapy of pulmonary hypertension in such patients are described. The clinical presentation and treatment of CTEPH according to the Russian Pulmonary Hypertension Registry are reviewed.

Pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension in Cape Town, South Africa

Background

Pulmonary endarterectomy (PEA) is the only definitive and potentially curative therapy for chronic thromboembolic pulmonary hypertension (CTEPH), associated with impressive improvements in symptoms and haemodynamics. However, it is only offered at a few centres in South Africa. The characteristics and outcomes of patients undergoing PEA in Cape Town have not been reported previously.

Objectives

To assess the difference in World Health Organization functional class (WHO-FC) before and at least 6 weeks after surgery.

Methods

We interrogated the adult cardiothoracic surgery database at the University of Cape Town between December 2005 and April 2021 for patients undergoing PEA at Groote Schuur Hospital and a private hospital.

Results

A total of 32 patients underwent PEA, of whom 8 were excluded from the final analysis owing to incomplete data or a histological diagnosis other than CTEPH. The work-up of these patients for surgery was variable: all had a computed tomography pulmonary angiogram, 7 (29%) had a ventilation/perfusion scan, 5 (21%) underwent right heart catheterisation, and none had a pulmonary angiogram. The perioperative mortality was 4/24 (17%): 1 patient (4%) had a cardiac arrest on induction of anaesthesia, 2 patients (8%) died of postoperative pulmonary haemorrhage, and 1 patient (4%) died of septic complications in the intensive care unit. Among the survivors, the median (interquartile range) improvement in WHO-FC was 2 (1 - 3) classes (p=0.0004); 10/16 patients (63%) returned to a normal baseline (WHO-FC I).

Conclusion

Even in a low-volume centre, PEA is associated with significant improvements in WHO-FC and a return to a normal baseline in survivors.

Study synopsis

What the study adds. South African patients undergoing pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have a marked improvement in functional status, with many returning to a normal functional baseline. However, the small number of patients included in this study indicates that PEA is probably underutilised. Pre- and postoperative assessment is inconsistent, despite availability of established guidelines.Implications of the findings. More patients should be referred to specialist centres for assessment for this potentially curative procedure. Use of guidelines to standardise investigations and monitoring of patients with CTEPH may improve patient selection for surgery.

Demographic, clinical, and echocardiographic factors associated with residual perfusion defects beyond six months after pulmonary embolism

BACKGROUND

Residual perfusion defects (RPD) after pulmonary embolism (PE) are common.

PRIMARY AIM

This study aimed to determine the prevalence of RPD in a cohort diagnosed with PE 6-72 months earlier, and to determine demographic, clinical, and echocardiographic variables associated with RPD.

METHODS

Patients aged 18-75 years with prior PE, confirmed by computed tomography pulmonary angiography 6-72 months earlier, were included. Participants (N = 286) completed a diagnostic work-up consisting of transthoracic echocardiography and ventilation/perfusion scintigraphy. Demographic, clinical, and echocardiographic characteristics between participants with RPD and those without RPD were explored in univariate analyses using t-test or Mann-Whitney U test. Multiple logistic regression analysis was used to assess the association between selected variables and RPD.

RESULTS

RPD were detected in 72/286 patients (25.2 %, 95 % CI:20.5 %-30.5 %). Greater tricuspid annular plane systolic excursion (TAPSE) (adjusted odds ratio (aOR) 1.10, 95 % CI:1.00-1.21, p = 0.048) at echocardiographic follow-up, greater thrombotic burden at diagnosis, as assessed by mean bilateral proximal extension of the clot (MBPEC) score 3-4 (aOR 2.08, 95 % CI:1.06-4.06, p = 0.032), and unprovoked PE (aOR 2.25, 95 % CI:1.13-4.48, p = 0.021) were independently associated with increased risk of RPD, whereas increased pulmonary artery acceleration time was associated with a lower risk of RPD (aOR 0.72, 95 % CI:0.62-0.83, p < 0.001, per 10 ms). Dyspnoea was not associated with RPD.

CONCLUSION

RPD were common after PE. Reduced pulmonary artery acceleration time and greater TAPSE on echocardiography at follow-up, greater thrombotic burden at diagnosis, and unprovoked PE were associated with RPD.

Baseline Clinical Characteristics and Incidence of Chronic Thromboembolic Pulmonary Hypertension Patients in Latvia, 2019-2020

Background: Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare and progressive condition; however, the true characteristics of CTEPH are still unknown, as notable regional variations exist in terms of patients' age, baseline hemodynamic data, and management choices. This report aims to investigate the baseline clinical characteristics, incidence, and risk factors associated with CTEPH patients in Latvia from 2019 to 2020. Methods: The data were analyzed from a prospective, nationwide, Latvian pulmonary hypertension registry for incident CTEPH cases. The patients' clinical characteristics were assessed at the time of diagnosis. Results: During the course of this study, a cohort of 13 patients with CTEPH were included for analysis. Among the enrolled CTEPH patients, most exhibited low exercise and functional capacity, with a median (±IQR) 6 min walk distance of 300.0 (±150.0) m. The median values (±IQR) for mean pulmonary artery pressure and pulmonary vascular resistance were 40.0 ± 13.0 mmHg and 7.35 ± 2.82 Wood units, respectively. The most common risk factors for CTEPH were a history of acute pulmonary embolism and a blood group other than O. Conclusions: The findings of this report revealed the characteristics of the Latvian CTEPH population, indicating that a significant proportion of patients are elderly individuals with multiple comorbidities.

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.

Evolving Role and Clinical Evidence in the Global Practice of Balloon Pulmonary Angioplasty

Balloon pulmonary angioplasty (BPA) was first described in 2001 and now has evolved into a class I indication for inoperable or residual chronic thromboembolic pulmonary hypertension. This review article aims to describe evidence from studies performed at various pulmonary hypertension (PH) centers across the globe, to better understand the role of BPA in chronic thromboembolic pulmonary disease with and without PH. Additionally, we hope to highlight innovations and the ever-changing safety and efficacy profile of BPA.

