Effectiveness of balloon pulmonary angioplasty in patients with inoperable chronic thromboembolic pulmonary hypertension despite having lesion types suitable for surgical treatment

Differential effects of balloon pulmonary angioplasty on chronic thromboembolic pulmonary disease

BACKGROUND

Decreased diffusing capacity of the lungs for carbon monoxide (DLco) is associated with microvascular damage in chronic thromboembolic pulmonary hypertension (CTEPH). Balloon pulmonary angioplasty (BPA) is an effective treatment for CTEPH, but the efficacy of BPA in patients with CTEPH with low DLco remains unclear because BPA does not directly address microvascular damage. This study investigates the influence of microvasculopathy on BPA in CTEPH according to DLco.

METHODS

We retrospectively analysed data from patients with inoperable CTEPH who underwent BPA at the University of Tokyo Hospital from July 2011 to August 2023. The patients were classified into two groups based on their preprocedural DLco (normal DLco (ND) and low DLco (LD) groups), with a DLco cut-off value of 80%. We compared the patient characteristics and effectiveness of BPA between the groups.

RESULTS

Among the 75 patients, 36 were in the LD group. The LD group had a shorter 6-minute walking distance (324±91 vs 427±114 m) than the ND group but the mean pulmonary artery pressure (mPAP) was similar (38.9±7.3 vs 41.1±9.2 mm Hg) before BPA. BPA improved the haemodynamic status and exercise tolerance in both groups. The LD group exhibited a higher mPAP (25.1±7.4 vs 21.5±5.6 mm Hg) and required more sessions of BPA (median 6 vs 4). Based on the analysis of covariance adjusted for baseline values, low DLco significantly correlated with mPAP (sβ=-0.304, 95% CI -7.015 to -1.132, p=0.007) and pulmonary vascular resistance (sβ=-0.324, 95% CI -141.0 to -29.81, p=0.003).

CONCLUSIONS

BPA was associated with an improvement in the haemodynamic status and exercise tolerance in patients with CTEPH even with low DLco. However, low DLco may attenuate the effect of BPA on mPAP and pulmonary vascular resistance and require more treatment sessions.

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Disease: Success Rate and Complications among Different Patient Populations

INTRODUCTION

Balloon pulmonary angioplasty (BPA) is an effective intervention for patients with chronic thromboembolic pulmonary disease (CTEPD). We aimed to identify the patient group with a low success rate or high complication rate of BPA, which is still unclear.

METHODS

Both CTEPD patients with or without pulmonary hypertension (CTEPH and NoPH-CTEPD) were included. CTEPH patients were divided into groups with or without pulmonary endarterectomy (PEA-CTEPH and NoPEA-CTEPH). The efficacy and safety of BPA were compared among the groups.

RESULTS

There were 450, 66, and 41 sessions in the NoPEA-CTEPH, PEA-CTEPH, and NoPH-CTEPD groups, respectively. The success rate (≥1 degree improvement in flow grade) in the PEA-CTEPH group was 94.5%, significantly lower than that in the NoPEA-CTEPH (97.1%) and NoPH-CTEPD (98.4%) groups (p = 0.014). The percentage of complete flow recovery in treated vessels was also lower in PEA-CTEPH group. BPA-related complication rate in NoPEA-CTEPH, PEA-CTEPH, and NoPH-CTEPD patients was 6.1%, 6.0%, and 0.0%, respectively (p = 0.309). One BPA-related death occurred (solely in NoPEA-CTEPH). Mean pulmonary artery pressure ≥41.5 mm Hg was a predictor of BPA-related complications. NoPEA-CTEPH patients had more improvement in 6-min walk distance (6MWD, 87 ± 93 m NoPEA-CTEPH vs. 40 ± 43 m PEA-CTEPH vs. 18 ± 20 m NoPH-CTEPD, p = 0.012).

CONCLUSIONS

BPA was safe and effective for all CTEPD groups with less improvement for the PEA-CTEPH and NoPH-CTEPD groups. The success rate of BPA was lower in the PEA-CTEPH group and the complication rate was lower in the NoPH-CTEPD group. Pre-BPA treatment to lower pulmonary artery pressure should not be overlooked in CTEPD patients.

