Efficacy and Safety of Warfarin for the Treatment of Venous Thromboembolism　- A Multicenter Prospective Observational Cohort Study in Japan (AKAFUJI Study).

BACKGROUND: A large-scale prospective study of the efficacy and safety of warfarin for the treatment of venous thromboembolism (VTE) has not been conducted in Japan. Therefore, we conducted a real-world prospective multicenter observational cohort study (AKAFUJI Study; UMIN000014132) to investigate the efficacy and safety of warfarin for VTE.Methods and Results: Between May 2014 and March 2017, 352 patients (mean [±SD] age 67.7±14.8 years; 57% female) with acute symptomatic/asymptomatic VTE were enrolled; 284 were treated with warfarin. The cumulative incidence of recurrent symptomatic VTE was higher in patients without warfarin than in those treated with warfarin (8.7 vs. 2.2 per 100 person-years, respectively; P=0.018). The cumulative incidence of bleeding complications was not significantly different between the 2 groups. The mean prothrombin time-international normalized ratio (PT-INR) during warfarin on-treatment was <1.5 in 180 patients, 1.5-2.5 in 97 patients, and >2.5 in 6 patients. The incidence of bleeding complications was significantly higher in patients with PT-INR >2.5, whereas the incidence of recurrent VTE was not significantly different between the 3 PT-INR groups. The cumulative incidence of recurrent VTE and bleeding complications did not differ significantly among those in whom VTE was provoked by a transient risk factor, was unprovoked, or was associated with cancer. CONCLUSIONS: Warfarin therapy with an appropriate PT-INR according to Japanese guidelines is effective without increasing bleeding complications, regardless of patient characteristics.

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

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

Possible Protective Effect of Remote Ischemic Preconditioning on Acute Kidney Injury Following Elective Percutaneous Coronary Intervention: Secondary Analysis of a Multicenter, Randomized Study.

Remote ischemic preconditioning (RIPC) is a promising strategy for protecting against ischemic reperfusion injury. This study is a secondary analysis of a randomized study that aimed to evaluate the effect of RIPC on the early increase in serum creatinine (SCr) following percutaneous coronary intervention (PCI), which is associ-ated with contrast-induced acute kidney injury. Patients with stable angina undergoing elective PCI were assigned to control, RIPC, and continuous infusion of nicorandil (nicorandil) groups. The endpoint of this study was the incidence of the early increase in SCr, a predictor of contrast-induced acute kidney injury, which was defined as either a > 20% or absolute increase by 0.3 mg/dl of SCr levels after 24 h of PCI. This study included 220 patients for whom a dataset of SCr values was available. The incidence of the early increase in SCr was significantly lower in the RIPC than in the control (1.3% vs 10.8%, p = 0.03) group, but was not significantly different between the nicorandil and control groups. In multivariate analysis, RIPC remained a significant fac-tor associated with a reduction in the incidence of early increase in SCr. RIPC reduces the incidence of early increase in SCr in patients with stable angina following elective PCI.

The effect of luseogliflozin and alpha-glucosidase inhibitor on heart failure with preserved ejection fraction in diabetic patients: rationale and design of the MUSCAT-HF randomised controlled trial.

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is a strong risk factor for coronary artery disease and heart failure, particularly heart failure with preserved ejection fraction (HFpEF). The aim of the ongoing MUSCAT-HF (It stands for Prospective Comparison of Luseogliflozin and Alpha-glucosidase on the Management of Diabetic Patients with Chronic Heart Failure and Preserved Ejection Fraction) trial is to evaluate the efficacy of luseogliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, versus voglibose, an alpha-glucosidase inhibitor, using brain natriuretic peptide (BNP) as the index of therapeutic effect in T2DM patients with HFpEF. METHODS AND ANALYSIS: A total of 190 patients with T2DM and HFpEF (ejection fraction >45%) who are drug-naïve or taking any anti-diabetic agents will be randomised (1:1) to receive luseogliflozin 2.5 mg one time per day or voglibose 0.2 mg three times per day. The patients will be stratified by age (<65 years, ≥65 years), baseline haemoglobin A1c (<8.0%, ≥8.0%), baseline BNP (<100 pg/mL, ≥100 pg/mL), baseline renal function (estimated glomerular filtration rate ≥60 mL/min/1.73 m2, <60 mL/min/1.73 m2), use of thiazolidine or not and presence or absence of atrial fibrillation and flutter at screening. After randomisation, participants will receive the study drug for 12 weeks in addition to their background therapy. The primary endpoint is the proportional change in baseline BNP after 12 weeks of treatment. The key secondary endpoints are the change from baseline in the ratio of early mitral inflow velocity to mitral annular early diastolic velocity, body weight and glycaemic control after 12 weeks of treatment. ETHICS AND DISSEMINATION: The study has been approved by the ethics committee and the patients will be included after informed consent. The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: UMIN000018395.

Tobacco smoking protective effect via remote ischemic preconditioning on myocardial damage after elective percutaneous coronary intervention: Subanalysis of a randomized controlled trial.