Evaluation of diagnostic accuracy of dual-energy computed tomography in patients with chronic thromboembolic pulmonary hypertension compared to V/Q-SPECT and pulmonary angiogram

Purpose

The relevance of dual-energy computed tomography (DECT) for the detection of chronic thromboembolic pulmonary hypertension (CTEPH) still lies behind V/Q-SPECT in current clinical guidelines. Therefore, our study aimed to assess the diagnostic accuracy of DECT compared to V/Q-SPECT with invasive pulmonary angiogram (PA) serving as the reference standard.

Methods

A total of 28 patients (mean age 62.1 years ± 10.6SD; 18 women) with clinically suspected CTEPH were retrospectively included. All patients received DECT with the calculation of iodine maps, V/Q-SPECT, and PA. Results of DECT and V/Q-SPECT were compared, and the percent of agreement, concordance (utilizing Cohen's kappa), and accuracy (kappa²) to PA were calculated. Furthermore, radiation doses were analyzed and compared.

Results

In total, 18 patients were diagnosed with CTEPH (mean age 62.4 years ± 11.0SD; 10 women) and 10 patients had other diseases. Compared to PA, accuracy and concordance for DECT were superior to V/Q-SPECT in all patients (88.9% vs. 81.3%; k = 0.764 vs. k = 0.607) and in CTEPH patients (82.4% vs. 70.1%; k = 0.694 vs. k = 0.560). Furthermore, the mean radiation dose was significantly lower for DECT vs. V/Q-SPECT (p = 0.0081).

Conclusion

In our patient cohort, DECT is at least equivalent to V/Q-SPECT in diagnosing CTEPH and has the added advantage of significantly lower radiation doses in combination with simultaneous assessment of lung and heart morphology. Hence, DECT should be the subject of ongoing research, and if our results are further confirmed, it should be implemented in future diagnostic PH algorithms at least on par with V/Q-SPECT.

Periprocedural Complications With Balloon Pulmonary Angioplasty: Analysis of Global Studies

BACKGROUND

Balloon pulmonary angioplasty (BPA) was introduced as a treatment modality for patients with inoperable, medically refractory chronic thromboembolic pulmonary hypertension decades ago; however, reports of high rates of pulmonary vascular injury have led to considerable refinement in procedural technique.

OBJECTIVES

The authors sought to better understand the evolution of BPA procedure-related complications over time.

METHODS

The authors conducted a systematic review of original articles published by pulmonary hypertension centers globally and performed a pooled cohort analysis of procedure-related outcomes with BPA.

RESULTS

This systematic review identified 26 published articles from 18 countries worldwide from 2013 to 2022. A total of 1,714 patients underwent 7,561 total BPA procedures with an average follow up of 7.3 months. From the first period (2013-2017) to the second period (2018-2022), the cumulative incidence of hemoptysis/vascular injury decreased from 14.1% (474/3,351) to 7.7% (233/3,029) (P < 0.01); lung injury/reperfusion edema decreased from 11.3% (377/3,351) to 1.4% (57/3,943) (P < 0.01); invasive mechanical ventilation decreased from 0.7% (23/3,195) to 0.1% (4/3,062) (P < 0.01); and mortality decreased from 2.0% (13/636) to 0.8% (8/1,071) (P < 0.01).

CONCLUSIONS

Procedure-related complications with BPA, including hemoptysis/vascular injury, lung injury/reperfusion edema, mechanical ventilation, and death, were less common in the second period (2018-2022), compared with first period (2013-2017), likely from refinement in patient and lesion selection and procedural technique over time.

Frequency and characterization of CTEPH and CTEPD according to the mPAP threshold > 20 mm Hg: Retrospective analysis from data of a prospective PE aftercare program

BACKGROUND

The influence of the new pulmonary hypertension (PH) definition on the incidence of chronic thromboembolic PH (CTEPH) is unclear. The incidence of chronic thromboembolic pulmonary disease without PH (CTEPD) is unknown.

OBJECTIVES

To determine the frequency of CTEPH and CTEPD using the new mPAP cut-off >20 mmHg for PH in patients who have suffered an incidence of pulmonary embolism (PE) and were recruited into an aftercare program.

METHODS

In a prospective two-year observational study based on telephone calls, echocardiography and cardiopulmonary exercise tests, patients with findings suspicious for PH received an invasive work-up. Data from right heart catheterization were used to identify patients with or without CTEPH/CTEPD.

RESULTS

Two years after acute PE (n = 400) we found an incidence of 5.25% for CTEPH (n = 21) and 5.75% for CTEPD (n = 23) according to the new mPAP threshold >20 mmHg. Five of 21 patients with CTEPH and 13 of 23 patients with CTEPD showed no signs of PH in echocardiography. CTEPH and CTEPD subjects showed a reduced VO₂ peak and work rate in cardiopulmonary exercise testing (CPET). The capillary end-tidal CO₂ gradient was comparably elevated in CTEPH and CTEPD, but it was normal in the Non-CTEPD-Non-PH group. According to the PH definition provided by the former guidelines, only 17 (4.25%) patients have been diagnosed with CTEPH and 27 individuals (6.75%) were classified having CTEPD.

CONCLUSIONS

Using mPAP >20 mmHg for diagnosis of CTEPH leads to an increase of 23.5% of CTEPH diagnosis. CPET may help to detect CTEPD and CTEPH.

Pulmonary rehabilitation restores limb muscle mitochondria and improves the intramuscular metabolic profile

BACKGROUND

Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucidated.

METHODS

Sprague-Dawley rats were classified into five groups: non-COPD/rest ( n  = 8), non-COPD/exercise ( n  = 7), COPD/rest ( n  = 7), COPD/medium exercise ( n  = 10), and COPD/intensive exercise ( n  = 10). COPD animals were exposed to cigarette smoke and lipopolysaccharide instillation for 90 days, while the non-COPD control animals were exposed to room air. Non-COPD/exercise and COPD/medium exercise animals were trained on a treadmill at a decline of 5° and a speed of 15 m/min while animals in the COPD/intensive exercise group were trained at a decline of 5° and a speed of 18 m/min. After eight weeks of exercise/rest, we used ultrasonography, immunohistochemistry, transmission electron microscopy, oxidative capacity of mitochondria, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI), and transcriptomics analyses to assess rectal femoris (RF).

