Clinical differences between children and adults with idiopathic and heritable pulmonary arterial hypertension.

BACKGROUND: Although previous studies have demonstrated that paediatric pulmonary arterial hypertension remains distinct from that in adults, there are limited studies evaluating a direct comparison between children and adults. The aim of this head-to-head comparison study was to compare the gender, haemodynamic parameters, and prognosis between paediatric and adult pulmonary arterial hypertension. METHODS AND RESULTS: We retrospectively assessed the clinical differences in 40 childhood-onset (under 20 years old) patients and 40 adult-onset patients with idiopathic and heritable pulmonary arterial hypertension who were followed up at two centres. There was no female predominance among patients with childhood-onset pulmonary arterial hypertension (child female: 42.5%, adult female: 80%). The percent of New York Heart Association functional class IV in adult-onset pulmonary arterial hypertension tended to be higher than those in childhood-onset pulmonary arterial hypertension (22.5 and 10%, respectively), although children had worse haemodynamic parameters at diagnosis (mean pulmonary artery pressure (children versus adults); median 65 mmHg versus 49 mmHg, p < 0.001). There was no significant difference in the event-free survival rate between the two groups (95% vs. 85%) during the follow-up period (median, 96 months; range, 1-120 months). CONCLUSIONS: Although paediatric pulmonary arterial hypertension patients had worse haemodynamic parameters at diagnosis than adults, children survived as long as adults with appropriate therapeutic strategies.

Selexipag for the treatment of chronic thromboembolic pulmonary hypertension.

BACKGROUND: Treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) remain limited. Selexipag, an oral selective IP prostacyclin receptor agonist approved for pulmonary arterial hypertension, is a potential treatment option for CTEPH. METHODS: In this multicentre, randomised, double-blind, placebo-controlled study, 78 Japanese patients with inoperable CTEPH or persistent/recurrent pulmonary hypertension after pulmonary endarterectomy and/or balloon pulmonary angioplasty were randomly assigned to receive placebo or selexipag. The primary end-point was the change in pulmonary vascular resistance (PVR) from baseline to week 20. Secondary end-points were changes in other haemodynamic parameters: 6-min walk distance (6MWD), Borg dyspnoea scale score, World Health Organization (WHO) functional class, EuroQol five-dimension five-level tool and N-terminal pro-brain natriuretic peptide. RESULTS: The change in PVR was -98.2±111.3 dyn·s·cm-5 and -4.6±163.6 dyn·s·cm-5 in the selexipag and placebo groups, respectively (mean difference -93.5 dyn·s·cm-5; 95% CI -156.8 to -30.3; p=0.006). The changes in cardiac index (p<0.001) and Borg dyspnoea scale score (p=0.036) were also significantly improved over placebo. 6MWD and WHO functional class were not significantly improved. The common adverse events in the selexipag group corresponded to those generally observed following administration of a prostacyclin analogue. CONCLUSION: Selexipag significantly improved PVR and other haemodynamic variables in patients with CTEPH, although exercise capacity remained unchanged. Further large-scale investigation is necessary to prove the role of selexipag in CTEPH.

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

PURPOSE OF REVIEW: Balloon pulmonary angioplasty (BPA) has been performed worldwide for patients who are ineligible for pulmonary endarterectomy (PEA). However, the technical details of BPA have not been standardized, and no international consensus regarding patient and lesion selection for BPA has been reached. Evidence for the combination of BPA with PEA or medical therapy is also lacking. This review highlights recent progress in BPA in terms of patient and lesion selection and the current procedural approach for BPA, including combination treatment. RECENT FINDINGS: The indications for BPA have expanded with recent reports describing the improved safety and efficacy of BPA. Because lesions are generally present in all segmental and subsegmental pulmonary arteries, it is recommended to treat all the lesions to achieve desirable hemodynamic improvement. Selective pulmonary angiography is the gold standard for lesion selection in modern BPA aimed at total revascularization. Despite the lack of randomized controlled studies, combination treatment with BPA may be well tolerated and effective. SUMMARY: BPA, alone or in combination with PEA or medical therapy, may be a treatment option for patients who are not candidates for monotreatment of PEA. However, further investigation is required to standardize patient and lesion selection for BPA.

