田邉 信宏

The original version of this article unfortunately contained a mistake. In the “Results” section, the percentage of patients with inoperable or persistent/recurrent CTEPH included in the study was reported as 85%. This has been corrected to 68% with this erratum.

BACKGROUND: The 6-min walk test (6MWT) is commonly performed to assess functional status in patients with chronic thromboembolic pulmonary hypertension. However, changes in heart rate and oxygen saturation (SpO2 ) patterns during 6MWT in patients with chronic thromboembolic pulmonary hypertension remain unclear. METHODS: Thirty-one subjects with chronic thromboembolic pulmonary hypertension were retrospectively evaluated to examine the relationships between the change in heart rate (Δheart rate), heart rate acceleration time, slope of heart rate acceleration, heart rate recovery during the first minute after 6MWT (HRR1), change in SpO2 (ΔSpO2 ), SpO2 reduction time, and SpO2 recovery time during 6MWT, and the severity of pulmonary hemodynamics assessed by right heart catheterization and echocardiography. RESULTS: Subjects with severe chronic thromboembolic pulmonary hypertension had significantly longer heart rate acceleration time (144.9 ± 63.9 s vs 96.0 ± 42.5 s, P = .033), lower Δheart rate (47.4 ± 16.9 vs 61.8 ± 13.6 beats, P = .02), and lower HRR1 (13.3 ± 9.0 beats vs 27.1 ± 9.2 beats, P < .001) compared to subjects with mild chronic thromboembolic pulmonary hypertension. Subjects with severe chronic thromboembolic pulmonary hypertension also had significantly longer SpO2 reduction time (178.3 ± 70.3 s vs 134.3 ± 58.4 s, P = .03) and SpO2 recovery time (107.6 ± 35.3 s vs 69.8 ± 32.7 s, P = .004) than did subjects with mild chronic thromboembolic pulmonary hypertension. Multivariate linear regression analysis showed only mean pulmonary arterial pressure independently was associated with heart rate acceleration time and slope of heart rate acceleration. CONCLUSIONS: Heart rate and SpO2 change patterns during 6MWT are predominantly associated with pulmonary hemodynamics in subjects with chronic thromboembolic pulmonary hypertension. Evaluating heart rate and SpO2 change patterns during 6MWT may serve as a safe and convenient way to follow the change in pulmonary hemodynamics.

BACKGROUND: Several new treatments for chronic thromboembolic pulmonary hypertension (CTEPH) have appeared in recent years, which have led to changes in the treatment algorithm. Changes in survival rates and prognostic factors, however, have not been estimated so far.Methods and Results:Two hundred and eighty patients were diagnosed with CTEPH at Chiba University Hospital between June 1986 and June 2016. Survival rate was investigated by date of treatment initiation (group 1, 1986-1998; group 2, 1999-2008; group 3, 2009-2016). Survival rates were also evaluated by treatment strategy: balloon pulmonary angioplasty (BPA), pulmonary endarterectomy (PEA), and medical treatment. Group 3 had significantly better disease-specific survival than groups 1 and 2 (5-year survival: 91.9% vs. 67.1%, 77.0%, respectively). For the non-PEA (BPA+medication) strategy, group 3 had better disease-specific survival than groups 1 and 2 (5-year survival: 94.9% vs. 54.6%, 74.2%, respectively). The PEA strategy had significantly better survival than the medication strategy in groups 1 and 2, whereas no difference was observed between the BPA, PEA, and medication strategies in group 3. CONCLUSIONS: Survival in CTEPH in the recent era has significantly improved, especially in non-PEA patients. BPA and selective pulmonary vasodilators could improve survival in the non-PEA group. In the present study, no difference in survival was found between PEA and non-PEA.

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by obstruction of the pulmonary vasculature by residual organized thrombi. A morphological abnormality inside mediastinum of CTEPH patient is enlargement of pulmonary artery. This paper presents an automated assessment of aortic and main pulmonary arterial diameters for predicting CTEPH in low-dose CT lung screening. The distinctive feature of our method is to segment aorta and main pulmonary artery using both of prior probability and vascular direction which were estimated from mediastinal vascular region using principal curvatures of four-dimensional hyper surface. The method was applied to two datasets, 64 lowdose CT scans of lung cancer screening and 19 normal-dose CT scans of CTEPH patients through the training phase with 121 low-dose CT scans. This paper demonstrates effectiveness of our method for predicting CTEPH in low-dose CT screening.

Background: The trend of the initial treatment strategy for pulmonary arterial hypertension (PAH) has changed from monotherapies to upfront combination therapies. This study analyzed treatments and outcomes in Japanese patients with PAH, using data from the Japan PH Registry (JAPHR), which is the first organized multicenter registry for PAH in Japan. Methods and Results: We studied 189 consecutive patients (108 treatment-naïve and 81 background therapy patients) with PAH in 8 pulmonary hypertension (PH) centers enrolled from April 2008 to March 2013. We performed retrospective survival analyses and analyzed the association between upfront combination and hemodynamic improvement, adjusting for baseline NYHA classification status. Among the 189 patients, 1-, 2-, and 3-year survival rates were 97.0% (95% CI: 92.1–98.4), 92.6% (95% CI: 87.0–95.9), and 88.2% (95% CI: 81.3–92.7), respectively. In the treatment-naïve cohort, 33% of the patients received upfront combination therapy. In this cohort, 1-, 2-, and 3-year survival rates were 97.6% (95% CI: 90.6–99.4), 97.6% (95% CI: 90.6–99.4), and 95.7% (95% CI: 86.9–98.6), respectively. Patients on upfront combination therapy were 5.27-fold more likely to show hemodynamic improvement at the first follow-up compared with monotherapy (95% CI: 2.68–10.36). Conclusions: According to JAPHR data, initial upfront combination therapy is associated with improvement in hemodynamic status.