RESULTS

At the end of 90 days, COPD rats' weight gain was smaller than control by 59.48 ± 15.33 g ( P  = 0.0005). The oxidative muscle fibers proportion was lower ( P  < 0.0001). At the end of additional eight weeks of exercise/rest, compared to COPD/rest, COPD/medium exercise group showed advantages in weight gain, femoral artery peak flow velocity (Δ58.22 mm/s, 95% CI: 13.85-102.60 mm/s, P  = 0.0104), RF diameters (Δ0.16 mm, 95% CI: 0.04-0.28 mm, P  = 0.0093), myofibrils diameter (Δ0.06 μm, 95% CI: 0.02-0.10 μm, P  = 0.006), oxidative muscle fiber percentage (Δ4.84%, 95% CI: 0.15-9.53%, P  = 0.0434), mitochondria oxidative phosphorylate capacity ( P  < 0.0001). Biomolecules spatial distribution in situ and bioinformatic analyses of transcriptomics suggested COPD-related alteration in metabolites and gene expression, which can be impacted by exercise.

CONCLUSION

COPD rat model had multi-level structure and function impairment, which can be mitigated by exercise.

Differences in disease severity and prognosis of exercise-induced right-to-left shunt between idiopathic pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension patients

Objective

Whether exercise-induced venous-to-systemic shunt (EIS) during cardiopulmonary exercise testing (CPET) has different manifestations or characteristics in idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH) patients remains unknown. We explored the differences in hemodynamics, echocardiography, and prognosis between IPAH and CTEPH patients with and without EIS.

Methods

We conducted a retrospective cross-sectional cohort study and included 161 PH patients at Shanghai Pulmonary Hospital. Demographic, echocardiography, pulmonary hemodynamic, and CPET variables were compared between patients with and without EIS stratified by IPAH and CTEPH. EIS was determined by CPET. Binary logistic regression analyses were performed to explore independent influencing factors of EIS. Cox survival analysis was used to quantify the impact of EIS on the prognosis of patients.

Results

Exercise-induced venous-to-systemic shunt was found in approximately 17.4% of 86 IPAH patients and 20% of 75 CTEPH patients. All-cause mortality occurred in 43 (26.7%) patients during a median follow-up of 6.5 years. Compared with those without EIS, patients with EIS had higher peak end-tidal O₂ and lower VO₂/VE and tricuspid annular plane systolic excursion (TAPSE). Among the IPAH patients, EIS was associated with lower cardiac output, cardiac index, mixed venous oxygen saturation, VO₂/VE, and TAPSE and higher VE/VCO₂ and right ventricular end-diastolic transverse diameter. Logistic regression analysis indicated that VO₂/VE was an independent factor influencing whether IPAH patients developed EIS during CPET. Cox logistic regression indicated that female IPAH patients or IPAH patients with higher VO₂/VE and EIS had a better prognosis. Female IPAH patients had better 10-year survival. In IPAH patients without EIS, patients with higher VO₂/VE had better 10-year survival. However, compared with CTEPH patients without EIS, those with EIS had similar echocardiographic, hemodynamic, CPET parameter results and 10-year survival.

Conclusion

Exercise-induced venous-to-systemic shunt exhibits different profiles among IPAH and CTEPH patients. Among IPAH patients, those with EIS had worse peak end-tidal O₂, VO₂/VE, and TAPSE than those without EIS. VO₂/VE was an independent factor of EIS among IPAH patients. IPAH patients with EIS, female sex or higher VO₂/VE had better survival. However, the association between EIS and PAH severity or prognosis in CTEPH patients needs to be further explored.

Long-term outcome prediction for chronic thromboembolic pulmonary hypertension after pulmonary endarterectomy

BACKGROUND

The definitive treatment for chronic thromboembolic pulmonary hypertension (CTEPH) is pulmonary endarterectomy (PEA), which has good long-term outcomes. However, after surgery, a quarter of the patients still have residual pulmonary hypertension (RPH). In pulmonary hemodynamics, there are no unified criteria for RPH, even though the level may affect long-term survival.

METHODS

Between March 1997 and December 2021, 253 CTEPH patients were treated at our center with PEA. Patients were evaluated retrospectively and classified into early (1997-2014) and late (2015-2021) groups. The clinical characteristics and perioperative outcomes of the two groups were compared, and risk factor analysis for RPH and long-term survival for all cases was performed.

RESULTS

There was no statistically significant difference in demographics between the two groups. However, the Early Group had a significantly higher rate of perioperative death (9.8% vs. 1.2%, p = .001), RPH (48.8% vs. 14.0%, p < .001), and reperfusion pulmonary edema (18.3% vs. 2.9%, p < .001). The median follow-up time was 66.0 months, and overall survival rates at 5, 10, 15, and 18 years after PEA were 91.2%, 83.9%, 64.5%, and 46.0%, respectively. Age and postoperative systolic pulmonary artery pressure (sPAP) were independently related to long-term outcomes in the multivariate Cox analyses. Patients with postoperative sPAP less than 46 mm Hg had a higher chance of survival.

CONCLUSIONS

PEA improved CTEPH hemodynamics immediately and had a positive effect on long-term survival. Patients with postoperative sPAP ≥ 46 mm Hg indicate clinically significant RPH and have a lower long-term survival rate.