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

BACKGROUND: The number of successfully recanalized total occlusions affects hemodynamic improvement after balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to clarify the current efficacy, patency, and success rate of BPA for total occlusions. METHODS: Between April 2016 and August 2021, 178 BPAs were performed in 100 patients with CTEPH and total occlusions. The primary success and subsequent patency rates immediately before the second BPA procedure (follow-up) were compared between the segmental and subsegmental groups, based on the flow grade, which was defined as follows: 0, no reperfusion; 1, minimal reperfusion; 2, partial reperfusion; and 3, complete reperfusion. RESULTS: Total occlusions were mainly located in the right lung (70%) and lower lobes (48%). The primary success rate was 88%, with significant improvements in oxygenation, hemodynamic parameters, and 6-minute walk test. The primary flow grade did not differ between groups. However, the proportion of lesions with a flow grade of 2 or 3 at follow-up was significantly higher in the subsegmental group than in the segmental group (84% vs 45%, respectively; P < 0.01). In multivariate analysis, flow grade in the acute phase (odds ratio [OR], 46.9; 95% confidence interval [CI], 12.54-176.78; P < 0.01) and subsegmental lesions (OR, 13.8; 95% CI, 3.24-58.94; P < 0.01) were independently associated with better patency (flow grade of 2 or 3) at follow-up. CONCLUSIONS: Total occlusions can be safely and effectively treated with BPA. BPA for total occlusions may be preferable for subsegmental over segmental lesions.

Effects of medical therapy and age on cardiac output changes following balloon pulmonary angioplasty: Implications for combination therapy in chronic thromboembolic pulmonary hypertension.

BACKGROUND: Some patients with chronic thromboembolic pulmonary hypertension (CTEPH) exhibit exercise intolerance due to reduced cardiac output (CO) even after successful balloon pulmonary angioplasty (BPA). Medical therapy is a potential option for such cases; however, it is unclear which patients necessitate it even after BPA. METHODS: This study included 286 patients with CTEPH who underwent BPA and right heart catheterization 1 year after the final BPA and classified them into no-medication and withdrawal groups. The no-medication group comprised patients without pulmonary hypertension (PH) medications before and after BPA, while the withdrawal group included patients who received PH medications before BPA and discontinued them after BPA. We assessed differences in the changes in CO after BPA from baseline (ΔCO) between the 2 groups. Additionally, we evaluated the ΔCO among different age categories within each group: younger (<60 years), middle-aged (60-70 years), and older adults (≥70 years). RESULTS: After adjusting baseline covariates, overall CO did not differ significantly. However, ΔCO was significantly positive in the no-medication group but negative in the withdrawal group (0.32 and -0.33, difference in ΔCO: -0.65, 95% confidence intervals: -0.90 to -0.40). A significantly positive effect on ΔCO was observed in younger and middle-aged individuals, with a significant interaction between age and ΔCO in no-medication groups. CONCLUSIONS: Increasing CO with BPA alone may be challenging with age in patients with CTEPH. Given that discontinuation of PH medication after BPA decreased CO more than the effect of BPA, medical therapy might be necessary even after successful BPA.

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

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

Low incidence of restenosis after successful balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension.

