田邉 信宏

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.

BACKGROUND: The estimation of emphysematous changes is very sensitive to computed tomography (CT) threshold level. In clinical practice, the predetermined threshold is usually set at -950 Hounsfield units (HU) for the detection of low attenuation volume (LAV). However, threshold levels that are tightly connected to pulmonary function abnormalities have not been determined. PURPOSE: To determine the threshold level for calculating an LAV that closely reflects airflow limitation in patients with chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS: Seventy-six consecutive non-COPD smokers and COPD patients underwent paired inspiratory and expiratory multidetector CT (MDCT). LAV% was segmented every 10 HU between -1000 and -750 HU to examine the correlation between LAV% and indexes of obstructive impairment. RESULTS: LAV% gradually increased as the threshold level increased on both inspiratory and expiratory images. LAV% on inspiratory images was higher than that on expiratory images at all threshold levels between -1000 and -750 HU. The threshold level that correlated with obstructive impairment differed between the two images: -930 HU on inspiratory and -870 or -880 HU on expiratory images. CONCLUSION: LAV% dramatically changed according to the threshold level on both inspiratory and expiratory images, indicating that LAV% is dependent on the attenuation threshold level in patients with COPD. The threshold linking LAV% to airflow limitation was higher on expiratory than on inspiratory images.

We have developed a method called intersection profile method to construct a 4D-MRI (3D+time) from time-series of 2D-MRI. The basic idea is to find the best matching of the intersection profile from the time series of 2D-MRI in sagittal plane (navigator slice) and time series of 2D-MRI in coronal plane (data slice). In this study, we use 4D-MRI to semiautomatically extract the right diaphragm motion of 16 subjects (8 healthy subjects and 8 COPD patients). The diaphragm motion is then evaluated quantitatively by calculating the displacement of each subjects and normalized it. We also generate phase-length map to view and locate paradoxical motion of the COPD patients. The quantitative results of the normalized displacement shows that COPD patients tend to have smaller displacement compared to healthy subjects. The average normalized displacement of total 8 COPD patients is 9.4mm and the average of normalized displacement of 8 healthy volunteers is 15.3mm. The generated phase-length maps show that not all of the COPD patients have paradoxical motion, however if it has paradoxical motion, the phase-length map is able to locate where does it occur.

OBJECTIVE: Rapid eye movement (REM)-related sleep disordered breathing (SDB) is an entity in which the cessation or reduction of breathing occurs primarily during the REM period. Most studies have shown that REM-related SDB more frequently affects women, younger people and patients with mild or moderate SDB. The aim of this study was to prospectively investigate the prevalence and features of REM-related SDB in Japanese subjects compared with the findings of previous reports. METHODS: A total of 468 patients were evaluated in this study. The diagnosis of SDB was established using polysomnographic monitoring. The patient variables included age, gender, body characteristics, comorbidities, etc. RESULTS: REM-related SDB was more prevalent in women than non-REM-related SDB (male ratio; 66.3% vs. 79.5%, p=0.03). Moreover, the patients with REM-related SDB had lower body mass indexes (25.9 ± 6.9 vs. 28.5 ± 7.7; p=0.003), arousal indexes (31.8 ± 10.7 vs. 61.0 ± 29.1; p<0.001), apnea hypopnea indexes (15.0 ± 8.0 vs. 54.9 ± 35.9) and glycosylated hemoglobin (HbA1c) levels (5.5 ± 0.9 vs. 5.9 ± 2.6; p=0.02) than the patients with non-REM-related SDB. However, the overall and female gender prevalence of REM-related SDB among the Japanese subjects was lower than that shown in previous reports. The finding that REM-related SDB was not prevalent in younger individuals or severely obese patients was not consistent with the results of previous studies. CONCLUSION: The present findings suggest that REM-related SDB may have different clinical characteristics in the Japanese population than that observed in previous reports.