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

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

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

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

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Safety and efficacy of balloon pulmonary angioplasty for technically operable chronic thromboembolic pulmonary hypertension

Balloon pulmonary angioplasty (BPA) has been proven effective for addressing technically inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, the effectiveness of BPA in technically operable CTEPH patients who, for various reasons, did not undergo the procedure remains an area requiring exploration. This study sought to assess the safety and efficacy of BPA in such cases. We collected and reviewed data from CTEPH patients who underwent BPA in a consecutive manner. Following multidisciplinary team (MDT) decisions, patients were classified into two groups: technically inoperable (group A) and operable (group B). Group B comprised patients deemed technically suitable for pulmonary endarterectomy (PEA) but who did not undergo the procedure for various reasons. All patients underwent a comprehensive diagnostic work-up, including right heart categorization at baseline and the last intervention. This study compared changes in hemodynamic parameters, functional capacity, and quality of life between the two groups. In total, 161 patients underwent 414 procedures at our center, with Group A comprising 112 patients who underwent 282 BPA sessions and group B comprising 49 patients who underwent 132 BPA sessions. Significantly, both groups exhibited improvements in hemodynamics, functional capacity, and quality of life. The occurrence rate of complications, including hemoptysis and lung injury, was similar [12 (63.2%) vs. 7 (36.8%), p = 0.68]. BPA demonstrated favorable outcomes in patients with proximal CTEPH who did not undergo pulmonary endarterectomy. However, the clinical impact of BPA in technically operable CTEPH was found to be less significant than in inoperable cases.

Impact of psychiatric disorders on the hemodynamic and quality of life outcome of balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension: a retrospective study

BACKGROUND

Balloon pulmonary angioplasty (BPA) has beneficial effects on pulmonary hemodynamics, exercise capacity, and quality of life (QOL) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Recently, emerging evidence suggests a relationship between CTEPH and psychiatric disorders (PD). However, data on the clinical efficacy of BPA in CTEPH patients with PD are lacking.

METHODS

We retrospectively analyzed 75 patients with inoperable/residual CTEPH who underwent BPA and right-sided heart catheterization before the initial BPA and within 1 year after the last procedure. QOL was evaluated using the European Quality of Life Five Dimension (EQ-5D) scale in 27 patients before and after BPA sessions. Baseline and post-procedural hemodynamic, functional, and QOL parameters were compared between the patients with and without PD.

RESULTS

Among the 75 participants, 22 (29.3%) patients were categorized in the PD group. Although PD group had a similar mean pulmonary artery pressure level compared with non-PD group (40 ± 7 vs. 41 ± 9 mmHg, p = 0.477), they tended to have unfavorable QOL status (0.63 ± 0.22 vs. 0.77 ± 0.19, p = 0.102). BPA significantly improved pulmonary hemodynamics, laboratory parameters and exercise tolerance in both groups. BPA also significantly improved EQ-5D scores in the non-PD group (from 0.77 ± 0.19 to 0.88 ± 0.13, p < 0.001), but the scores remained unchanged in the PD group (from 0.63 ± 0.22 to 0.67 ± 0.22, p = 0.770). During the long-term period [1,848 (1,055-2,565) days], both groups experienced similar mortality rates (PD 4.6% vs. non-PD 5.7%, p = 1.000).

CONCLUSIONS

BPA improved hemodynamic and functional parameters irrespective of PD, but its effect on QOL was limited in patients with PD.

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension: Clinical Outcomes

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare major vessel pulmonary vascular disease that is characterised by fibrotic obstructions deriving from an organised clot. Recent advances in treatments for CTEPH have significantly improved outcomes. Apart from classical surgical pulmonary endarterectomy, balloon pulmonary angioplasty (BPA) and vasodilator drugs that were tested in randomised controlled trials of non-operable patients are now available. In Europe, CTEPH affects males and females equally. In the first European CTEPH Registry, women with CTEPH underwent pulmonary endarterectomy less frequently than men, especially at low-volume centres. In Japan, CTEPH is more common in females and is predominantly treated by BPA. More data on gender-specific outcomes are expected from the results of the International BPA Registry (NCT03245268).

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension: A Systematic Review and Meta-analysis

PURPOSE

To perform a systematic review and meta-analysis assessing the safety and efficacy of balloon pulmonary angioplasty (BPA) in the treatment of chronic thromboembolic pulmonary hypertension (CTEPH).

MATERIALS AND METHODS

Systematic literature searches were performed from inception to June 2022 to identify studies assessing BPA for CTEPH. Outcomes of interest included the following functional and hemodynamic measures: (a) six-minute walk distance (6MWD), (b) New York Heart Association (NYHA) status, (c) World Health Organization (WHO)-Functional Class status, (d) cardiac index (CI), (e) mean pulmonary artery pressure (mPAP), (f) mean right atrial pressure (mRAP), and (g) pulmonary vascular resistance (PVR). Subgroup analysis was also performed for BPA in post-pulmonary endarterectomy (PEA) patients. All reported BPA-related complications were also recorded. Forty unique studies with a total of 1763 patients were identified for meta-analysis.