Balloon pulmonary angioplasty (BPA) is now a treatment option for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, the incidence of restenosis and long-term changes in vessel diameters in pulmonary arteries after BPA are unknown. The present study investigated the incidence of restenosis by measuring changes in vessel diameter after BPA. We reviewed 58 patients (168 lesions) with CTEPH who underwent single dilation for the target lesion (type A/B/C lesions) during BPA procedure followed by selective pulmonary angiography more than 6 months after the final BPA procedure. The outcomes of BPA were assessed in terms of pulmonary artery diameters. In a median follow-up of 1.9 (1.2-2.7) years, restenosis occurred in only one case with a type C lesion after BPA (0.6%). In type A/B lesions, the minimal lumen diameter was significantly enlarged at follow-up after BPA [3.48 (2.59-4.34) to 4.22 (3.31-4.90) mm]. In type C lesions, the minimal lumen diameter was unchanged at follow-up after BPA [3.15 (1.96-3.64) to 3.28 (2.38-4.61) mm]. The present results revealed that restenosis after BPA rarely occurs in type A/B/C lesions. Minimal lumen diameters for type A/B lesions continually increased and those for type C lesions did not decrease. Stent implantation in type A/B/C lesions would be unnecessary after BPA.

Combination of rescue balloon pulmonary angioplasty and riociguat therapy for chronic thromboembolic pulmonary hypertension with nonsustained polymorphic ventricular tachycardia: A case report.

We encountered a case of frequent nonsustained polymorphic ventricular tachycardia (NSPVT) due to hemodynamically unstable chronic thromboembolic pulmonary hypertension (CTEPH). A 78-year-old woman was taking anticoagulants for CTEPH. She had refused specific treatment for CTEPH, including pulmonary vasodilators, because she was then asymptomatic. She fell and sustained a femoral neck fracture, and she was referred to our hospital in anticipation of a surgical repair. Her condition on admission was complicated by respiratory failure, and electrocardiogram monitoring showed frequent NSPVT. A right heart catheterization revealed high mean pulmonary artery pressure with severely reduced cardiac output. Pulmonary angiography showed bilateral stenosis and multiple obstructions. Because NSPVT was attributed to low cardiac output syndrome caused by CTEPH, rescue balloon pulmonary angioplasty (BPA) was performed, and riociguat treatment was initiated. Afterward, the NSPVT resolved. This case suggests that the combination of rescue BPA with riociguat therapy might be an immediate and effective treatment for patients with inoperable CTEPH and severe hemodynamic instability.

Rescue balloon pulmonary angioplasty for refractory heart failure in chronic thromboembolic pulmonary hypertension complicated with takotsubo cardiomyopathy.

Balloon pulmonary angioplasty (BPA) seems promising for treating critically ill patients with chronic thromboembolic pulmonary hypertension (CTEPH) because of its less invasive and stepwise nature. However, there are only a few reports on rescue BPA. Herein, we present a case of CTEPH and takotsubo cardiomyopathy in an 82-year-old female. Despite treatment with catecholamines and intra-aortic balloon pumping, low output syndrome due to right heart failure with CTEPH and left heart failure with takotsubo cardiomyopathy did not improve. Therefore, rescue BPA for CTEPH was performed; this immediately improved the patient's hemodynamics. Learning objective: Rescue balloon pulmonary angioplasty (BPA) is an option for critically ill patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) that requires immediate improvement of hemodynamics. BPA strategy initially aimed at partial improvement of pulmonary circulation would be useful in treating CTEPH complicated by refractory right and left heart failure due to coexisting left-sided heart disease.

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.

Protocol for a multicentre, double-blind, randomised, placebo-controlled trial of riociguat on peak cardiac index during exercise in patients with chronic thromboembolic pulmonary hypertension after balloon pulmonary angioplasty (THERAPY-HYBRID-BPA trial).