BACKGROUND: This study aimed to investigate the predictors of quality of life (QOL) in patients with chronic thromboembolic pulmonary hypertension (CTEPH), changes in QOL after surgical and medical treatments, and the relationship between baseline QOL and survival. METHODS AND RESULTS: QOL was measured in 128 patients with CTEPH (male/female: 42/86, age: 56±12 years, surgical/medical: 65/63) using the Short-Form 36 (SF-36) questionnaire. Multiple regression analysis showed pulmonary vascular resistance (PVR) and 6-min walking distance (6MWD) were associated with physical functioning (PF) (P<0.01) and physical component summary (PCS) (P<0.01). In the surgical group, 7 subscales and 2 summary scores improved significantly, and in the medical group 6 subscales and the mental component summary, although the change in QOL was greater in the surgical group. The patients in the conventional therapy group with higher PF had significantly better survival than those with lower PF (5-years survival: 89.5% vs. 50.8%, P=0.002). This difference in survival was not observed in the group receiving pulmonary arterial hypertension (PAH)-specific therapy (100% vs. 100%, P=0.746). CONCLUSIONS: PVR and 6MWD were associated with PF or PCS in CTEPH patients. QOL improved after surgical or medical therapy, with a greater change in the surgical group. PAH-specific therapy improved survival in patients with lower PF at diagnosis.

PURPOSE: Acute exacerbation (AE) is an important outcome of idiopathic pulmonary fibrosis (IPF) and nonspecific interstitial pneumonia (NSIP). Recombinant human soluble thrombomodulin (rhTM) is a new drug for the treatment of disseminated intravascular coagulation in Japan. The objective of this study was to evaluate the efficacy of rhTM for AE of IPF/NSIP. METHODS: Twenty-two patients with AE-idiopathic interstitial pneumonia (16 patients with IPF and six patients with NSIP) were enrolled in our study. Among them, eleven patients were treated with rhTM (rhTM group), and eleven patients were treated without rhTM (non-rhTM group). Patients admitted to our hospital prior to December 2013 were treated with rhTM, while those admitted after January 2014 were treated without rhTM. The primary endpoint was mortality at 90 days after AE treatment. The secondary endpoint was the safety of rhTM for AE-IPF/AE-NSIP. In addition, we examined prognostic factors of AE-IPF/AE-NSIP. RESULTS: The mortality rate was significantly lower in the rhTM group than in the non-rhTM group (mortality rate at 90 days: 36% vs 90%, P=0.023; median survival time: not reached vs 15.0 days, P=0.019). A univariate analysis revealed the respiratory rate (hazard ratio [HR] 1.09, 95% confidence interval [CI] 1.00-1.18, P=0.039) and rhTM administration (HR 0.21, 95% CI 0.06-0.77, P=0.013) as predictors of mortality at 90 days, and a multivariate analysis identified rhTM administration (HR 0.025, 95% CI 0.0006-0.94, P=0.046) as an independent predictor of mortality at 90 days. No serious adverse events were observed. CONCLUSION: The administration of rhTM is associated with reductions in mortality in patients with AE-IPF/NSIP, without causing adverse events.