BACKGROUND: Everolimus (ERL), a mammalian target of rapamycin (mTOR) inhibitor, has been used for the management of several advanced cancers. ERL frequently causes lung injury, although the clinical and radiographic features have not been clarified. The aim of this study was to assess the clinical features of ERL-induced lung injury and determine the associated risk factors. METHODS: This single-center, retrospective study included 45 patients (29 men, 16 women; age, 12-78 years) who had received ERL at our hospital between August 2010 and March 2016. Drug-induced lung injury (DILI) was diagnosed using the Japanese Respiratory Society criteria. We obtained information regarding the clinical course, symptoms, clinical findings, blood test findings, and chest computed tomography findings from the patients' medical records. Risk factors for DILI onset were investigated using the Wilcoxon rank sum test. RESULTS: Fifteen patients (33%) were diagnosed with DILI. The median time from ERL administration to DILI onset was 64 days. High Serum Krebs von den Lungen-6 (KL-6) levels and a low estimated glomerular filtration rate (eGFR) before ERL administration were found to be significant risk factors for DILI. KL-6 and lactate dehydrogenase (LDH) were significantly elevated at the onset of DILI. All 15 patients recovered; 11 were without steroids. CONCLUSIONS: Our results suggest that patients with high KL-6 levels and a low eGFR at baseline are at increased risk of ERL-induced lung injury. In addition, KL-6 and LDH may be useful biomarkers of ERL-induced lung injury.

Partial anomalous pulmonary venous return (PAPVR) is a rare congenital cardiovascular anomaly. A 68-year-old woman was referred to our hospital for detailed examination for pulmonary hypertension (PH). She had been diagnosed as having pulmonary artery dilation and suspected to have PH during a health check seven years prior. A contrast computed tomography showed that the right upper pulmonary vein (RUPV) returned to the superior vena cava (SVC) with a preserved normal connection to the left atrium (LA). Surgical repair was performed. We reported an extremely rare case of isolated PAPVR with PH showing dual drainage into the SVC and LA.

Background Balloon pulmonary angioplasty (BPA) is an alternative therapy for patients with chronic thromboembolic pulmonary hypertension who are ineligible for pulmonary endarterectomythe standard therapy. Currently, most reported results of BPA are from relatively small cohorts treated at single centers. The present study evaluated the safety and efficacy of BPA for chronic thromboembolic pulmonary hypertension based on a multicenter registry. Methods and Results A total of 308 patients (62 men and 246 women; mean age, 61 years) underwent 1408 procedures at 7 institutions in Japan. Data were retrospectively reviewed to evaluate clinical outcome and complications. Hemodynamics were significantly improved in 249 patients in whom BPA was terminated, most often because of improvement in mean pulmonary arterial pressure or symptomatic improvement after 1154 procedures. In 196 patients who underwent follow-up right heart catheterization, improvement of hemodynamic parameters was maintained. Mean pulmonary arterial pressure decreased from 43.211.0 to 24.3 +/- 6.4 mm Hg after final BPA and 22.5 +/- 5.4 mm Hg at follow-up, with significant reduction of concomitant use of pulmonary hypertension-targeted therapy and oxygen supplementation. Complications occurred in 511 (36.3%), including pulmonary injury (17.8%), hemoptysis (14.0%), and pulmonary artery perforation (2.9%). Twelve patients (3.9%) died during follow-up, including 8 patients who died within 30 days after BPA. The leading causes of death were right heart failure, multiorgan failure, and sepsis. Overall survival was 96.8% (95% confidence interval, 93.7%-98.4%) at 1 and 2 years and 94.5% (95% confidence interval, 89.3%-97.3%) at 3 years, respectively, after the initial BPA procedure for all 308 patients. Conclusions This multicenter registry suggested improved hemodynamic results after BPA. Complication rates were high, but overall survival was comparable with pulmonary endarterectomy. BPA may be an important therapeutic option in patients with chronic thromboembolic pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is characterized by progressive obstructive remodeling of pulmonary arteries. However, no reports have described the causative role of the autophagic pathway in pulmonary vascular endothelial cell (EC) alterations associated with PAH. This study investigated the time-dependent role of the autophagic pathway in pulmonary vascular ECs and pulmonary vascular EC kinesis in a severe PAH rat model (Sugen/hypoxia rat) and evaluated whether timely induction of the autophagic pathway by rapamycin improves PAH. Hemodynamic and histological examinations as well as flow cytometry of pulmonary vascular EC-related autophagic pathways and pulmonary vascular EC kinetics in lung cell suspensions were performed. The time-dependent and therapeutic effects of rapamycin on the autophagic pathway were also assessed. Sugen/hypoxia rats treated with the vascular endothelial growth factor receptor blocker SU5416 showed increased right ventricular systolic pressure (RVSP) and numbers of obstructive vessels due to increased pulmonary vascular remodeling. The expression of the autophagic marker LC3 in ECs also changed in a time-dependent manner, in parallel with proliferation and apoptotic markers as assessed by flow cytometry. These results suggest the presence of cross talk between pulmonary vascular remodeling and the autophagic pathway, especially in small vascular lesions. Moreover, treatment of Sugen/hypoxia rats with rapamycin after SU5416 injection activated the autophagic pathway and improved the balance between cell proliferation and apoptosis in pulmonary vascular ECs to reduce RVSP and pulmonary vascular remodeling. These results suggested that the autophagic pathway can suppress PAH progression and that rapamycin- dependent activation of the autophagic pathway could ameliorate PAH.

Background: Selexipag is an orally available prostacyclin receptor (IP receptor) agonist with a non-prostanoid structure. In this open-label Phase II trial, the efficacy and safety of selexipag in Japanese patients with pulmonary arterial hypertension (PAH) is examined. Methods and Results: Selexipag was administered at 200 ae g twice daily and titrated up to 1,600 ae g by increments of 200 ae g in 37 subjects to reach the individual maximum tolerated dose. At 16 weeks, in 33 patients comprising the per-protocol set, the pulmonary vascular resistance (PVR; primary endpoint) decreased from 683.2 +/- 237.3 to 560.3 +/- 238.7 dyn.s/cm(5) (P&lt;0.0001). For the secondary endpoint, the 6-min walk distance (6MWD) increased from 445.0 +/- 102.2 to 459.1 +/- 112.8 m (P= 0.0324); World Health Organization functional class improved in 4 patients (12.1%), and was maintained in 29 patients (87.9%). A decrease in PVR was also shown in patients treated with selexipag, on top of a phosphodiesterase inhibitor and endothelin receptor antagonist. Most of the commonly reported adverse events were consistent with those reported for other PGI(2) formulations. Thirty-four patients attained the individual maximum tolerated dose (maintenance dose). Conclusions: The efficacy and tolerability of selexipag in Japanese PAH patients was confirmed by improvement in pulmonary hemodynamics, exercise capacity, symptoms. Selexipag is an efficacious treatment option for Japanese PAH patients. (Trial registration: JAPIC Clinical Trials Information