OBJECTIVES: Balloon pulmonary angioplasty (BPA) and medical therapy, such as soluble guanylate cyclase stimulators, are recommended treatments for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are ineligible for pulmonary endarterectomy (PEA). However, monotherapy with BPA or medical therapy cannot always eliminate symptoms such as exertional dyspnoea. Thus, this study aims to clarify the efficacy of continuous treatment with riociguat in inoperable CTEPH patients with normalised haemodynamics after BPA. METHODS AND ANALYSIS: This is a double-blind, multicentre, randomised, placebo-controlled trial. Participants with CTEPH who are ineligible for PEA will receive riociguat followed by BPA. Subsequently, participants will be randomised (1:1) into either riociguat continuing or discontinuing groups and will be observed for 16 weeks after randomisation. The primary endpoint will be the change in peak cardiac index (CI) during the cardiopulmonary exercise test. In the primary analysis, the least square mean differences and 95% CIs for the change in peak CI at 16 weeks between the groups will be estimated by a linear mixed-effects model with baseline value as a covariate, treatment group as a fixed effect and study institution as a random effect. ETHICS AND DISSEMINATION: National Hospital Organisation Review Board for Clinical Trials (Nagoya) and each participating institution approved this study and its protocols. Written informed consent will be obtained from all participants. The results will be disseminated at medical conferences and in journal publications. REGISTRATION DETAILS: Japan Registry of Clinical Trials: jRCT no. 041200052. CLINICALTRIALS: gov by National Library of Medicine Registry ID: NCT04600492. TRIAL REGISTRATION NUMBER: NCT04600492.

Long-term outcome of chronic thromboembolic pulmonary hypertension using direct oral anticoagulants and warfarin: a Japanese prospective cohort study.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) requires lifelong anticoagulation. Long-term outcomes of CTEPH under current anticoagulants are unclear. OBJECTIVES: The CTEPH AC registry is a prospective, nationwide cohort study comparing the safety and effectiveness of direct oral anticoagulants (DOACs) and warfarin for CTEPH. PATIENTS/METHODS: Patients with CTEPH, both tre atment-naïve and on treatment, were eligible for the registry. Inclusion criteria were patients aged ≥20 years and those who were diagnosed with CTEPH according to standard guidelines. Exclusion criteria were not specified. The primary efficacy outcome was a composite morbidity, and mortality outcome comprised all-cause death, rescue reperfusion therapy, initiation of parenteral pulmonary vasodilators, and worsened 6-minute walk distance and WHO functional class. The safety outcome was clinically relevant bleeding, including major bleeding. RESULTS: Nine hundred twenty-seven patients on oral anticoagulants at baseline were analyzed: 481 (52%) used DOACs and 446 (48%) used warfarin. The 1-, 2-, and 3-year rates of composite morbidity and mortality outcome were comparable between the DOAC and warfarin groups (2.6%, 3.1%, and 4.2% vs 3.0%, 4.8%, and 5.9%, respectively; P = .52). The 1-, 2-, and 3-year rates of clinically relevant bleeding were significantly lower in DOACs than in the warfarin group (0.8%, 2.4%, and 2.4% vs 2.5%, 4.8%, and 6.4%, respectively; P = 0.036). Multivariable Cox proportional-hazards regression models revealed lower risk of clinically relevant bleeding in the DOAC group than the warfarin group (hazard ratio: 0.35; 95% CI: 0.13-0.91; P = .032). CONCLUSION: This registry demonstrated that under current standard of care, morbidity and mortality events were effectively prevented regardless of anticoagulants, while the clinically relevant bleeding rate was lower when using DOACs compared with warfarin.

Outcome of mean pulmonary arterial pressure-based intensive treatment for patients with pulmonary arterial hypertension.

BACKGROUND: Mean pulmonary arterial pressure (mPAP) has not been recognized as a therapeutic target for pulmonary arterial hypertension (PAH). However, previous reports demonstrated that the survival of patients with some types of pulmonary hypertension was associated with mPAP. Therefore, we treated all subsets of PAH patients with the aim of lowering mPAP and evaluated the efficacy of the treatment algorithm. METHOD: From September 2014 to August 2019, 43 consecutive patients with PAH on treatment <3 months on referral were enrolled in this study. They were treated according to our treatment algorithm mainly based on World Health Organization functional class, mPAP, and percent predicted diffusing capacity of the lung for carbon monoxide. The therapeutic goal was the achievement of mPAP <40 mmHg at follow-up. We evaluated clinical parameters, survival rate, and its determinants. Survival analyses were conducted using the Kaplan-Meier method and the relationship between all-cause death and selected variables was analyzed using the Cox proportional hazards model for mortality. RESULTS: mPAP significantly improved at the last follow-up [45 (35-55) mmHg to 24 (19-30) mmHg, p < 0.05], and the therapeutic goal was achieved in 37 patients (86%). The 5-year survival rate of all patients was 90.7%. The survival rate of patients who achieved the therapeutic goal (3- and 5-year survival: 97.3%) was significantly better than that of the patients who did not achieve the therapeutic goal (3-year survival: 50.0%, p < 0.05). The 5-year survival rates of the patients were the same among different treatment regimens (p = 0.985). mPAP <40 mmHg at follow-up was the independent predictor of survival. CONCLUSIONS: Lowering mPAP resulted in favorable outcomes in all subsets of PAH patients, making it a therapeutic goal.