Background: Pentraxin3 (PTX3) is a protein, which has multifaceted effects on innate immunity, angiogenesis, and vascular remodeling then could be a disease marker of acute myocardial infarction, heart failure, vasculitis. In addition, PTX3 has been recognized as a biomarker for pulmonary arterial hypertension, however whether it is the case in chronic thromboembolic pulmonary hypertension (CTEPH) remains unclear. Therefore, we investigated whether PTX3 would be a useful biomarker for detecting CTEPH with respect to differentiation from stable pulmonary thromboembolism (PTE), in comparison to other biomarkers. Methods: Plasma PTX3 and brain natriuretic peptide (BNP) levels were measured in 70 patients with CTEPH at their first diagnostic right heart catheterization (CTEPH group) and in 20 patients with clinically stable PTE more than three months after the acute episode (control group). The levels of plasma C-reactive protein (CRP) and heart-type fatty acid-binding protein (H-FABP) were also analyzed to compare the diagnostic ability of these biomarkers. Results: The mean level of PTX3 (ng/mL) was significantly higher in the CTEPH group than in the control group (5.51 +/- 4.53 versus 2.01 +/- 0.96, respectively), and PTX3 levels had mild negative correlation with cardiac output. BNP levels were also higher in the CTEPH group and better correlated with pulmonary hemodynamics than PTX3. However, a receiver operating characteristic (ROC) curve showed PTX3 levels were better for detecting CTEPH, and could detect CTEPH patients with less severe pulmonary hemodynamics and low plasma BNP levels. There was no significant increase in CRP and H-FABP levels in the CTEPH patients. Conclusions: Plasma PTX3 level was the most sensitive biomarker of CTEPH. Although plasma PTX3 levels did not correlate with the severity of the pulmonary hemodynamics compared to BNP, high levels in clinically stable patients following PTE should prompt a further work-up for CTEPH, which may lead to an early diagnosis.

BACKGROUND: Management of chronic thromboembolic pulmonary hypertension (CTEPH) has recently improved because of advances in pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA), and disease-targeted medications. However, patients with inoperable CTEPH or persistent pulmonary hypertension (PH) after these interventions continue to exhibit impaired exercise capacity and limited quality of life (QOL). METHODS: Eight patients with inoperable or residual CTEPH (mean age, 64±12 years; WHO functional class II/III, 6/2; mean pulmonary artery pressure, 47±13 mmHg) in stable condition and receiving disease-targeted medications participated in a 12-week home-based pulmonary rehabilitation program (muscle strength training, respiratory exercises, and walking) with supervised hospital sessions from March 2012 to January 2014. Efficacy parameters were prospectively evaluated at baseline and at completion of the 12-week program. RESULTS: After completion of the pulmonary rehabilitation program, the 6-minute walking distance (6MWD) (33.3±25.1 m), St. George׳s Respiratory Questionnaire activity score, quadriceps force, and 7-day physical activity level were significantly improved compared with baseline. All subjects completed the rehabilitation program. Although one patient experienced presyncope during the in-hospital exercise sessions, no other severe adverse events or complications of pulmonary rehabilitation were observed. CONCLUSIONS: These findings suggest that home-based pulmonary rehabilitation with closely supervised sessions may safely improve exercise capacity, leg muscle strength, general activity in daily life and health-related QOL in CTEPH patients.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation caused by emphysema and small airway narrowing. Quantitative evaluation of airway dimensions by multi-detector computed tomography (MDCT) has revealed a correlation between airway dimension and airflow limitation. However, the effect of emphysema on this correlation is unclear. OBJECTIVE: The goal of this study was to determine whether emphysematous changes alter the relationships between airflow limitation and airway dimensions as measured by inspiratory and expiratory MDCT. METHODS: Ninety-one subjects underwent inspiratory and expiratory MDCT. Images were evaluated for mean airway luminal area (Ai), wall area percentage (WA%) from the third to the fifth generation of three bronchi (B1, B5, B8) in the right lung, and low attenuation volume percent (LAV%). Correlations between each airway index and airflow limitation were determined for each patient and compared between patients with and without evidence of emphysema. RESULTS: In patients without emphysema, Ai and WA% from both the inspiratory and expiratory scans were significantly correlated with FEV1. No correlation was detected in patients with emphysema. In addition, emphysematous COPD patients with GOLD stage 1 or 2 disease had significantly lower changes in B8 Ai than non-emphysematous patients. CONCLUSIONS: A significant correlation exists between airway parameters and FEV1 in patients without emphysema. Emphysema may influence airway dimensions even in patients with mild to moderate COPD.