Correlation between CT Value on Lung Subtraction CT and Radioactive Count on Perfusion Lung Single Photon Emission CT in Chronic Thromboembolic Pulmonary Hypertension

Background: Lung subtraction CT (LSCT), the subtraction of noncontrast CT from CT pulmonary angiography (CTPA) without spatial misregistration, is easily applicable by utilizing a software-based deformable image registration technique without additional hardware and permits the evaluation of lung perfusion as iodine accumulation, similar to that observed in perfusion lung single photon emission CT (PL-SPECT). The aim of this study was to use LSCT to newly assess the quantitative correlation between the CT value on LSCT and radioactive count on PL-SPECT as a reference and validate the quantification of lung perfusion by measuring the CT value in chronic thromboembolic pulmonary hypertension (CTEPH). Methods: We prospectively enrolled 47 consecutive patients with CTEPH undergoing both LSCT and PL-SPECT; we used noncontrast CT, CTPA, and LSCT to measure CT values and PL-SPECT to measure radioactive counts in areas representing three different perfusion classes—no perfusion defect, subsegmental perfusion defect, and segmental perfusion defect; we compared CT values on noncontrast CT, CTPA, and LSCT and radioactive counts on PL-SPECT among the three classes, then assessed the correlation between them. Results: Both the CT values and radioactive counts differed significantly among the three classes (p < 0.01 for all) and showed weak correlation (ρ = 0.38) by noncontrast CT, moderate correlation (ρ = 0.61) by CTPA, and strong correlation (ρ = 0.76) by LSCT. Conclusions: The CT value measurement on LSCT is a novel quantitative approach to assess lung perfusion in CTEPH and only correlates strongly with radioactive count measurement on PL-SPECT.

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.

Heterogeneity of Lung Density in Patients With Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

RATIONALE AND OBJECTIVES

Pulmonary endarterectomy (PEA) is one of the most effective treatments for chronic thromboembolic pulmonary hypertension (CTEPH). Right heart catheterization (RHC) is the gold standard assessment for pulmonary circulatory dynamics. However, computed tomography (CT) is less invasive than RHC and can elucidate some of the morphological changes caused by thromboembolism. We hypothesized that CT could facilitate the evaluation of heterogeneous pulmonary perfusion. This study investigated whether CT imaging features reflect the disease severity and changes in pulmonary circulatory dynamics in patients with CTEPH before and after PEA.

MATERIALS AND METHODS

This retrospective study included 58 patients with CTEPH who underwent PEA. Pre-PEA and post-PEA CT images were assessed for heterogeneity using CT texture analysis (CTTA). The CT parameters were compared with the results of the RHC and other clinical indices and analyzed with receiver operating characteristic curves analysis for patients with and without residual pulmonary hypertension (PH) (post-PEA mean pulmonary artery pressure ≥ 25 mmHg).

RESULTS

CT measurements reflecting heterogeneity were significantly correlated with mean pulmonary artery pressure. Kurtosis, skewness, and uniformity were significantly lower, and entropy was significantly higher in patients with residual PH than patients without residual PH. Area under the curve values of pre-PEA and post-PEA entropy between patients with and without residual PH were 0.71 (95% confidence interval 0.57-0.84) and 0.75 (0.63-0.88), respectively.

CONCLUSION

Heterogeneity of lung density might reflect pulmonary circulatory dynamics, and CTTA for heterogeneity could be a less invasive technique for evaluation of changes in pulmonary circulatory dynamics in patients with CTEPH undergoing PEA.

Regulation of VWF (Von Willebrand Factor) in Inflammatory Thrombosis

Increasing evidence indicates that inflammation promotes thrombosis via a VWF (von Willebrand factor)-mediated mechanism. VWF plays an essential role in maintaining the balance between blood coagulation and bleeding, and inflammation can lead to aberrant regulation. VWF is regulated on a transcriptional and (post-)translational level, and its secretion into the circulation captures platelets upon endothelial activation. The significant progress that has been made in understanding transcriptional and translational regulation of VWF is described in this review. First, we describe how VWF is regulated at the transcriptional and post-translational level with a specific focus on the influence of inflammatory and immune responses. Next, we describe how changes in regulation are linked with various cardiovascular diseases. Recent insights from clinical diseases provide evidence for direct molecular links between inflammation and thrombosis, including atherosclerosis, chronic thromboembolic pulmonary hypertension, and COVID-19. Finally, we will briefly describe clinical implications for antithrombotic treatment.

The value of ventilation/perfusion scanning and CT pulmonary angiography in predicting chronic thromboembolic pulmonary hypertension after acute pulmonary embolism: a one-year follow-up study

To investigate the value of ventilation/perfusion (V/Q) scanning and CT pulmonary angiography (PA) in predicting CTEPH development after acute pulmonary embolism (APE). This study was performed in APE patients who had undergone both V/Q and CT PA after 3-month anticoagulation. The residual pulmonary obstructions were assessed based on V/Q and CT PA, and then recorded as pulmonary perfusion detect score (PPDs) and CT pulmonary artery obstruction index (PAOI). The predictive performance of PPDs and CT PAOI for CTEPH were determined and risk factors for predicting CTEPH development were identified. A total of 235 patients with initial diagnosis of APE were included in this study. ROC analysis showed that the AUCs of the PPDs and CT PAOI were 0.957 and 0.895, with corresponding cut-off values of 20.50% and 17.50% for predicting CTEPH development. Neither sensitivity nor specificity differed significantly between PPDs and CT PAOI (Sensitivity: 92.00% vs. 80.00%, P = 0.25; Specificity: 88.10% vs. 89.52%, P = 0.69). The univariable and multivariable logistic regression analysis demonstrated that pulmonary arterial hypertension confirmed by echocardiography at initial APE diagnosis (OR: 6.16, 95%CI: 1.31-29.02, P = 0.02), a PPDs of > 20.50% (OR: 22.95, 95%CI: 2.37-222.19, P = 0.007), and a CT PAOI of > 17.50% (OR: 9.98, 95%CI: 2.06-48.49, P = 0.004) were associated with CTEPH development. Both V/Q and CT PA after 3-month anticoagulation for APE showed great performance in predicting CTEPH development, and V/Q scanning has a tendency to be more sensitive but less specific than CT PA. The residual pulmonary embolism detected by V/Q and CT PA was associated with an increased risk of CTEPH development.