BACKGROUND: Dilatation of the pulmonary artery and right ventricle on chest computed tomography images is often observed in patients with pulmonary hypertension. The clinical significance of these image findings has not been defined in chronic thromboembolic pulmonary hypertension. We investigated whether the pulmonary arterial and right ventricle dilatation was associated with poor outcome in chronic thromboembolic pulmonary hypertension. METHODS: This was a retrospective cohort investigation in 60 subjects with inoperable chronic thromboembolic pulmonary hypertension diagnosed consecutively between 1997 and 2010 at Chiba University Hospital. Digital scout multi-detector chest computed tomography images were obtained. The main pulmonary arterial to ascending aortic diameter ratio and the right ventricular to left ventricular diameter ratio were calculated. RESULTS: Main pulmonary arterial to ascending aortic diameter ratio ranged from 0.85 to 1.84, and right ventricular to left ventricular diameter ratio ranged from 0.71 to 2.88. During the observation period of 1284.5days (range, 21-4550days), 13 patients required hospitalization due to worsening; 6 of them died. Kaplan-Meier analysis showed significant differences in hospitalization between the patients with main pulmonary arterial to ascending aortic diameter ratio of ≥1.1 and <1.1 (log-rank test, p=0.014) and between the patients with right ventricular to left ventricular diameter ratio of ≥1.2 and <1.2 (log-rank test, p=0.013). There was a significant difference in the prognosis between the patients with RV/LV ratio≥1.2 and those with RV/LV ratio<1.2 (log-rank test, p=0.033). CONCLUSIONS: Main pulmonary arterial to ascending aortic diameter ratio measured using enhanced CT images was associated with the risk for first clinical exacerbation, and right ventricular to left ventricular diameter ratio was associated with the risk for poor prognosis in inoperable chronic thromboembolic pulmonary hypertension.

Pulmonary arteriovenous malformation (PAVM) is an abnormal blood vessel connecting a pulmonary artery and a vein, and is accompanied by paradoxical embolism to other organs due to a right-to-left shunt. We report the case of a 66-year-old woman with PAVM complicated by splenic infarction and abscess. Although the PAVM had been detected on a chest image 2 years previously, and she had been advised to have further investigations, she decided not to follow this further at the time. She then visited our hospital complaining of worsening dyspnoea on exertion. Detailed examinations revealed splenic infarction and abscessation due to PAVM. PAVM embolization was performed after antibiotic treatment. It is very rare for PAVM to be complicated by splenic infarction and abscess. Regardless of its size, embolization of a PAVM as soon as possible can reduce not only the risk of central nervous system complications, but also the risk of splenic infarction and abscess.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is difficult to diagnose as patients rarely present with specific symptoms. However, a mosaic attenuation pattern (MAP) in chest computed tomography (CT) suggests CTEPH. Areas of increased attenuation are not always visible using default CT settings for the lung. Thus, we examined the utility of non-contrast CT imaging with new settings focusing on MAP (CTMosaic) for the assessment of pulmonary perfusion in patients with CTEPH. The regional perfusion defects visualized using CTMosaic and single-photon-emission CT with fusion of CT images (SPECT/CT) were compared. METHODS: Twenty-seven patients with CTEPH (20 women; aged 62.8±7.9 years) underwent imaging with non-contrast CT and SPECT/CT. We converted non-contrast mediastinal CT images into various CT window settings to identify the MAP, and the CT window setting that could most easily identify the MAP was defined as CTMosaic. We then scored and compared lung segments depending on the degree of perfusion on CTMosaic and SPECT/CT. RESULTS: CTMosaic was identified as the CT window setting in which the window level was -800 Hounsfield units (HU), and the window width was 200 HU. Using CTMosaic, MAP was detected in 366 of 486 segments (75.3%). The agreement between CTMosaic and perfusion defects on SPECT/CT was 84.9%. Weighted kappa statistics demonstrated a good agreement between the two examinations (κ=0.605, 95% confidence interval, 0.502-0.707). CONCLUSIONS: The CTMosaic setting can easily identify an MAP in CTEPH patients. Therefore, this may be useful as a simple and cost-effective evaluation method for blood distribution in patients with CTEPH.

Pulmonary arterial hypertension (PAH) is a lethal disease that often affects the young. Although Bone Morphogenetic Protein Receptor Type 2 gene (BMPR2) mutations are related with idiopathic and heritable PAH, the low penetrance and variable expressivity in PAH suggest the existence of other genetic and/or environmental factors. In this study, we aimed to identify novel genetic factors associated with PAH, irrespective of BMPR2 mutation. We performed genome-wide association study (GWAS) in a Japanese population comprising 44 individuals with idiopathic and heritable PAH, and 2,993 controls. Seven loci identified in the genome-wide study were submitted to the validation study, and a novel susceptibility locus, PDE1A|DNAJC10, was identified that maps to 2q32.1 (rs71427857, P = 7.9 x 10(-9), odds ratio in the validation study = 5.18; 95% CI 1.86 - 14.42). We also found the augmentation of PDE1A protein in distal remodeled pulmonary artery walls in idiopathic PAH patients. Given that phosphodiesterase 5 inhibitors are effective for the treatment of idiopathic and heritable PAH, our findings suggest that PDE1A could be a novel therapeutic target of PAH.

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) require lifelong anticoagulation therapy. However, the bleeding risk and recurrence of venous thromboembolism (VTE) in CTEPH patients who are administered warfarin have not been adequately evaluated. The purpose of this study was to evaluate the risk of clinically relevant bleeding, recurrent VTE, and clinical worsening in patients with CTEPH who were administered warfarin. The clinical records of 72 patients with CTEPH who regularly visited our institution and were administered warfarin were retrospectively reviewed between 1 January 2011 and 31 December 2015. We investigated the incidence of clinically relevant bleeding events, recurrent VTE, and hospitalization for the deterioration of pulmonary hypertension or right heart failure (RHF) during the observation period. The mean observation period for the 72 patients was 3.601.60 person-years. Clinically relevant bleeding, RHF, and recurrent VTE occurred in 21 (29.2%), eight (11.1%), and three (4.2%) of 72 patients, respectively, and the incidence rates for these events were 8.1%/person-year, 3.1%/person-year, and 1.2%/person-year, respectively. The incidence rates for the major and non-major bleeding events were 5.0%/person-year and 3.9%/person-year, respectively. The incidence of clinically relevant bleeding events was 20.8%/person-year during medical treatment with a soluble guanylate cyclase stimulator. One of 35 patients (2.9%) during the post-pulmonary endarterectomy period experienced hemoptysis during observation period (&gt; 6 months after pulmonary endarterectomy). No bleeding events occurred during the post-balloon pulmonary angioplasty period. In conclusion, warfarin effectively prevents VTE recurrence in CTEPH patients, but its effects may be associated with a considerable bleeding risk.