Background: Epidemiology and clinical management of acute venous thromboembolism (VTE) are not readily available in Japan. Methods and Results: The Japan VTE Treatment Registry (JAVA) is a multicenter cohort study of consecutive patients with an objectively confirmed, symptomatic acute pulmonary embolism (PE), symptomatic acute deep vein thrombosis (DVT), or asymptomatic acute proximal DVT. Of the 1,076 patients enrolled with acute VTE, 68.7% presented with an isolated DVT; 17.0% had PE alone; and 14.4% had both. VTE management was characterized by a high rate of inferior vena cava filter insertion (40.6%), frequent thrombolysis (21.1%), and sub-therapeutic unfractionated heparin-based anticoagulation, followed by warfarin prescription, mostly targeting an international normalized ratio of 2.0 (range, 1.5-2.5). During a mean observation period of 252.5 days, 29 recurrent cases of VTE were documented, yielding an incidence rate of 3.9 per 100 patient-years. A total of 123 patients died during the study period, corresponding to a rate of 16.6 deaths per 100 patient-years. The incidence of major bleeding was 3.2% per patient-year, including 2 fatal hemorrhages and 7 intracranial hemorrhages. Conclusions: VTE management in Japan is characterized by a highly aggressive strategy in the acute phase, in contrast to protocols that use low-level anticoagulation. The VTE recurrence rates in Japan and Western countries are similar, but mortality is higher in Japan, with significant variability depending on patient and management characteristics.

Sarcoma-like cells (SCLs) were derived from endarterectomized tissue of a single chronic thromboembolic pulmonary hypertension (CTEPH) patient during incubation of those thrombi at second passage as described at our previous report. These cells had malignant potential, with an increased expression of matrix metalloproteinase-14 (MMP-14), leading to tumor emboli within pulmonary arteries in in vivo studies. The purpose of this study was to perform a more detailed evaluation of the characteristics of SCLs, and to elucidate the role of the increased expression of MMP-14 expression in the growth and death of these cells. In order to elucidate the characteristics of SCLs and to confirm the protein expression of MMP-14, three-dimentional culture, invasion assays, a Western blot analysis and immunohistochemical studies were performed. To examine the role of MMP-14 in tumorigenesis, the metalloproteinase inhibitor, batimastat, was administered to SCID mice which were subcutaneously injected with SCLs. Those mice were sacrificed on day 14 and the tumor volume was evaluated. A Western blot analysis showed the increased expression of MMP-14 in comparison to the expression in lung adenocarcinoma cells (A549). Immunohistochemistry showed that SCLs were positive for vimentin, MMP-14, MMP-2 and CD44. However, endothelial markers, such as CD31 and von Willebrand factor (vWF), were negative. The in vivo studies demonstrated that batimastat could suppress the growth of the subcutaneous tumors formed by the SCLs. This study suggested that MMPs had critical roles on the pathological activities of SCLs and that batimastat might have anti-proliferative and anti-invasive effects on these cells.

A 48-year-old woman was diagnosed with idiopathic pulmonary arterial hypertension (PAH) and administered PAH-specific therapies, including bosentan. Four years after the initiation of treatment with bosentan, liver dysfunction appeared, and ambrisentan was substituted for bosentan. One-and-a half years later, a second episode of liver dysfunction occurred. The pathological findings of a liver biopsy specimen were not definitive, although drug-induced hepatotoxicity caused by ambrisentan was considered. However, the patient's liver dysfunction did not improve even after the discontinuation of ambrisentan. Finally, we diagnosed her with autoimmune hepatitis (AIH). Providing careful observation with a suspicion of AIH is important when treating PAH patients with autoantibodies.

A 47-year-old woman with idiopathic pulmonary arterial hypertension (IPAH) was referred to our hospital for treatment of an ovarian tumor. Although chest contrast-enhanced CT scans obtained on admission revealed pulmonary arterial thrombosis, she was diagnosed with IPAH with central pulmonary thrombosis based on a normal perfusion lung scan. We initiated upfront triple combination therapy with pulmonary vasodilators. After one month of the therapy, the patient's pulmonary hemodynamics improved. Gynecological surgery was performed under general anesthesia without any perioperative complications. Providing careful intensive management of patients with severe PAH can reduce the perioperative risks of non-cardiac and non-obstetric surgery.