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

Background: Treatment strategy for vascular injury during balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) was uncertain. Objectives: This study aimed to identify an optimal therapeutic strategy for vascular injury during BPA in patients with CTEPH. Methods: This study reviewed 207 patients with CTEPH and 956 BPA procedures between November 1, 2012 and November 30, 2015. Patients who were diagnosed with vascular injury during BPA, which was defined as angiographic signs or sudden respiratory and hemodynamic defects were included in this study. The study investigated the safety and efficacy of the hierarchically systematic treatment strategy including gelatin sponge embolization (GSE). Results: More than one-half of the 79 patients and 133 procedures with vascular injury were improved by general treatment with reversal of heparin and high-flow oxygen administration. The investigators performed conventional treatment of proximal vessel occlusion using a guiding or balloon catheter in 47 procedures (35%) in which the culprit vessels could be detected under patients' stable conditions. In 32 procedures (24%) without detected culprit lesions or improvement by conventional treatment, GSE could significantly improve patient condition. The treatment strategy obtained successful bailout in 98% of procedures with vascular injury. No patients who underwent GSE died within 30 days after the treatment. There was no significant difference in cumulative mortality rate (median follow-up: 6.6 years) between groups with or without GSE (15.6% vs 8.2%; adjusted HR: 1.47; 95% CI: 0.25-8.69; P = 0.67). Conclusions: Treatment strategy including GSE would be promising for vascular injury during BPA in patients with CTEPH.

Oxygen inhalation can selectively dilate pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension before balloon angioplasty.

BACKGROUND: Pulmonary injury is a major complication of balloon pulmonary angioplasty (BPA) for chronic thromboembolic pulmonary hypertension (CTEPH). Lung injury after BPA can be exacerbated by a high mean pulmonary arterial pressure (PAP). Although oxygen inhalation is expected to lower mean PAP in patients with CTEPH, no relevant investigation has been conducted. METHODS: Consecutive patients with CTEPH who underwent BPA were enrolled in this study. We evaluated the hemodynamics using right heart catheterization while breathing ambient air and with administration of 5 L/min oxygen for 10 min. RESULTS: This study included 52 consecutive patients with CTEPH, of whom 23 (44%) were treated with specific pulmonary vasodilators. Exposure to oxygen was well tolerated. Oxygen administration significantly decreased mean PAP by 3.8 ± 3.2 mmHg (p<0.001) and pulmonary vascular resistance by 0.8 ± 1.8 Wood units (p<0.001). Moreover, the ratio of pulmonary vascular resistance to systemic vascular resistance was significantly reduced by 13.5% (p<0.001). Multivariate regression analysis identified baseline mean PAP (ß = -0.427, p = 0.006) as the only significant predictor of decreased mean PAP under oxygen administration. No significant difference in oxygen effect on mean PAP was found between patients with and without vasodilators. CONCLUSIONS: In patients with CTEPH, 5 L/min supplemental oxygen inhalation could decrease mean PAP significantly by selective pulmonary artery dilatation, regardless of the usage of vasodilators, and thus could be helpful to maximize the safety of BPA. CLINICAL TRIAL REGISTRATION: UMIN Clinical Trials Registry (No.: UMIN000026882); URL: https://www.umin.ac.jp/ctr/index.htm.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension concomitant with Klippel-Trenaunay-Weber syndrome.