BACKGROUND: Riociguat, the first approved drug for patients with chronic thromboembolic pulmonary hypertension (CTEPH), is a soluble guanylate cyclase (sGC) Stimulator. It directly stimulates sGC independently of nitric oxide (NO) and increases sGC sensitivity for NO. The safety and efficacy of transitioning from a phosphodiesterase 5 inhibitor (PDE5i) to riociguat is unknown. METHODS AND RESULTS: Twenty-three patients were prospectively enrolled: 8 symptomatic patients with inadequate clinical responses to PDE5i were changed to riociguat (transitioned group); 15 started riociguat anew (new or add-on group). We analyzed the change from baseline to 6-12 months of riociguat treatment for the 6-minute walk distance (6MWD), mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI), partial pressure of oxygen in arterial blood (PaO2), brain natriuretic peptide (BNP), World Health Organization (WHO) functional class, safety and adverse events. The mPAP, BNP and WHO functional class significantly improved in total. In the transitioned group, BNP significantly decreased by -116.5±188.6pg/ml (P=0.0156). The 6MWD, mPAP, PVR, CI, and PaO2 improved but not significantly. The baseline condition was significantly more severe in the transitioned than in the new or add-on group. No patients discontinued riociguat. Relatively rapid transitioning from PDE5i to riociguat was safe under careful observation. CONCLUSIONS: Transitioning to riociguat may be safe and effective in CTEPH patients with inadequate clinical responses to PDE5i.

Purpose: Right ventricular myocardial (RVM) fibrosis may be a significant indicator of prognosis in pulmonary hypertension (PH). To detect the presence of RVM fibrosis in PH subjects, we employed ECG gated 320-slice CT. Methods: 62 confirmed PH subjects (16 males; 55 +/- 16 years; 45 chronic thromboembolic PH (CTEPH) who underwent conventional non-surgical medical therapy; and 17 pulmonary arterial hypertension (PAH)) underwent ECG-gated 320-slice CT. On CT, RV fibrosis was defined as contrast defect in the early phase and conversely abnormal enhancement in the late phase. Results: RVM fibrosis was observed in 14 subjects (23%) on CT (CTEPH 22%; PAH 29%; P = 0.91). CT attenuation of RVM in the late phasewas significantly greater in subjectswith RVM fibrosis than in thosewithout (P= 0.025). ROC curves of CT attenuation of RVM in the early and late phase, and ratio of CT attenuation of RVM in the early phase/late phase showed AUCs of 0.55, 0.70, and 0.65, respectively. The best cutoff points of 79.5 HU (sensitivity of 50% and specificity of 69% for CT attenuation of RVM in the early phase, P= 0.59), 99.5 HU (sensitivity of 50% and specificity of 88% for CT attenuation of RVM in the late phase, P = 0.025), and 1.416 (sensitivity of 29% and specificity of 94% for ratio of CT attenuation of RVM in the early phase/late phase, P = 0.092) were used to distinguish subjects +/- RVM fibrosis. Conclusion: Quantitative-measurement of CT attenuation of RVMin the late phasemay be able to detect presence of RVM fibrosis in PH subjects. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

Background and objectiveChronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease in some patients, despite improved treatments. Microvasculopathy has been implicated in the poor outcomes of patients with CTEPH. A reduction in the diffusing capacity for carbon monoxide (DLCO ) was previously suggested to indicate microvasculopathy in CTEPH patients; therefore, we assessed DLCO /alveolar ventilation (DLCO /V-A ) as a prognostic and pathophysiological marker in CTEPH. MethodsWe performed a retrospective cohort study of 214 CTEPH patients consecutively diagnosed between 1986 and 2011. After exclusion of 24 patients because of missing DLCO data or severe obstructive impairment, the mortality rates of medically treated patients classified with normal or decreased DLCO values were compared, and prognostic factors were determined. The relationship between long-term surgical outcomes and DLCO /V-A was also investigated. ResultsNinety-one inoperable patients were treated medically, two of whom underwent balloon pulmonary angioplasty. Ninety-nine underwent pulmonary endarterectomy. The 5-year survival rate of medically treated patients was significantly lower in patients with decreased DLCO /V-A than in those with normal values (61.4% vs 90.4%, P=0.017). Decreased preoperative DLCO /V-A was associated with a smaller percent decrease in post-operative pulmonary vascular resistance, but not with the extent of proximal thrombi; these results may support our hypothesis that DLCO reflects microvascular involvement. ConclusionDecreased DLCO/V-A was associated with poor outcomes of medically treated CTEPH patients; and may be useful for identifying high-risk patients, potentially leading to earlier and more appropriate interventions. This is the first study identifying decreased diffusing capacity for carbon monoxide (DLCO)/alveolar ventilation (V-A) (&lt;80%) as an independent poor prognostic factor in medically treated chronic thromboembolic pulmonary hypertension (CTEPH) patients. This study also demonstrated that DLCO/V-A may reflect peripheral microvasculopathy, which is a major cause of poor outcome.

A 30-year-old Japanese man was diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) with lupus anticoagulants (LAs) in 2003. He underwent pulmonary endarterectomy after the placement of an inferior vena cava filter (IVCF) in 2004, and treatment with warfarin was continued. In 2014, IVCF occlusion and marked collateral circulation were noted during an examination for transient dyspnea; however, his warfarin level was within the therapeutic range for 88.9% of the time from 2003 to 2014. We herein report a rare case of CTEPH and LAs with IVCF occlusion; in such cases, intense treatment may be required.