Background: Pulmonary hypertension (PH) often correlates with respiratory disease severity. Right heart catheterization (RHC) is recommended for the definitive diagnosis of PH associated with respiratory disease (R-PH). However, no previous studies have evaluated the perceived necessity for pulmonologists to use RHC for R-PH diagnosis, or the management of R-PH in Japan. Methods: Questionnaires were mailed to 855 institutions, approved by the Japanese Respiratory Society. Questions included the prevalence and necessity of RHC and other methods in R-PH diagnosis, and current trends in the treatment of R-PH. Results: Questionnaires were returned from 289 institutions (34%). Patients with R-PH were examined by pulmonologists in 89% of institutions some pulmonologists performed echocardiography (15%) and some RHC (13%). Echocardiography was used to diagnose R-PH in 99% of institutions and RHC was used in 36%. RHC was considered in cases of suspected PH in 49% of institutions and prior to initiation of pulmonary arterial hypertension (PAH)-specific therapy in 57%. Of patients diagnosed with R-PH, 47% were treated with ambulatory oxygen therapy. Furthermore, 98 of 145 institutions used PAH-specific therapy to treat R-PH. Of the 1355 patients who underwent RHC as a part of PH evaluation, 29% were confirmed to have PH, and 8% had severe PH with a mean pulmonary arterial pressure of ≥35. mmHg. Conclusions: The current diagnostic and treatment modalities for R-PH in Japan were evaluated. Although few pulmonologists perform RHC for R-PH diagnosis in Japan, more than half consider using RHC for patients before initiating PAH-specific therapy. © 2013 The Japanese Respiratory Society.

BACKGROUND: It is unclear whether abnormalities of coagulation or fibrinolysis are associated with disease progression of chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this study was to investigate the association of these factors with the severity and prognosis of CTEPH. METHODS AND RESULTS: Between 1986 and 2011, plasma fibrinogen and plasminogen were measured in 89 of 106 consecutive patients with inoperable CTEPH (17 men; mean age, 55.9±14.1 years old; mean pulmonary arterial pressure, 44.0±12.4 mmHg) and the association of level with severity and prognosis were also examined. Seventeen patients had high fibrinogen and low plasminogen (medians, ≥291 mg/dl and <101%, respectively). These patients had significantly lower cardiac index (2.26±0.68 vs. 2.70±0.57 L·min(-1)·m(-2), P=0.007), higher pulmonary vascular resistance (PVR; 13.29±7.54 vs. 9.15±4.14 Wood units, P=0.003), and poor survival (5-year survival, 35.3% vs. 88.0%, P<0.001) compared to the other 72 patients. Additional analysis showed significantly poor survival in these patients compared with the other patients who did not have modern therapy. On multivariate analysis plasma fibrinogen, plasminogen and PVR were independent predictors of survival in medically treated patients. CONCLUSIONS: High plasma fibrinogen and low plasminogen are associated with poor survival in CTEPH patients without modern therapy.

OBJECTIVE: Laboratory-based polysomnography (PSG) is the gold standard for diagnosing obstructive sleep apnea-hypopnea syndrome (OSAHS), but it is expensive and requires overnight hospitalization. Recently, a sheet-shaped breath detection monitor, the SD-101, has been developed, and several reports have so far demonstrated the screening accuracy of this device. The aim of this study was to assess the accuracy and the uncertainty of this device. METHODS: A total of 101 suspected OSAHS patients underwent simultaneous examinations with PSG and the SD-101. RESULTS: There was a statistically significant relationship between the respiratory disturbance index (RDI) by the SD-101 and the apnea-hypopnea index (AHI) by PSG. At an RDI cutoff of 14 episodes per hour, the sensitivity and specificity to detect an AHI ≥20 episodes per hour were 90.2% and 90.0%, respectively. To reduce the influence of sleep efficiency, the time in bed (TIB) obtained from PSG, instead of the total seep time (TST), was used to calculate the AHI from the PSG data. There was also a statistically significant relationship between the RDI and AHI for the TIB. Moreover, it was suggested that arousal index and TIB were likely associated with false-negative and/or false-positive results. CONCLUSION: Although the present study demonstrated a close relationship between the RDI and the AHI, use of the SD-101 to examine symptomatic OSAHS patients should be performed with a full understanding of its incapability to detect the sleep state, including arousal reaction and the existence of false respiratory events caused by body movements.