Klippel-Trenaunay-Weber syndrome (KTWS) is a rare congenital disorder characterized by cutaneous capillary malformations, bone hypertrophy, and multiple venous or lymphatic malformations. KTWS is associated with chronic thromboembolic pulmonary hypertension (CTEPH), presumably due to thromboembolism from multiple vascular malformations. Here, we report the first case series of patients with KTWS-CTEPH who underwent balloon pulmonary angioplasty (BPA). Both patients are alive 20 years and 1 year after the initial diagnosis of CTEPH, respectively, and are stable with improved hemodynamics. BPA may be an effective treatment option for patients with KTWS-CTEPH.

Pulmonary pressure recovery in idiopathic, hereditary and drug and toxin-induced pulmonary arterial hypertension: determinants and clinical impact.

BACKGROUND: Over the past two decades randomized controlled trials of combination treatments for Pulmonary Arterial Hypertension (PAH) have demonstrated improvements of clinical status but only modest reductions in mean pulmonary arterial pressure (mPAP). Recent experiences with upfront combination treatments including parenteral prostacyclins have shown more substantial mPAP reductions, and have provided grounds for reconsiderations of treatment. OBJECTIVES: To evaluate the possibility of achieving mPAP <25 mmHg with current treatments, its determinants and the prognostic impact of mPAP reduction. METHODS: 267 consecutive idiopathic, hereditary and drug and toxin-induced PAH patients treated with targeted therapies from three expert centers were followed with periodic clinical and hemodynamic assessments for survival detection. RESULTS: Fifty-four (20.2%) patients achieved a mPAP <25 mmHg over 58 months (IQR 27-90) of treatment. Determinants of mPAP <25 mmHg were mPAP at diagnosis (HR 0.96, 95C.I. 0.93-0.98, p = 0.002) and an upfront combination strategy (double oral combination: HR 2.3, 95C.I. 1.10-4.76, p = 0.02; one oral plus parenteral prostanoid: HR 3.6, 95C.I. 1.39-9.37, p = 0.008; triple combination employing parenteral prostanoids: HR 12.9, 95C.I. 4.9-33.2, p = 0.0001). Seventy-three patients (27.3%) died. Survival rates were 90%, 79%, 70%, 55%, and 42% at 1, 3, 5, 10, and 15 years, respectively. Mean PAP during follow-up, days from diagnosis to prostanoid initiation and prostanoid maximum dose emerged as independent predictors of survival (Uno-C-index: 0.85). A mPAP ≤35 mmHg during follow-up was identified as the best cutoff value for prediction of survival. CONCLUSIONS: Reduction to a mean PAP ≤ 35 mmHg appears to be a meaningful treatment target in idiopathic, hereditary and drug and toxin-induced pulmonary arterial hypertension.

Balloon pulmonary angioplasty versus riociguat in inoperable chronic thromboembolic pulmonary hypertension (MR BPA): an open-label, randomised controlled trial.