Background-Balloon pulmonary angioplasty (BPA) is an alternative therapy for patients with chronic thromboembolic pulmonary hypertension who are ineligible for pulmonary endarterectomy-the standard therapy. Currently, most reported results of BPA are from relatively small cohorts treated at single centers. The present study evaluated the safety and efficacy of BPA for chronic thromboembolic pulmonary hypertension based on a multicenter registry. Methods and Results-A total of 308 patients (62 men and 246 women mean age, 61 years) underwent 1408 procedures at 7 institutions in Japan. Data were retrospectively reviewed to evaluate clinical outcome and complications. Hemodynamics were significantly improved in 249 patients in whom BPA was terminated, most often because of improvement in mean pulmonary arterial pressure or symptomatic improvement after 1154 procedures. In 196 patients who underwent followup right heart catheterization, improvement of hemodynamic parameters was maintained. Mean pulmonary arterial pressure decreased from 43.2±11.0 to 24.3±6.4 mm Hg after final BPA and 22.5±5.4 mm Hg at follow-up, with significant reduction of concomitant use of pulmonary hypertension-targeted therapy and oxygen supplementation. Complications occurred in 511 (36.3%), including pulmonary injury (17.8%), hemoptysis (14.0%), and pulmonary artery perforation (2.9%). Twelve patients (3.9%) died during follow-up, including 8 patients who died within 30 days after BPA. The leading causes of death were right heart failure, multiorgan failure, and sepsis. Overall survival was 96.8% (95% confidence interval, 93.7%-98.4%) at 1 and 2 years and 94.5% (95% confidence interval, 89.3%-97.3%) at 3 years, respectively, after the initial BPA procedure for all 308 patients. Conclusions-This multicenter registry suggested improved hemodynamic results after BPA. Complication rates were high, but overall survival was comparable with pulmonary endarterectomy. BPA may be an important therapeutic option in patients with chronic thromboembolic pulmonary hypertension.

Rationale: Pulmonary arterial hypertension (PAH) is characterized by obstructive lesions and vasoconstriction of the pulmonary arteries. Early therapeutic interventions with vasodilator drugs are thought to be beneficial in PAH. However, it remains unknown whether the severity of intimal obstruction is associated with increased pulmonary arterial pressure and whether reduction of vasoconstriction in the earlier stage by these drugs has a beneficial effect. Therefore, the aims of this study were to investigate these issues in a rat model of severe PAH. Methods: A rat model of severe PAH was created by injection of a vascular endothelial growth factor receptor blocker in combination with hypoxia for the first 3 weeks followed by normoxia for the next 9 weeks. To assess intimal obstruction, "the pulmonary artery occlusion index (PAOI)" was developed to digitize all lesions. The small pulmonary arteries were assessed by this index, and the association between right ventricular systolic pressure (RVSP) and PAOI was investigated. An endothelin receptor antagonist, ambrisentan, was administered by gavage to rats during either hypoxia (Prevention study group, n=25) or normoxia (Early treatment group, n=15). Results: PAOI showed a positive correlation with RVSP, and both RVSP and PAOI increased gradually over time. There were no severe occlusive lesions in either group, but the density of partially occlusive lesions was significantly decreased in the Prevention study group. Conclusion: A novel PAOI index was developed, and this index was strongly correlated with RVSP. Furthermore, ambrisentan reduced luminal occlusive lesions more effectively when treatment was given during the first 2 weeks of hypoxia.

Background/objectives: Several studies have already shown the correlation between the right ventricle (RV) hemodynamic values and either glucose uptake or fatty acid uptake in the RV, respectively. However, there are few studies to compare the RV metabolic alteration before and after treatment for pulmonary hypertension. The aims of this study are to assess right ventricular glucose and fatty acid in chronic thromboembolic pulmonary hypertension (CTEPH) patients before and after pulmonary thromboendarterectomy and to examine whether there is a correlation between right ventricular glucose and fatty acid uptake. Methods: To assess glucose and fatty acid accumulation in the RV, [F-18] fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) and I-123-beta-methyl iodophenyl pentadecanoic acid (BMIPP) imaging were performed in CTEPH patients before (FDG: n = 20, BMIPP: n = 13) and after (FDG: n = 12, BMIPP: n = 8) thromboendarterectomy. Results: Both [F-18] FDG uptake and I-123-BMIPP uptake in RV of post-PEA patients obviously decreased after this operation procedure (p &lt; 0.01). The right ventricle [F-18] FDG uptake was also significantly correlated with I-123-BMIPP uptake (r = 0.45, p = 0.04). Conclusions: In this study, we observed that both glucose and fatty acid accumulated in the RV of patients with CTEPH. Although the exact details of the altered energy metabolism in the stressed RV remain unknown, this is the first study to evaluate both glucose and fatty acid uptake before and after thromboendarterectomy in patients with CTEPH, even though the number of the patient is limited. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

Background Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by occlusion of pulmonary arteries by organized chronic thrombi. Persistent hypoxemia and residual pulmonary hypertension (PH) following successful pulmonary endarterectomy (PEA) are clinically important problems; however, the underlying mechanisms remain unclear. We have previously reported that residual PH is closely related to severe pulmonary vascular remodeling and hypothesize that this arteriopathy might also be involved in impaired gas exchange. The purpose of this study was to evaluate the association between hypoxemia and pulmonary arteriopathy after PEA. Methods and Results Between December 2011 and November 2014, 23 CTEPH patients underwent PEA and lung biopsy. The extent of pulmonary arteriopathy was quantified pathologically in lung biopsy specimens. We then analyzed the relationship between the severity of pulmonary arteriopathy and gas exchange after PEA. We observed that the severity of pulmonary arteriopathy was negatively correlated with postoperative and follow-up PaO2 (postoperative PaO2: r = -0.73, p = 0.0004; follow-up PaO2: r = -0.66, p = 0.001), but not with preoperative PaO2 (r = -0.373, p = 0.08). Multivariate analysis revealed that the obstruction ratio and patient age were determinants of PaO2 one month after PEA (R-2 = 0.651, p = 0.00009). Furthermore, the obstruction ratio and improvement of pulmonary vascular resistance were determinants of PaO2 at follow-up (R-2 = 0.545, p = 0.0002). Severe pulmonary arteriopathy might increase the alveolar-arterial oxygen difference and impair diffusion capacity, resulting in hypoxemia following PEA. Conclusion The severity of pulmonary arteriopathy was closely associated with postoperative and follow-up hypoxemia.