Objective Beraprost was developed as the first oral prostacyclin analog to treat patients with pulmonary arterial hypertension (PAH). Although this drug demonstrates improvements in the patient's exercise capacity and symptoms, it carries a weak recommendation in the PAH evidence-based treatment algorithm due to a lack of durability of effects. However, this therapy remains a major treatment method in Japan due to its availability and inexpensive cost. The purpose of this study was to elucidate whether this drug exhibits durable effects on sustained overall survival. Methods A comparison of survival benefits was completed among patients undergoing treatment with beraprost (n=35) or conventional therapy (n=44). In addition, the estimated survival calculated using the equation developed by the National Institutes of Health Registry was used for the analysis. Results Although no significant differences were observed between the two groups using the Kaplan-Meier survival curve, a statistical difference was observed between the patients receiving high-dose beraprost therapy (&gt;120 mu g) and those receiving conventional therapy (5- and 10-year survival: 71.1% and 49.4% vs. 37.7% and 21.2%, respectively; p=0.0466). Moreover, the cumulative survival rates in the patients receiving beraprost were slightly better than the estimated survival rates. In the PAH patients with connective tissue diseases, a tendency towards better survival outcomes was observed in the group treated with beraprost. Conclusion This study suggests the survival benefits of high-dose beraprost therapy for patients with PAH. The retrospective nature of this study, however, makes it difficult to conclude definitively that beraprost exerts significant beneficial effects on survival.

Objective We aimed to investigate the incidence and clinical characteristics of nontuberculous mycobacterial (NTM) pulmonary disease as a complication of chronic thromboembolic pulmonary hypertension (CTEPH). Methods We conducted a retrospective study of 10 cases (5.6%) complicated by NTM pulmonary disease among 180 CTEPH patients. Results Isolated species of avium (n=5), kansasii (n=2), intracellulare (n=1), abscessus (n=1) and fortuitum (n=1) were detected. NTM-infected lesions were observed in 33 of 180 (18.3%) lung segments obtained from the 10 patients, and complete obstruction due to chronic pulmonary thromboembolism was detected in 65 of the 180 segmental pulmonary arteries (36.1%). The NTM-infected segments in the CTEPH patients were significantly associated with obstructed rather than unobstructed pulmonary artery segments [25 of 65 (38.5%) vs. 8 of 115 (6.9%), p&lt;0.01]. Cavitary, nodular, ectatic and ground-glass lesions were seen in 14, 22, seven and four of the 180 segments, respectively. Thirteen of the 14 cavitary (92.9%) lesions were located in non-perfused segments. Five patients with NTM disease underwent pulmonary endarterectomy (PEA). Of the 18 assessable NTM-infected segments in six NTM-treated patients, 17 were located in non-perfused segments and one was located in a previously perfused segment. All NTM-infected segments improved among three segments reperfused with PEA. In contrast, only eight (57.1%) NTM-infected segments improved among 14 continuously non-perfused segments. A lower body mass index was found to be a significant risk factor for NTM disease in the CTEPH patients. Conclusion This is the first report to document NTM-disease complications in patients with CTEPH. Reperfusion in cases of NTM lesions may improve the response to NTM drug therapy.