Prognostic Relevance of Cardiopulmonary Exercise Testing for Patients with Chronic Thromboembolic Pulmonary Hypertension

Background: Following acute pulmonary embolism (PE), a relevant number of patients experience decreased exercise capacity which can be associated with disturbed pulmonary perfusion. Cardiopulmonary exercise testing (CPET) shows several patterns typical for disturbed pulmonary perfusion. Research question: We aimed to examine whether CPET can also provide prognostic information in chronic thromboembolic pulmonary hypertension (CTEPH). Study Design and Methods: We performed a multicenter retrospective chart review in Germany between 2002 and 2020. Patients with CTEPH were included if they had ≥6 months of follow-up and complete CPET and hemodynamic data. Symptom-limited CPET was performed using a cycle ergometer (ramp or Jones protocol). The association of anthropometric data, comorbidities, symptoms, lung function, and echocardiographic, hemodynamic, and CPET parameters with survival was examined. Mortality prediction models were calculated by Cox regression with backward selection. Results: 345 patients (1532 person-years) were included; 138 underwent surgical treatment (pulmonary endarterectomy or balloon pulmonary angioplasty) and 207 received only non-surgical treatment. During follow-up (median 3.5 years), 78 patients died. The death rate per 1000 person-years was 24.9 and 74.2 in the surgical and non-surgical groups, respectively (p < 0.001). In age- and sex-adjusted Cox regression analyses, CPET parameters including peak oxygen uptake (VO2peak, reflecting cardiopulmonary exercise capacity) were prognostic in the non-surgical group but not in the surgical group. In mortality prediction models, age, sex, VO2peak (% predicted), and carbon monoxide transfer coefficient (% predicted) showed significant prognostic relevance in both the overall cohort and the non-surgical group. In the non-surgical group, Kaplan−Meier analysis showed that patients with VO2peak below 53.4% predicted (threshold identified by receiver operating characteristic analysis) had increased mortality (p = 0.007). Interpretation: The additional measurement of cardiopulmonary exercise capacity by CPET allows a more precise prognostic evaluation in patients with CTEPH. CPET might therefore be helpful for risk-adapted treatment of CTEPH.

Chronic Thromboembolic Pulmonary Hypertension: An Observational Study

Background and Objectives: Chronic thromboembolic pulmonary hypertension (CTEPH) has a high mortality. The treatment of CTEPH could be balloon pulmonary angioplasty (BPA), medical (MT) or pulmonary endarterectomy (PEA). This study aims to assess the clinical characteristics of CTEPH patients, surgically or medically treated, in a pulmonology referral center. Materials and Methods: A total of 124 patients with PH with suspected CTEPH (53 male subjects and 71 female subjects; mean age at diagnosis 67 ± 6) were asked to give informed consent and then were evaluated. The presence of CTEPH was ascertained by medical evaluations, radiology and laboratory tests. Results: After the evaluation of all clinical data, 65 patients met the inclusion criteria for CTEPH and they were therefore enrolled (22 males and 43 females; mean age at diagnosis was 69 ± 8). 26 CTEPH patients were treated with PEA, 32 with MT and 7 with BPA. There was a statistically significant age difference between the PEA and MT groups, at the time of diagnosis, the PEA patients were younger than the MT patients, whereas there was no statistically significant difference in other clinical characteristics (e.g., smoking habit, thrombophilia predisposition), as well as functional and hemodynamic parameters (e.g., 6-min walk test, right heart catheterization). During three years of follow-up, no patients in the PEA groups died; conversely, eleven patients in the MT group died during the same period (p < 0.05). Furthermore, a significant decrease in plasma BNP values and an increase in a meter at the six-minute walk test, 1 and 3 years after surgery, were observed in the PEA group (p < 0.05). Conclusions: This study seems to confirm that pulmonary endarterectomy (PEA) can provide an improvement in functional tests in CTEPH.

Warfarin Failure in a Patient With Chronic Thromboembolic Pulmonary Hypertension: A Case Report and Literature Review

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension caused by chronic venous thromboembolism (VTE). Venous thromboembolism (VTE) manifests as deep vein thrombosis (DVT), progressing to pulmonary embolism (PE). Pulmonary endarterectomy (PEA) is the preferred therapeutic option as it provides vascular disobliteration. Long-term anticoagulation with warfarin or direct oral anticoagulants (DOACs) is recommended for patients at risk for recurrent DVT in poor surgical candidates. However, treatment failure remains a concern. We present a patient who had VTE despite long-term anticoagulation with warfarin who had failed treatment and developed VTE with a therapeutic dilemma to continue anticoagulation despite supratherapeutic international normalized ratio (INR).

Diagnosis of Chronic Thromboembolic Pulmonary Hypertension Using Quantitative Lung Perfusion Parameters Extracted From Dual-energy Computed Tomography Images

PURPOSE

To evaluate quantified iodine mapping parameters in dual-energy computed tomography in normal patients versus those with chronic thromboembolic pulmonary hypertension (CTEPH) with and without pulmonary thromboembolism.

MATERIALS AND METHODS

Using automatically quantified iodine mapping in dual-energy computed tomography, we evaluated lung relative average enhancement, standard deviation (SD), and the SD/lung relative average enhancement ratio. We compared the values for these parameters in normal patients versus those with CTEPH. We also performed a receiver operating characteristic curve analysis to determine the diagnostic cutoffs for the parameters.

RESULTS

Patients constituted 41 patients (10 male [24.4%] and 31 female [75.6%]; mean age [SD]: 70.0 y [13.3]) with CTEPH and 237 (92 male [38.8%] and 145 female [61.2%]; mean age [SD]: 65.9 y [15.9]) normal patients. We found significant differences in lung relative average enhancement (34.9±6.3 vs. 26.9±6.3; P <0.0001), SD (11.6±1.9 vs. 14.7±3.3; P <0.001), and the SD/lung relative average enhancement ratio (33.7±5.0 vs. 55.7±10.4; P <0.001) between the normal and CTEPH groups, respectively. The ROC analyses demonstrated high discriminatory power (area under the curve=0.99) for using the SD/lung relative average enhancement ratio to differentiate between patients in the normal group and CTEPH group. At a threshold for the area under the curve of 44.2, diagnostic sensitivity, specificity, positive predictive value, and negative predictive value for the ratio were 92.7%, 97.5%, 86.5%, and 98.7%, respectively.

CONCLUSIONS

Patients with CTEPH were well-discriminated from normal patients using the SD/lung relative average enhancement ratio.

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.