Sporadic and familial elastin mutations can occur in large vessel stenosis such as supravalvular aortic stenosis and narrowing of the descending aorta. However, there are very few reports regarding the arteriopathy of cerebral, pulmonary or abdominal arteries in elastin mutations. We herein report the case of a Japanese female patient presenting with multiple arteriopathy including moyamoya disease, a tortuosity of abdominal arteries and pulmonary hypertension due to peripheral pulmonary artery stenosis. This case suggests the possible progression of cerebral arteriopathy including moyamoya disease in patients with elastin mutations. © 2016 Wiley Periodicals, Inc.

Background: Macitentan is a novel, dual endothelin receptor antagonist with sustained receptor binding, used for the long-term treatment of pulmonary arterial hypertension (PAH). In the present study, we assessed the efficacy and safety of macitentan in Japanese patients with PAH. Methods and Results: Macitentan was administered at a once-daily dose of 10 mg in 30 patients. The primary endpoint was change in pulmonary vascular resistance (PVR) from baseline to week 24. Change to week 24 in the other hemodynamic parameters, 6-min walk distance (6MWD), World Health Organization (WHO) functional class, and plasma N-terminal pro-brain natriuretic peptide (NT-pro-BNP), as well as time to clinical deterioration up to week 52 were also assessed as secondary endpoints. In the 28 patients on per-protocol analysis, PVR decreased from 667 +/- 293 to 417 +/- 214 dyn.sec.cm(-5) (P&lt;0.0001). 6MWD increased from 427 +/- 128 to 494 +/- 116m (P&lt;0.0001). WHO functional class improved in 13 patients (46.4%) and was maintained in 15 patients (53.6%), and NT-pro-BNP was reduced by 18% (P&lt;0.0001). The favorable treatment effect on PVR was apparent regardless of concomitant therapy for PAH. Conclusions: Macitentan was efficacious and well tolerated and improved the hemodynamic parameters, exercise capacity, symptoms, and clinical biomarkers in Japanese PAH patients. Macitentan can be a valuable therapeutic option for Japanese patients with PAH. (Trial registration: JAPIC Clinical Trials Information [JapicCTl-121986].)

BACKGROUND: Mean pulmonary arterial pressure (MPAP) is an important pulmonary hemodynamic parameter used in the management of patients with chronic thromboembolic pulmonary hypertension (CTEPH). We compared echocardiography-derived estimates of MPAP with right heart catheterization (RHC) to identify reliable noninvasive methods of estimating MPAP-derived RHC (MPAPRHC) in these patients. METHODS AND RESULTS: Echocardiography and RHC were performed in 56 patients with CTEPH (60.5±12.0 years; 44 females). We measured the tricuspid regurgitation (TR) pressure gradient (TRPG) using echocardiography. The mean systolic right ventricular (RV)-right atrial (RA) gradient was calculated by tracing the TR time velocity flow. Systolic and mean pulmonary artery pressures (SPAPTRand MPAPTR) estimated from TRPG and mean systolic RV-RA gradient were calculated by adding RA pressure based on the inferior vena cava. MPAPChemlawas calculated using Chemla's formula: 0.61×SPAPTR+2 mmHg. MPAPRHCand pulmonary vascular resistance were 35.9±11.3 mmHg and 6.6±3.6 Wood units, respectively. The mean difference from MPAPRHCand limits of agreement were -1.5 mmHg and -19.6 to 16.5 mmHg for MPAPTR, and -4.6 mmHg and -24.5 to 15.2 mmHg for MPAPChemla. Accuracy within 10 mmHg and 5 mmHg of MPAPRHCwas 80.4% and 46.4% for MPAPTR, and 71.4% and 48.2% for MPAPChemla, respectively. CONCLUSIONS: MPAPTRand MPAPChemlaare reliable estimates for MPAPRHCin patients with CTEPH. (Circ J 2016; 80: 1259-1264).

Background: The postoperative changes in the coagulation-fibrinolysis system and the association between the system and postoperative course of patients with chronic thromboembolic pulmonary hypertension (CTEPH) who have undergone pulmonary endarterectomy (PEA) remain unclear. Methods and Results: Between 1986 and 2013, 117 patients (55.1+/-11.2 years, preoperative mean pulmonary arterial pressure 46.5+/-10.5 mmHg) underwent PEA, and 15 patients died during the perioperative period. We studied the association between the preoperative coagulation-fibrinolysis markers and surgical outcomes of all patients, and the long-term outcomes of the 102 survivors from the date of PEA. We also investigated the postoperative changes in coagulation-fibrinolysis markers and their association with residual pulmonary hypertension (PH) in 20 consecutive patients. Only an elevated factor VIII level was associated with perioperative death. Thrombomodulin and plasminogen values were significantly increased after PEA. Univariate logistic regression analysis revealed that D-dimer positivity at follow-up was a risk factor for residual PH. Patients with both an elevated fibrinogen level (&gt;= 291 mg/dl [median]) and decreased plasminogen activity (&lt;100% [median]) had significantly worse disease-specific survival than the other patients (5-year disease-specific survival: 84.0% vs. 100%, respectively; P=0.0041 [log-rank test]). Conclusions: Preoperatively high fibrinogen and low plasminogen values in patients with CTEPH are associated with poor long-term postoperative outcome. PEA benefited not only the pulmonary hemodynamics but also the coagulation-fibrinolysis system of patients.