A 17-year-old Japanese girl visited our hospital for an evaluation of exertional dyspnea. A diagnosis of pulmonary arterial hypertension (PAH) was confirmed based on the findings of right heart catheterization. Detailed questioning revealed a family history of hereditary hemorrhagic telangiectasia (HHT), and a genetic mutation analysis disclosed a mutation in the activin receptor-like kinase 1 gene (ACVRL1). The patient was finally diagnosed with HHT according to the Curaçao diagnostic criteria eight years after the diagnosis of PAH. This case supports previous reports indicating that signs of PAH can be the first manifestation of disease in ACVRL1 mutation carriers.

BACKGROUND: We aimed to study whether pulmonary arterial distensibility (PAD) correlates with hemodynamic parameters in chronic thromboembolic pulmonary hypertension (CTEPH) using electrocardiogram (ECG)-gated 320-slice multidetector computed tomography (MDCT). METHODS AND FINDINGS: ECG-gated 320-slice MDCT and right heart catheterization (RHC) was performed in 53 subjects (60.6±11.4 years old; 37 females) with CTEPH. We retrospectively measured the minimum and maximum values of the cross sectional area (CSA) of the main pulmonary artery (mainPA), right pulmonary artery (rtPA), and left pulmonary artery (ltPA) during one heartbeat. PAD was calculated using the following formula: PAD = [(CSAmaximum-CSAminimum)/CSAmaximum]×100(%). The correlation between hemodynamic parameters and PAD was assessed. Mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) were 40.8±8.7 mmHg and 8.3±3.0 wood units, respectively. PAD values were as follows: mainPA (14.0±5.0%), rtPA (12.8±5.6%), and ltPA (9.7±4.6%). Good correlations existed between mainPAD, with mPAP (r = -0.594, p<0.001) and PVR (r = -0.659, p<0.001). The correlation coefficients between rtPAD and ltPAD with pulmonary hemodynamics were all lower or equal than for mainPAD. CONCLUSIONS: PAD measured using ECG-gated 320-slice MDCT correlates with pulmonary hemodynamics in subjects with CTEPH. The mainPA is suitable for PAD measurement.

Cancer chemotherapy, including molecular targeted therapy, has major limitations because it does not kill all the cancer cells; the residual cells survive until they acquire chemoresistance. In the present study, the combined effects of metformin and gefitinib were examined in vivo in a mouse xenograft model, inoculated with a human lung adenocarcinoma cell line that possesses an activating epidermal growth factor receptor mutation. The mechanism of the interaction was further elucidated in vitro. Metformin did not suppress the growth of already established tumors, nor did metformin augment tumor shrinkage by gefitinib. However, metformin significantly suppressed the regrowth of the tumor after effective treatment with gefitinib, suggesting the specific effect of metformin on the residual cells. Cytotoxicity of metformin was characterized by the absence of apoptosis induction and unremarkable cell cycle shift in vitro. The residual cell population after treatment with gefitinib was characterized by enriched cells with high expression of CD133 and CD24. Metformin was still effective on this specific cell population. Targeting residual cells after chemotherapy may represent an effective novel strategy for the treatment of cancer. Elucidating the mechanism of metformin cytotoxicity provides insights into future development of anticancer therapeutics.