RESULTS

All functional and hemodynamic parameters improved significantly following BPA; 6MWD increased 70 m (95% CI 58-82; P < 0.001), NYHA class improved by - 0.9 classes (95% CI - 1.0 to - 0.8; P < 0.001), WHO-FC class improved by - 1 classes ((95% CI - 1.2 to - 0.9; P < 0.001), CI increased 0.26 L/min/m² (95% CI 0.17-0.35; P < 0.001), mPAP decreased - 13.2 mmHg (95% CI - 14.7 to - 11.8; P < 0.001), mRAP decreased - 2.2 mmHg (95% CI - 2.8 to - 1.6; P < 0.001), and PVR decreased - 311 dyne/cm/s^-5 (95% CI - 350 to - 271; P < 0.001). Meta-analysis of patients who underwent BPA for persistent pulmonary hypertension post-PEA demonstrated significant improvements in 6MWD, WHO-FC, PVR and mPAP. Most common complications included lung injury (8.16%), hemoptysis (7.07%) and vessel injury (5.05%).

CONCLUSION

BPA represents a safe and effective treatment option for select individuals with CTEPH with significant improvements in hemodynamic parameters, improved exercise tolerance and a relatively low risk of major complications.

Update on balloon pulmonary angioplasty for treatment of chronic thromboembolic pulmonary hypertension

PURPOSE OF REVIEW

To provide an update on balloon pulmonary angioplasty (BPA) for the treatment of chronic thromboembolic pulmonary hypertension (CTEPH), a pulmonary vascular disease that is characterized by fibro-thrombotic material mechanically obliterating major pulmonary arteries, resulting in increased pulmonary vascular resistance (PVR), progressive pulmonary hypertension (PH) combined with a microscopic pulmonary vasculopathy [1▪▪], right ventricular (RV) failure [2] and premature death.

RECENT FINDINGS

Data from a most recent CTEPH European registry (2015 and 2016) suggest significantly improved survival [3▪] of CTEPH patients compared with survival in the eighties [4], or with data from 2007 and 2009 [5]. Pulmonary endarterectomy (PEA) is still the gold-standard therapy for CTEPH [6,7]. However, only around two thirds of all CTEPH patients are amenable to surgery [3▪,5]. Patients not suitable for PEA and treated conservatively have a poor prognosis [8]. BPA may have a role for this particular group of patients. [9-11]. Currently, BPA programs are available in many countries, with excellent results at expert centers [12-15,16▪,17,18▪▪]. Based on recent data, BPA seems to have a greater impact on symptomatic and hemodynamic improvement than medical therapy with riociguat alone [15].

SUMMARY

The evidence favoring BPA is growing, but there is still a lack of published controlled trials. In addition, treatment concepts including indication, technical performance, use of PH-targeted medication, and the concept of follow-up vary between centers. In addition, there is a significant learning curve impacting outcomes [13]. The data from the International BPA registry will provide answers for some of the open questions.

An unusual case of CTEPH treated by BPA in a patient with a single lung after cancer surgery

A 46-year-old man 1 year after left-sided pneumonectomy for squamous cell lung cancer presented with severely limited exercise tolerance and dyspnea corresponding to World Health Organization functional class IV (WHO Class IV). After right heart catheterization (RHC), mean pulmonary artery pressure (mPAP) was 43 mmHg and pulmonary vascular resistance (PVR) was 10.2 Wood units (WU). Arteriography revealed organized clots located at the proximal level of the right pulmonary artery, leading to a diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). The CTEPH team disqualified the patient from surgical treatment due to high perioperative risk and referred him for balloon pulmonary angioplasty (BPA) together with pulmonary hypertension-specific pharmacotherapy (sildenafil). The patient underwent a cycle of nine BPA sessions and completed treatment without complications. Follow-up showed sustained hemodynamic improvement in RHC (mPAP 23 mmHg, PVR 2.6 WU), improved physical capacity (WHO Class II), and relief of dyspnea symptoms.

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.

Balloon Pulmonary Angioplasty in Technically Operable and Technically Inoperable Chronic Thromboembolic Pulmonary Hypertension