Chronic thromboembolic pulmonary hypertension: diagnosis, operability assessment and patient selection for pulmonary endarterectomy

Healthcare providers outside pulmonary hypertension (PH) centers having misinformation or insufficient education, and a general lack of treatment awareness contribute to a massive underdiagnosis of chronic thromboembolic pulmonary hypertension (CTEPH), diagnostic delay and refusal of surgery by patients. Together with the subjective operability assessment, this leads to too few patients undergoing pulmonary endarterectomy (PEA); even though this surgery results in improved survival and exercise capacity. Acute pulmonary embolism (PE) survivors should undergo a CTEPH screening strategy. Patients screened positive and those with CTEPH symptoms (with or without history of PE), should undergo transthoracic echocardiography (TTE) to determine the probability of PH. High PH probability patients should undergo a ventilation/perfusion (V/Q) scan. A negative scan rules out CTEPH. Patients with a positive V/Q scan, but also patients with findings suggestive for CTEPH on computed tomography pulmonary angiography (CTPA) to diagnose acute PE, should be referred to a CTEPH center. Further diagnostic work-up currently consists of catheter based pulmonary angiography, CTPA and right heart catheterization. However, new imaging technologies might replace them in the near future, with one single imaging tool to screen, diagnose and assess operability as the ultimate goal. Operability assessment should be performed by a multidisciplinary CTEPH team. PEA surgery should be organized in a single center per country or for each forty to fifty million inhabitants in order to offer the highest level of expertise. Informing patients about PEA should preferably be done by the treating surgeon. Based on the estimated incidence of CTEPH and with a better education of patients and healthcare providers, despite the advent of new interventional and medical therapies for CTEPH, the number of PEA surgeries performed should still have the potential to grow significantly.

Riociguat in Patients with CTEPH and Advanced Age and/or Comorbidities

Riociguat is licensed for the therapy of inoperable chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to investigate whether age and comorbidities influence its tolerability and efficacy. Retrospectively, we analyzed data of tolerability, non-invasive, and invasive efficacy at baseline and follow up (FU) of all patients with CTEPH treated with riociguat at the Department of Internal Medicine V, University of Munich (n = 47), grouping patients according to age (<65 versus 65–79 versus ≥80 years) and risk factors for heart failure with preserved ejection fraction (HFpEF) (<2 versus ≥2 risk factors). During dose titration patients >80 years reported side effects more frequently (40%) than the other age groups (23% and 21% for patients <65 years and patients 65–79, respectively). Cessation of riociguat was rare and occurred independent of age. When looking at the total cohort of 47 patients, three patients stopped therapy and three patients had a reduced maintenance dosage, while 41/47 (87%) and all octogenarians reached the highest maintenance dosage of 7.5 mg/d. The frequency of any side effect was similar in patients in both risk factor groups, and hypotension was only observed in those with <2 risk factors. Parameters of efficacy improved significantly under riociguat treatment. Improvement in 6-min walk distance (6 mwd), N-terminal pro brain natriuretic peptide (Nt-proBNP) and hemodynamics did not differ between age or risk factor groups. In this small real-life cohort, riociguat was well-tolerated and effective in advanced age and risk factors for HFpEF.

Detection of patients with chronic thromboembolic pulmonary hypertension by volumetric iodine quantification in the lung-a case control study

Background

To evaluate whether volumetric iodine quantification of the lung allows for the automatic identification of patients with chronic thromboembolic pulmonary hypertension (CTEPH) and whether the extent of pulmonary malperfusion correlates with invasive hemodynamic parameters.

Methods

Retrospective data base search identified 30 consecutive patients with CTEPH who underwent CT pulmonary angiography (CTPA) on a spectral-detector CT scanner. Thirty consecutive patients who underwent an identical CT examination for evaluation of suspected acute pulmonary embolism and had no signs of pulmonary embolism or PH, served as control cohort. Lungs were automatically segmented for all patients and normal and malperfused volumes were segmented based on iodine density thresholds. Results were compared between groups. For correlation analysis between the extent of malperfused volume and mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) 3 patients were excluded because of a time span of more than 30 days between CTPA and right heart catheterization.

Results

Patients with CTEPH had a higher percentage of malperfused lung compared to controls (43.25%±24.72% vs. 21.82%±20.72%; P=0.001) and showed reduced mean iodine density in malperfused and normal-perfused lung areas, as well as in the vessel volume. Controls showed a left-tailed distribution of iodine density in malperfused lung areas while patients with CTEPH had a more symmetrical distribution (Skew: -0.382±0.435 vs. -0.010±0.396; P=0.004). Patients with CTEPH showed a significant correlation between the percentage of malperfused lung volume and the PVR (r=0.57, P=0.001).

Conclusions

Volumetric iodine quantification helps to identify patients with CTEPH by showing increased areas of malperfusion. The extent of malperfusion might provide a measurement for disease severity in patients with CTEPH.

Systemic sclerosis complicated by chronic thromboembolic pulmonary hypertension treated with balloon pulmonary angioplasty: a case report

Background

Systemic sclerosis (SSc) is known to induce pulmonary hypertension (PH), resulting in poor prognosis. Pulmonary hypertension secondary to connective tissue disease is usually classified as Group 1. In patients with SSc, PH owing to left heart failure (Group 2) and interstitial pneumonia (Group 3) are also known; however, there have been limited reports on chronic thromboembolic PH (CTEPH), which corresponds to Group 4.

Case summary

A 39-year-old female with SSc was admitted with shortness of breath on exertion for the past 4 months. Right heart catheterization revealed severe PH. Group 1 PH secondary to collagen tissue disease was suspected; however, thoracic computed tomography and lung perfusion scan led to the diagnosis of CTEPH of Group 4. We treated the PH with several medications and balloon pulmonary angioplasty (BPA), which improved the PH and right heart failure. Consequently, her overall condition also improved.

Discussion

This is a rare case report of SSc complicated by CTEPH, which was treated with BPA. Patients with SSc are prone to complications of various type of PH. Thus, it is important to distinguish CTEPH in terms of treatment choice and prognosis.

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

RATIONALE

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

OBJECTIVE

To identify the role of VWF in CTEPH.