OBJECTIVES: Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases. MATERIALS AND METHODS: Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm(2) as well as the percentage LAA for total lung area (%CSA<5, %LAA, respectively) were calculated. RESULTS: The %CSA<5 correlated negatively with %LAA. The %CSA<5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA<5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA<5 in COPD patients was greater than that in non-COPD smokers. CONCLUSION: The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension caused by non-resolving thromboembolisms of the pulmonary arteries. In Japan, in contrast to Western countries, CTEPH is more prevalent in women. A Japanese multicenter study reported that a form of CTEPH unrelated to deep vein thrombosis is associated with HLA-B*5201, suggesting that this form of CTEPH may be associated with vasculopathy. CTEPH can be cured by pulmonary endarterectomy, provided that the thrombi are surgically accessible thus, early diagnosis is important, and all patients with exertional dyspnea should be evaluated for pulmonary hypertension. Ventilation/perfusion scans provide an excellent non-invasive means to distinguish CTEPH from pulmonary arterial hypertension. Similarly, computed tomographic pulmonary angiograms allow for the detection of thrombi and evaluation of pulmonary hemodynamics in a minimally invasive manner. Importantly, the absence of subpleural perfusion on pulmonary angiograms can suggest the presence of small vessel disease. Small vessel disease might be involved in the pathogenesis of CTEPH, and its detection is essential in preventing operative death. Although no modern therapies for pulmonary arterial hypertension have been approved for treatment of CTEPH, a recent randomized control trial of riociguat in patients with CTEPH demonstrated that riociguat significantly improved 6-min walking distance. Further investigations into treatments that target endothelial dysfunction and hyperproliferative CTEPH cells are needed. Recently, balloon pulmonary angioplasty has emerged as a promising treatment modality in Japan. A specialized medical team, including at least one expert surgeon, should make decisions regarding patients' candidacy for pulmonary endarterectomy and/or balloon pulmonary angioplasty. © 2013 The Japanese Respiratory Society.

Background: The surgical indication for chronic thromboembolic pulmonary hypertension (CTEPH) has been modified due to recognition of peripheral type CTEPH and changes in surgical methods and skill. Bosentan and sildenafil are used as modern oral therapy (mod Tx) in patients with inoperable CTEPH, although it remains unknown whether they have positive effects on survival. Methods and Results: A total of 202 patients were diagnosed with CTEPH at Chiba University Hospital between 1986 and 2010, 100 of whom underwent pulmonary endarterectomy. Seven medically treated patients with pulmonary vascular resistance (PVR) &lt;= 300 dyn . s . cm(-5) were regarded as having mild disease. Survival rate was stratified by date of diagnosis (group 1, 1986-1998; group 2, 1999-2004; group 3, 2005-2010), and prognostic factors in the remaining 95 medically treated patients were investigated. Group 3 included the most patients treated with mod Tx (group 1, 9.1%; group 2, 24.2%; group 3, 65.0%) and had significantly better survival than either group 1 or 2 (5-year survival: group 1, 54.6%; group 2, 69.7%; group 3, 87.3%). Patients receiving mod Tx had significantly better survival than those not on mod Tx (5-year survival: 88.9% vs. 60.2%). Multivariate analysis showed that mod Tx, lower PVR, and lack of comorbidity were significant predictors of better outcome. Conclusions: Medically treated patients with CTEPH had a better survival rate, and the use of mod Tx contributed to improved survival.

BACKGROUND: Right-sided heart catheterization (RHC) and pulmonary digital subtraction angiography (PDSA) are the standard methods used in diagnosing suspected or defi nite chronic thromboembolic pulmonary hypertension (CTEPH). We studied the ability of 320-slice CT imaging to detect simultaneously chronic thromboembolic fi ndings in the pulmonary arteries and pulmonary hemodynamics based on the curvature of the interventricular septum (IVS) in CTEPH . METHODS: Forty-four patients with high clinical suspicion of CTEPH underwent RHC, PDSA, and enhanced double-volume retrospective ECG-gated 320-slice CT scan. We measured the sensitivity and specificity of CT imaging to detect thrombi in the pulmonary arteries compared with PDSA. We also compared IVS bowing (expressed as curvature) measured on the short-axis cine heart image with pulmonary arterial pressure (PAP) obtained by RHC. RESULTS: Compared with PDSA, the sensitivity and specificity of CT imaging to detect chronic thromboembolic findings were 97.0% and 97.1% at the main/lobar level and 85.8% and 94.6% at the segmental level, respectively. The correlation coefficients of IVS curvature with systolic PAP and mean PAP were 2 0.79 ( P , .001) and 2 0.86 ( P , .001), respectively. CONCLUSIONS: The use of 320-slice CT imaging allows for less invasive and simultaneous detection of thrombi and evaluation of pulmonary hemodynamics for the diagnostic work-up of CTEPH.