喀血患者における320列CTを用いたダイナミックスタディ(4Dスタディ)での体循環動脈について検討した。320列CTを用いた4Dスタディを行い、その後に血管造影検査・塞栓術を施行した9例(男性3名、女性6名、32〜83歳)を対象とした。いずれも喀血部位と血管造影検査で同定したシャント部位は一致した。シャントの体循環側の責任血管は気管支動脈8例、胸壁の動脈1例であった。肺血管は全て肺動脈で、全例で止血が得られた。4D画像では、全例で喀血の原因となっているシャント血流を確認した。7例において2D画像上で関心領域を設定でき、CT値の測定とそのダイナミックカーブの作成を行った。2例は背景肺のコンソリデーションの内部にシャント部位があり、肺血管の形態が認識できず、関心領域を設定できなかった。シャント部位のCT値のダイナミックカーブは二峰性の上昇を呈し、一つめのピークは肺動脈幹よりも低いCT値、二つめのピークは高いCT値を呈した。

Background: Partial anomalous pulmonary venous return (PAPVR) is characterized by an abnormal connection of the pulmonary vein (PV). The left-to-right shunt results in an increased pulmonary blood flow, which may be followed by developing pulmonary hypertension (PH). We found that computed tomography (CT) scans may be misinterpreted, potentially leaving anomalous PVs undetected when reviewing diagnostic findings of PAPVR patients. The purpose of this study was to delineate this risk and assess the usefulness of our interpretation methods. Methods: We retrospectively reviewed the records of 8 patients diagnosed with PAPVR, diagnosed with right heart catheterization (RHC) findings, at our department between 1991 and 2013. Our CT screening method for assessing anomalous PVs consisted of two points: 1) confirming that four PVs were connected to the left atrium (LA) and 2) checking that the vena cava was not connected with anomalous PVs. The accuracy of this method was analyzed in a blinded manner. Results: In 4 patients, anomalous PVs delineated on enhanced CT scan images obtained before RHC were undetected. The sensitivity and specificity of detecting PAPVRs using our protocol were 0.800 and 0.978, respectively. Four of 8 patients went on to develop PH. Age at the time of diagnosis was positively correlated with mean pulmonary arterial pressure (r=0.929, p=0.002). Conclusion: There is a potential risk of CT scan misinterpretation when looking for anomalous PVs. Careful interpretation of CT findings that focus on PVs may be useful for detecting PAPVR and obtaining a PH differential diagnosis.

BACKGROUND: The insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme gene (ACE) and the C825T polymorphism in the G-protein β3 subunit gene (GNB3) are associated with the efficacy of phosphodiesterase-5 inhibitor (PDE-5I) in erectile dysfunction. In addition, GNB3 genotypes could be associated with clinical worsening in pulmonary hypertension (PH) treated with PDE-5I. However, no studies have described the synergistic effects of gene polymorphisms on drug efficacy in patients with PH. OBJECTIVES: We aimed to examine the effects of combined ACE/GNB3 polymorphisms on the efficacy of PDE-5I in patients with PH. METHODS: This was a retrospective uncontrolled study. Ninety patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic PH (CTEPH) were treated with PDE-5I. Freedom from clinical worsening and pre- and post-treatment parameters, including the 6-min walk distance (6MWD) and serum brain natriuretic peptide (BNP) levels, were compared between patients with ACE/GNB3 II/TT and non-II/TT genotypes. RESULTS: Time to clinical worsening was significantly longer in patients with the II/TT genotype than in those with the non-II/TT genotype (5-year freedom from clinical worsening: 100 vs. 48.8%, respectively; p = 0.018), even in patients with CTEPH alone. Post-treatment 6MWD and BNP levels in patients with the II/TT genotype tended to be better than those in patients with the non-II/TT genotype. The ACE/GNB3 genotype was a significant predictor of clinical worsening, even after adjusting for pulmonary vascular resistance and 6MWD. CONCLUSIONS: ACE and GNB3 polymorphisms may synergistically influence the efficacy of PDE-5I in patients with PH.

Rationale: In right ventricular hypertrophy associatedwith severe pulmonary hypertension (PH), a shift of energy metabolism toward glycolysis occurs. There are few investigations regarding fatty acid metabolism in patients with PH and right ventricular hypertrophy. Objectives: To assess whether there is fatty acid accumulation in the hypertrophied right ventricle in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and to determine whether this accumulation is related to hemodynamic variables obtained by right heart catheterization. Methods: To assess fatty acid accumulation in the right ventricle, 123I-β-methyl iodophenyl pentadecanoic acid (BMIPP) analog imaging was performed in control subjects (n = 16) and patients with CTEPH (n = 13) before (n = 13) and after (n = 8) pulmonary thromboendarterectomy. Measurements and Main Results: There was increased 123IBMIPP uptake in the right ventricle of subjects with CTEPH before pulmonary endarterectomy. Right ventricular 123I-BMIPP uptake decreased significantly after thromboendarterectomy (P = 0.003) in parallel with the change of hemodynamic variables. The right ventricular BMIPP uptake was significantly correlated with the mean pulmonary artery pressure (r = 0.51, P = 0.0228) but not with pulmonary vascular resistance (r = 0.39, P = 0.0932). Conclusions: This is the first study that uses 123I-BMIPP uptake imaging to show that fatty acid accumulates in the right ventricle of patients with CTEPH and that the increased accumulation is reversible after pulmonary thromboendarterectomy. This study suggests that this imaging modality may be useful for monitoring right ventricle metabolic functions in severe PH.

BACKGROUND: Pulmonary vascular resistance (PVR) is an important parameter in the management of patients with chronic thromboembolic pulmonary hypertension (CTEPH), and numerous noninvasive methods for PVR prediction have been proposed. However, a systematic evaluation of the methods that are specific for CTEPH has not been conducted. We compared a variety of echocardiography-derived prediction indices with direct right heart catheterization (RHC) to identify the most reliable noninvasive indicator of PVR in patients with CTEPH. PATIENTS AND METHODS: Echocardiography and RHC were performed sequentially in 40 patients (mean age: 62.4±11.4 years; 30 females) with CTEPH. We measured the peak flow velocity of tricuspid regurgitation (TRV), tricuspid regurgitation pressure gradient (TRPG), right ventricular outflow tract (RVOT) time-velocity integral (TVIRVOT), left ventricular outflow tract (LVOT) time-velocity integral (TVILVOT), cardiac output at RVOT (CORVOT), and the LVOT (COLVOT) using echocardiography. The parameters TRV/TVIRVOT, TRV/TVILVOT, TRV/CORVOT, TRV/COLVOT, TRPG/TVIRVOT, TRPG/TVILVOT, TRPG/CORVOT, and TRPG/COLVOT were then calculated to predict the PVR. Finally, correlations between these echocardiographic predictors of PVR and the PVR data obtained from RHC (PVRRHC) were assessed. RESULTS: The mean pulmonary arterial pressure and PVRRHC were 32.1±11.4mmHg and 5.4±2.9 Wood units, respectively. TRV/TVIRVOT, TRV/TVILVOT, TRV/COLVOT, TRPG/TVIRVOT, TRPG/TVILVOT, TRPG/CORVOT, and TRPG/COLVOT were all significantly correlated with the PVRRHC, and TRPG/COLVOT was the most strongly correlated with the PVRRHC (r=0.807, p<0.001). CONCLUSIONS: Echocardiographic measurement of TRPG/COLVOT is a reliable noninvasive predictor of PVR in CTEPH patients.