METHODS

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

MEASUREMENTS AND MAIN RESULTS

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

CONCLUSION

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

Chronic Thromboembolic Pulmonary Hypertension: An Update

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease observed in a small proportion of patients after acute pulmonary embolism (PE). CTEPH has a high morbidity and mortality rate, related to the PH severity, and a poor prognosis, which mirrors the right ventricular dysfunction involvement. Pulmonary endarterectomy (PEA) reduces pulmonary vascular resistance, making it the treatment of choice and should be offered to operable CTEPH patients, as significant symptomatic and prognostic improvement has been observed. Moreover, these patients may also benefit from the advances made in surgical techniques and pulmonary hypertension-specific medication. However, not all patients are eligible for PEA surgery, as some have either distal pulmonary vascular obstruction and/or significant comorbidities. Therefore, surgical candidates should be carefully selected by an interprofessional team in expert centers. This review aims at making an overview of the risk factors and latest developments in diagnostic tools and treatment options for CTEPH.

Systemic-pulmonary collateral supply associated with clinical severity of chronic thromboembolic pulmonary hypertension: a study using intra-aortic computed tomography angiography

OBJECTIVES

To assess whether systemic-pulmonary collaterals are associated with clinical severity and extent of pulmonary perfusion defects in chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

This prospective study was approved by a local ethics committee. Twenty-four patients diagnosed with inoperable CTEPH were enrolled between July 2014 and February 2017. Systemic-pulmonary collaterals were detected using pulmonary vascular enhancement on intra-aortic computed tomography (CT) angiography. The pulmonary enhancement parameters were calculated, including (1) Hounsfield unit differences (HUdiff) between pulmonary trunks and pulmonary arteries (PAs) or veins (PVs), namely HUdiff-PA and HUdiff-PV, on the segmental base; (2) the mean HUdiff-PA, mean HUdiff-PV, numbers of significantly enhanced PAs and PVs, on the patient base. Pulmonary perfusion defects were recorded and scored using the lung perfused blood volume (PBV) based on intravenous dual-energy CT (DECT) angiography. Pearson's or Spearman's correlation coefficients were used to evaluate correlations between the following: (1) segment-based intra-aortic CT and intravenous DECT parameters (2) patient-based intra-aortic CT parameters and clinical severity parameters or lung PBV scores. Statistical significance was set at p < 0.05.

RESULTS

Segmental HUdiff-PV was correlated with the segmental perfusion defect score (r = 0.45, p < 0.01). The mean HUdiff-PV was correlated with the mean pulmonary arterial pressure (PAP) (r = 0.52, p < 0.01), cardiac output (rho = - 0.41, p = 0.05), and lung PBV score (rho = 0.43, p = 0.04). And the number of significantly enhanced PVs was correlated with the mean PAP (r = 0.54, p < 0.01), pulmonary vascular resistance (r = 0.54, p < 0.01), and lung PBV score (rho = 0.50, p = 0.01).

CONCLUSIONS

PV enhancement measured by intra-aortic CT angiography reflects clinical severity and pulmonary perfusion defects in CTEPH.

KEY POINTS

• Intra-aortic CT angiography demonstrated heterogeneous enhancement within the pulmonary vasculature, showing collaterals from the systemic arteries to the pulmonary circulation in CTEPH. • The degree of systemic-pulmonary collateral development was significantly correlated with the clinical severity of CTEPH and may be used to evaluate disease progression. • The distribution of systemic-pulmonary collaterals is positively correlated with perfusion defects in the lung segments in CTEPH.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

ABSTRACT

Chronic thromboembolic pulmonary hypertension (CTEPH) remains significantly underdiagnosed in patients with a history of pulmonary embolism. These patients complain of persistent shortness of breath and present with hypoxemia despite proper anticoagulation. Further investigation reveals evidence of right ventricular dysfunction on echocardiogram, which progresses to right heart failure. CTEPH is associated with a significant increase in patient morbidity and mortality if left untreated. This article offers an approach for the timely recognition of this condition, in addition to suggesting a management protocol with an emphasis on the role of interventional radiology and balloon pulmonary angioplasty.

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

Background

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

Method

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

Discussion

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

Trial registration

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

Cardiac biomarkers as indicators of right ventricular dysfunction and recovery in chronic thromboembolic pulmonary hypertension patients after balloon pulmonary angioplasty therapy - a cardiac magnetic resonance imaging cohort study

Background

In chronic thromboembolic pulmonary hypertension, right heart failure determines outcome. Balloon pulmonary angioplasty therapy allows right heart recovery, which can be monitored by cardiac magnetic resonance imaging. This study evaluates whether cardiac biomarkers (NT-proBNP, MR-proANP, sST2, and PAPP-A) are associated with cardiac magnetic resonance imaging findings prior to and after balloon pulmonary angioplasty therapy.

Methods

This observational cohort study enrolled 22 chronic thromboembolic pulmonary hypertension patients who underwent balloon pulmonary angioplasty therapy and completed a six-month follow-up including cardiac magnetic resonance imaging. Biomarker levels were compared with findings for right heart morphology and function derived from cardiac magnetic resonance imaging.

Results

Pulmonary hemodynamics improved after balloon pulmonary angioplasty therapy [pulmonary vascular resistance: 7.7 (6.0–9.0) vs. 4.7 (3.5–5.5) wood units, p < 0.001; mean pulmonary artery pressure 41 (38–47) vs. 32 (28–37) mmHg, p < 0.001]. Cardiac magnetic resonance imaging findings indicated right heart maladaptation at baseline and recovery after therapy [right ventricular end-diastolic volume 192 (141–229) ml vs. 143 (128–172) ml, p = 0.002; right ventricular end-systolic volume 131 (73–157) ml vs. 77 (61–99) ml (p < 0.001); right ventricular ejection fraction (RVEF) 34 (28–41) % vs. 52 (41–54) %; p < 0.001]. Biomarker level cut-offs [NT-proBNP 347 ng/L (area under the curve (AUC) 0.91), MR-proANP 230 pg/L (AUC 0.78), PAPP-A 14.5 mU/L (AUC 0.81), and sST2 48.0 ng/ml (AUC 0.88)] indicated a RVEF ≤ 35% at baseline. The dynamics of NT-proBNP (rs = −0.79; p < 0.001), MR-proANP (rs = –0.80; p < 0.001), and sST2 (rs = –0.49; p = 0.02) correlated inversely with the improvement in RVEF after therapy. A relative decrease of NT-proBNP < 53% (AUC 0.86) and MR-proANP < 24% (AUC 0.82) indicated a limited RVEF response.