Background: In this study, we aimed to assess the efficacy and safety of balloon pulmonary angioplasty (BPA) in patients with technically inoperable distal-type chronic thromboembolic pulmonary hypertension (d-CTEPH) and technically operable proximal-type disease (p-CTEPH) by analyzing the results of BPA treatment in two collaborating CTEPH referral centers. Methods and results: We assessed hemodynamic results, functional efficacy, complication and survival rate after BPA treatment in 70 CTEPH patients (median age 64 years; (interquartile range (IQR): 52–73 years)), of whom 16 (median age 73 years; (QR 62–82 years)) were in the p-CTEPH subgroup. Altogether, 377 BPA procedures were performed, resulting in significant (p < 0.001) improvement in mean pulmonary artery pressure (mPAP 48.6 ± 10 vs. 31.3 ± 8.6 mmHg), pulmonary vascular resistance (694 ± 296 vs. 333 ± 162 dynes*s*cm⁻⁵), six-minute walk test (365 ± 142 vs. 433 ± 120 metres) and N-terminal pro B-type natriuretic peptide (1307 (510–3294) vs. 206 (83–531) pg/mL). The rate of improvement did not differ between the sub-groups. Lung injury episodes and severe hemoptysis were similarly infrequent in d-CTEPH and p-CTEPH (6.4% vs. 5%; p = 0.55 and 1.0% vs. 2.5; p = 0.24, respectively). There was no significant difference between the sub-groups regarding survival (p = 0.53 by log-rank test). Conclusion: BPA may be beneficial in patients with p-CTEPH who cannot undergo pulmonary endarterectomy (PEA). Larger long-term studies are needed to better define the efficacy, safety, and optimal BPA procedural standards in this population.

Efficacy of shear wave elastography for evaluating right ventricular myocardial fibrosis in monocrotaline-induced pulmonary hypertension rats

BACKGROUND

Right ventricular (RV) function is important for outcomes in pulmonary hypertension. Evaluation of RV myocardial characteristics is useful to assess the disease severity. Shear wave elastography (SWE) provides information of shear wave (SW) elasticity, which is related to tissue hardness, and SW dispersion slope, which reflects tissue viscosity. This study aimed to test the hypothesis that SW elasticity is increased and SW dispersion slope is decreased in the right ventricle of monocrotaline (MCT)-induced pulmonary hypertension rats.

METHODS

Rats were divided into MCT-induced pulmonary hypertension group (n = 10) and control group (n = 10). SW elasticity and SW dispersion slope were measured on excised hearts. Myocardial fibrosis was evaluated histologically.

RESULTS

RV hypertrophy was observed in the MCT group. SW elasticity of right ventricle was higher in the MCT group than in the control group (3.5 ± 0.9 kPa vs. 2.5 ± 0.4 kPa, p < 0.01). SW dispersion slope of right ventricle was lower in the MCT group than in the control group (5.3 ± 1.7 m/s/kHz vs. 7.7 ± 1.5 m/s/kHz, p < 0.01). The fibrosis area of right ventricle was increased in MCT group compared with control group (18 ± 5% vs. 8 ± 3%, p < 0.01), and was positively related to SW elasticity and negatively related to SW dispersion slope.

CONCLUSIONS

Higher SW elasticity and lower SW dispersion slope were observed in the fibrotic myocardium of right ventricle in MCT-induced pulmonary hypertension rats. SWE may have the potential to evaluate RV function by assessing myocardial characteristics.

Balloon pulmonary angioplasty vs. pulmonary endarterectomy in patients with chronic thromboembolic pulmonary hypertension: a systematic review and meta-analysis

Although balloon pulmonary angioplasty (BPA) and pulmonary endarterectomy (PEA) are effective in chronic thromboembolic pulmonary hypertension (CTEPH), the comparison of their efficacy and safety is still unclear. We identified studies through a systematic review of PubMed, Cochrane Library, and Embase and used a random effects meta-analysis model to synthesize estimates of weighted mean differences or combined effect size. In total, 54 studies were included in this meta-analysis. The survival rates at perioperative/in-hospital period, 2 years, and 3 years were 100%, 99%, and 97%, respectively, in BPA group and 93%, 90%, and 88%, respectively, in PEA group. The variation of 6-min walk distance was 141.80 m in BPA and 100.73 m in PEA when the follow-up was 1-6 months. At < 1-month, 1-6-month, and > 12-month follow-up, the changed results of mean pulmonary arterial pressure were - 18.31, - 17.00, and - 12.97 mmHg in BPA group and - 18.93, - 21.21, and - 21.35 mmHg in PEA group. At < 1-month and 1-6-month follow-up, the changed values of pulmonary vascular resistance were - 542.24 and - 599.77 dyne•s•cm^-5 in PEA group and - 443.49 and - 280.00 dyne•s•cm^-5 in BPA group. In addition, there was more wide variety of complications in PEA group than in BPA group. BPA might have higher survival rate (perioperative/in-hospital period, 2-year and 3-year follow-up) and fewer types of complications compared with PEA. The improvement in exercise capacity (1-6-month follow-up) in the BPA group might be more pronounced than in PEA group. Moreover, PEA might be superior in improvement of hemodynamic parameters (< 1-month, 1-6-month, and > 12-month follow-up).

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.

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.