Background Chronic thromboembolic pulmonary hypertension (CTEPH) is generally recognized to be caused by persistent organized thrombi that occlude the pulmonary arteries. The aim of this study was to investigate the characteristics of small vessel remodeling and its impact on the hemodynamics in CTEPH patients. Methods and Results Hemodynamic data were obtained from right heart catheterization in 17 CTEPH patients before pulmonary endarterectomy (PEA). Lung tissue specimens were obtained at the time of PEA. Pathological observations and evaluation of quantitative changes in pulmonary muscular arteries and veins were performed using light microscopy on 423 slides in 17 patients. The relationship between the results and the hemodynamics of CTEPH was investigated. Pulmonary arteriopathy and venopathy were recognized in most cases, although no plexiform lesions and no capillary-hemangiomatosis-like lesions were detected in any of the specimens. The severity of pulmonary arteriopathy was correlated with pulmonary vascular resistance (PVR) in the postoperative and follow-up periods. The PVR and mean pulmonary arterial pressure were significantly higher in the high-obstruction group than in the low-obstruction group. The findings in pulmonary venopathy were similar to the findings seen in pulmonary veno-occlusive disease in some cases, although severe venopathy was only observed in a portion of the pulmonary veins. There was a significant correlation between the extent of pulmonary arteriopathy and venopathy, although an effect of pulmonary venopathy to hemodynamics, including pulmonary arterial wedged pressure (PAWP), could not be identified. Conclusion The vascular remodeling of the pulmonary muscular arteries was closely associated with the hemodynamics of CTEPH. Severe pulmonary arteriopathy might be related to residual pulmonary hypertension after PEA. Those altered pulmonary arteries might be a new target for the persistent PH after the operation.

BACKGROUND: Limitations in airflow are detected in some patients with sarcoidosis in association with a poor prognosis. The impulse oscillation system (IOS) is used to treat patients with obstructive lung disease, as it can sensitively detect increased airway resistance. OBJECTIVES: To investigate the characteristics of parameters obtained with IOS in patients with sarcoidosis. METHODS: Forty-six pulmonary sarcoidosis patients at Chiba University Hospital and 20 healthy controls were enrolled. The subjects underwent IOS, pulmonary function testing and multidetector computed tomography. We evaluated the correlations between these indices in the pulmonary sarcoidosis patients and compared the pulmonary sarcoidosis patients with the healthy controls. RESULTS: The ratio of V50/V25, percentage of wall area (WA%), resistance at 5 Hz (R5) and difference between the R5 and R20 (R5-R20) values of the patients with pulmonary sarcoidosis were significantly increased compared to those observed in the controls. Inverse weak correlations were observed between the R5-R20 values and the forced expiratory volume in one second (r = -0.56; p <0.001). The R5-R20 values were correlated with the V50/V25 (r = 0.42; p < 0.005) and WA% (r = 0.43; p < 0.05) values. The WA% values were also significantly correlated with the V50/V25 (r = 0.32; p < 0.05) and R5 (r = 0.33; p < 0.05) values. CONCLUSIONS: IOS parameters were found to be significantly correlated with pulmonary function parameters and the airway wall thickness in pulmonary sarcoidosis patients. IOS is considered to be useful for detecting early manifestations of airflow limitation in pulmonary sarcoidosis patients.

Given the difficulty of diagnosing early-stage pulmonary arterial hypertension (PAH) due to the lack of signs and symptoms, and the risk of an open lung biopsy, the precise pathological features of presymptomatic stage lung tissue remain unknown. It has been suggested that the maximum elevation of the mean pulmonary arterial pressure (Ppa) is achieved during the early symptomatic stage, indicating that the elevation of the mean Ppa is primarily driven by the pulmonary vascular tone and/or some degree of pulmonary vascular remodeling completed during this stage. Recently, the examination of a rat model of severe PAH suggested that the severe PAH may be primarily determined by the presence of intimal lesions and/or the vascular tone in the early stage. Human data seem to indicate that intimal lesions are essential for the severely increased pulmonary arterial blood pressure in the late stage of the disease. However, many questions remain. For instance, how does the pulmonary hemodynamics change during the course of the disease, and what drives the development of severe PAH? Although it is generally acknowledged that both pulmonary vascular remodeling and the vascular tone are important determinants of an elevated pulmonary arterial pressure, which is the root cause of the time-dependent progression of the disease? Here we review the recent histopathological concepts of PAH with respect to the progression of the lung vascular disease.

Background and objectivePulmonary hypertension (PH) is often associated with respiratory diseases, but only a small number of patients present with severe PH defined as mean pulmonary arterial pressure35mmHg. We here conducted a multicenter, retrospective study of patients with severe PH associated with respiratory diseases (R-PH) to reveal their demographics, treatment, prognosis and determinants of prognosis. MethodsFrom 101 patients with severe R-PH collected by postal survey at the first stage, 70 patients with four major diseases (chronic obstructive pulmonary disease (COPD), combined pulmonary fibrosis with emphysema (CPFE), interstitial pneumonia associated with connective tissue disease (CTD-IP), interstitial pneumonia (IP)) and normal pulmonary arterial wedge pressure were studied for clinical characteristics, treatment and prognosis. ResultsThree-year survival rates were 50% for COPD (n=18), 35.7% for IP (n=19) and 68.1% for CTD-IP (n=20), and the 2-year survival rate for CPFE (n=13) was only 22.6%. Eighty-onepercent of patients had been treated with pharmacotherapy specific for pulmonary arterial hypertension. Those patients who had received phosphodiesterase-5 inhibitors (PDE-5I) displayed significantly better survival from the date of diagnosis than those who had not (3-year survival: 61.8% vs 20.0% P&lt;0.0001), especially in the IP, CTD-IP and CPFE groups. Multivariate analysis also revealed that treatment with PDE-5I was a positive prognostic factor. ConclusionsWe here demonstrated the dismal prognosis of patients with severe R-PH. The remarkably better survival in those patients who had received PDE-5I warrants and facilitates future prospective randomized studies in this particular population.