BACKGROUND: Treatment options for patients with chronic thromboembolic pulmonary hypertension ineligible for pulmonary endarterectomy (inoperable CTEPH) include balloon pulmonary angioplasty (BPA) and riociguat. However, these two treatment options have not been compared prospectively. We aimed to compare the safety and efficacy of BPA and riociguat in patients with inoperable CTEPH. METHODS: This open-label, randomised controlled trial was conducted at four high-volume CTEPH centres in Japan. Patients aged 20-80 years with inoperable CTEPH (mean pulmonary arterial pressure ≥25 to <60 mm Hg and pulmonary artery wedge pressure ≤15 mm Hg) and WHO functional class II or III were randomly assigned (1:1) to BPA or riociguat via a computer program located at the registration centre using a minimisation method with biased-coin assignment. In the BPA group, the aim was for BPA to be completed within 4 months of the initial date of the first procedure. BPA was repeated until mean pulmonary arterial pressure decreased to less than 25 mm Hg. The frequency of BPA procedures depended on the difficulty and number of the lesions. In the riociguat group, 1·0 mg riociguat was administered orally thrice daily. When the systolic blood pressure was maintained at 95 mm Hg or higher, the dose was increased by 0·5 mg every 2 weeks up to a maximum of 2·5 mg thrice daily; dose adjustment was completed within 4 months of the date of the first dose. The primary endpoint was change in mean pulmonary arterial pressure from baseline to 12 months, measured in the full analysis set (patients who were enrolled and randomly assigned to one of the study treatments, and had at least one assessment after randomisation). BPA-related complications and indices related to clinical worsening were recorded throughout the study period. Adverse events were recorded throughout the study period and evaluated in the safety analysis set (patients who were enrolled and randomely assigned to one of the study treatments, and had received part of or all the study treatments). This trial is registered in the Japan Registry of Clinical Trials (jRCT; jRCTs031180239) and is completed. FINDINGS: Between Jan 8, 2016, and Oct 31, 2019, 61 patients with inoperable CTEPH were enrolled and randomly assigned to BPA (n=32) or riociguat (n=29). Patients in the BPA group underwent an average of 4·7 (SD 1·6) BPA procedures. In the riociguat group, the mean maintenance dose was 7·0 (SD 1·0) mg/day at 12 months. At 12 months, mean pulmonary arterial pressure had improved by -16·3 (SE 1·6) mm Hg in the BPA group and -7·0 (1·5) mm Hg in the riociguat group (group difference -9·3 mm Hg [95% CI -12·7 to -5·9]; p<0·0001). A case of clinical worsening of pulmonary hypertension occurred in the riociguat group, whereas none occurred in the BPA group. The most common adverse event was haemosputum, haemoptysis, or pulmonary haemorrhage, affecting 14 patients (44%) in the BPA group and one (4%) in the riociguat group. In 147 BPA procedures done in 31 patients, BPA-related complications were observed in 17 procedures (12%) in eight patients (26%). INTERPRETATION: Compared with riociguat, BPA was associated with a greater improvement in mean pulmonary arterial pressure in patients with inoperable CTEPH at 12 months, although procedure-related complications were reported. These findings support BPA as a reasonable option for inoperable CTEPH in centres with experienced BPA operators, with attention to procedure-related complications. FUNDING: Bayer Yakuhin. TRANSLATION: For the Japanese translation of the abstract see Supplementary Materials section.

Continual Improvement in Pressure Gradient at the Lesion After Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: Lung injury is a serious complication of balloon pulmonary angioplasty (BPA) for chronic thromboembolic pulmonary hypertension (CTEPH). Selecting a smaller balloon might minimize the occurrence of lung injury; however, it could also increase the risk of restenosis. METHODS: We analyzed the first target lesions in the initial BPA procedure in 34 consecutive patients with CTEPH. We measured proximal pressure with a guiding catheter and distal pressure with a pressure wire. We retrospectively investigated pressure gradients at the lesions before and immediately after the initial dilation with a smaller balloon and before the second procedure. RESULTS: The proximal pressure decreased, and the distal pressure increased immediately after the initial balloon dilation. The pressure gradient at the lesion diminished significantly by the second procedure (from 26.4 ± 10.7 to 18.2 ± 9.9 mm Hg, P < 0.001) without serious complications. The residual pressure gradient had further diminished (to 9.8 ± 6.5 mm Hg, P = 0.02) until the second procedure. The reduction in pressure gradient at the lesion from immediately after the initial balloon dilation to the second procedure was positively correlated with both the baseline mean pulmonary arterial pressure (r2 = 0.23, P = 0.004) and residual pressure gradient immediately after the initial balloon dilation (r2 = 0.58, P < 0.001). CONCLUSIONS: The residual pressure gradient at the lesion diminished continually after dilation with a smaller balloon. This strategy could decrease pulmonary arterial pressure safely. It would be reasonable to dilate the lesions sequentially in 2 procedures.