Conclusions

In chronic thromboembolic pulmonary hypertension patients, cardiac magnetic resonance imaging findings illustrate right heart failure and recovery after balloon pulmonary angioplasty therapy. Cardiac biomarker levels correlate with right heart parameters at baseline and their dynamics after therapy.

Chronic thromboembolic pulmonary hypertension: anticoagulation and beyond

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

Neuroprotective effects of dynamic bubble trap use in patients undergoing pulmonary endarterectomy: a two-arm randomized controlled trial

Background

During cardiosurgical procedures that use extracorporeal circulation (ECC), a variety of neurological complications can occur, and postoperative cognitive deficits remain an unsolved problem. Among the sources of these complications are intraoperatively detectable cerebral microemboli, which mainly consist of air. This study's purpose was to assess neuroprotective effects of reducing these gaseous microemboli using a dynamic bubble trap (DBT) in patients undergoing pulmonary endarterectomy (PEA) for the treatment of chronic thromboembolic pulmonary hypertension (CTEPH).

Methods

Patients undergoing PEA were randomly assigned to receive either a DBT (n=47) or no additional device (controls, n=46) during ECC. Neuropsychological testing was performed before and 3 months after PEA. The primary endpoint was cognitive improvement in the DBT group (n=29) compared with the control group (n=42). As secondary endpoint, ischemic brain micro-lesions were analyzed on postoperative days 6 through 10 using diffusion-weighted magnetic resonance imaging (MRI).

Results

Analysis of interaction effects revealed improved performance in visual long-term memory (P=0.008, η²=0.099), verbal long-term memory (P=0.030, η²=0.067), verbal short-term memory (P=0.014, η²=0.083), and attention and processing speed (P=0.043, η²=0.056) from pre- to post-testing in the DBT group compared to control group. In MRI, postoperative ischemic micro-lesions could only be detected in one patient; another patient suffered a severe bihemispheric embolic stroke.

Conclusions

DBT positively influences memory function after PEA. This effect is most likely caused by the reduction of gaseous microemboli.

Trial Registration

This study is registered in the German Clinical Trials Register, ID: DRKS00021499.

Chronic thromboembolic pulmonary hypertension anno 2021

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Venous Thromboembolism for the Practicing Cardiologist

Venous thromboembolism (VTE), encompassing pulmonary embolism (PE) and deep vein thrombosis (DVT), is encountered commonly. Acute PE may present as a high-risk cardiovascular emergency, and acute DVT can cause acute and chronic vascular complications. The goal of this review is to ensure that cardiologists are comfortable managing VTE-including risk stratification, anticoagulation therapy, and familiarity with primary reperfusion therapy. Clinical assessment and determination of degree of right ventricular dysfunction are critical in initial risk stratification of PE and determination of parenteral versus oral anticoagulation therapy. Direct oral anticoagulants have emerged as preferred first-line oral anticoagulation strategy in VTE scenarios.

Ventilation-Perfusion Scan: A Primer for Practicing Radiologists

Lung scintigraphy, or ventilation-perfusion (V/Q) scan, is one of the commonly performed studies in nuclear medicine. Owing to variability in clinical applications and different departmental workflows, many trainees are not comfortable interpreting the results of this study. This article provides a simplified overview of V/Q imaging, including a review of its technique, interpretation methods, and established and emerging clinical applications. The authors review the role of V/Q imaging in evaluation of acute and chronic pulmonary embolism, including the role of SPECT/CT and comparing V/Q scan with CT angiography. In addition, a variety of other applications of pulmonary scintigraphy are discussed, including congenital heart disease, pretreatment planning for lung cancer and emphysema, posttransplant imaging for bronchiolitis obliterans, and less common vascular and nonvascular pathologic conditions that may be detected with V/Q scan. This article will help radiologists and residents interpret the results of V/Q scans and understand the various potential clinical applications of this study. Online supplemental material is available for this article. ^©RSNA, 2021.

Depiction of mosaic perfusion in chronic thromboembolic pulmonary hypertension (CTEPH) on C-arm computed tomography compared to computed tomography pulmonary angiogram (CTPA)

To evaluate mosaic perfusion patterns and vascular lesions in patients with chronic thromboembolic pulmonary hypertension (CTEPH) using C-Arm computed tomography (CACT) compared to computed tomography pulmonary angiography (CTPA). We included 41 patients (18 female; mean age 59.9 ± 18.3 years) with confirmed CTEPH who underwent CACT and CTPA within 21 days (average 5.3 ± 5.2). Two readers (R1; R2) independently evaluated datasets from both imaging techniques for mosaic perfusion patterns and presence of CTEPH-typical vascular lesions. The number of pulmonary arterial segments with typical findings was evaluated and the percentage of affected segments was calculated and categorized: < 25%; 25–49%; 50–75%; < 75% of all pulmonary arterial segments affected by thromboembolic vascular lesions. Inter-observer agreement was calculated for both modalities using the intraclass-correlation-coefficient (ICC). Based on consensus reading the inter-modality agreement (CACT_cons vs. CTPA_cons) was calculated using the ICC. Inter-observer agreement was excellent for central vascular lesions (ICC > 0.87) and the percentage of affected segments (ICC > 0.76) and good for the perceptibility of mosaic perfusion (ICC > 0.6) and attribution of the pattern of mosaic perfusion (ICC > 0.6) for both readers on CACT and CTPA. Inter-modality agreement was excellent for the perceptibility of mosaic perfusion (ICC = 1), the present perfusion pattern (ICC = 1) and central vascular lesions (ICC = 1). However, inter-modality agreement for the percentage of affected segments was fair (ICC = 0.50), with a greater proportion of identified affected segments on CACT_cons. CACT demonstrates a high agreement with CTPA regarding the detection of mosaic perfusion. CACT detects a higher number of peripheral vascular lesions compared to CTPA.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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