BACKGROUND: Remote ischemic preconditioning (RIPC) is promising for preventing periprocedural myocardial damage (pMD) in patients undergoing percutaneous coronary intervention (PCI). However, the impact of RIPC on pMD on smokers is not well elucidated. The aim of this study was to investigate an association between tobacco smoking and RIPC on pMD in patients planning to undergo PCI. METHODS: This study used data from a multicenter randomized controlled trial involving patients with stable angina who planned to undergo elective PCI. We analyzed data for 262 patients in the control (n = 133) and upper-limb RIPC (n = 129) groups, including 166 current or former smokers. The major outcome was the pMD incidence following PCI, with pMD defined as an elevated level of highly sensitive cardiac troponin T or a creatine kinase myocardial band 12 or 24 h after PCI. RESULTS: The incidence of pMD was significantly lower in the upper-limb RIPC group than in the control group (28/83 patients [33.8%] vs. 43/83 patients [51.8%], respectively; p = 0.018). In a multiple logistic regression model, tobacco smoking was an independent predictor of interacting with and enhancing the effect of RIPC on reducing the incidence of pMD after PCI (regression coefficient, -0.4 [95% confidence interval, -0.74 to -0.082]; p = 0.015). CONCLUSIONS: Tobacco smoking may have a beneficial effect on RIPC against pMD after PCI.

Protective effect of nicorandil on myocardial injury following percutaneous coronary intervention in older patients with stable coronary artery disease: Secondary analysis of a randomized, controlled trial (RINC).

BACKGROUND: Our previous study examined an effect of remote ischemic preconditioning (RIPC) or intravenous nicorandil on reduction of periprocedural myocardial injury (pMI) following percutaneous coronary intervention (PCI) in patients with stable coronary artery disease (CAD). We further investigated the effect of RIPC or nicorandil on pMI in older patients. METHODS: Patients with stable CAD who planned to undergo PCI were assigned to a 1:1:1 ratio to control, intravenous nicorandil, or upper-limb RIPC groups. This substudy analyzed patients aged >65 years (n = 282) from the principal cohort. The primary outcome was the incidence of pMI following PCI. We defined pMI as an elevated level of high-sensitive cardiac troponin T or creatine kinase myocardial band 12 or 24 hours after PCI. RESULTS: We found that pMI following PCI was significantly reduced in the nicorandil group compared with the control group (37.2% vs. 53.7%, multiplicity-adjusted p = 0.046), but not in the RIPC group compared with the control group (43.0% vs. 53.7%, multiplicity-adjusted p = 0.245). The adjusted odds ratios (95% confidence interval) for pMI in the RIPC and nicorandil groups versus the control group were 0.63 (0.34 to 1.16) and 0.51 (0.27 to 0.96), respectively. CONCLUSION: Intravenous nicorandil significantly reduces pMI following PCI in a subgroup of older patients with stable CAD. Phase 3 trials are required to validate our results. TRIAL REGISTRATION: UMIN Clinical Trials Registry UMIN000005607.

Protective Effect of Remote Ischemic Preconditioning on Myocardial Damage After Percutaneous Coronary Intervention in Stable Angina Patients With Complex Coronary Lesions　- Subanalysis of a Randomized Controlled Trial.

BACKGROUND: The effect of remote ischemic preconditioning (RIPC) on periprocedural myocardial damage (pMD) in patients undergoing percutaneous coronary intervention (PCI) is controversial. The aim of this study was to investigate the effect of RIPC or intravenous nicorandil on pMD following elective PCI in a subgroup of patients with complex coronary lesions from a multicenter randomized controlled trial.Methods and Results:Patients with stable angina who underwent elective PCI were assigned to 3 groups: control, upper-limb RIPC or intravenous nicorandil. The major outcome was pMD incidence following PCI, with pMD defined as an elevated level of high-sensitivity cardiac troponin T or creatine kinase myocardial band at 12 or 24 h after PCI. A total of 171 patients with complex coronary lesions (ACC-AHA coronary classification type B2 or C) were analyzed. The incidence of pMD following PCI was significantly lower in the RIPC group than in the control group (44.4% vs. 66.1%; P=0.023). The adjusted odds ratio (95% confidence interval) for pMD in the RIPC vs. the controls was 0.41 (0.18-0.94). The incidence of pMD in the nicorandil group was not significantly reduced compared with the control groups. CONCLUSIONS: This substudy suggested that RIPC prior to PCI prevented pMD in patients with complex coronary lesions. Further investigation in a multicenter prospective study is needed to confirm these results.

Effect of Intensive and Standard Pitavastatin Treatment With or Without Eicosapentaenoic Acid on Progression of Coronary Artery Calcification Over 12 Months　- Prospective Multicenter Study.

BACKGROUND: The effect of lipid-lowering agents on progression of coronary artery calcification (CAC) remains unclear. We evaluated the effects of pitavastatin 2 mg/day (PIT2), pitavastatin 4 mg/day (PIT4), and PIT2 combined with eicosapentaenoic acid (PIT2+EPA) on CAC progression.Methods and Results:This prospective multicenter study in Japan included patients with an Agatston score of 1-999, hypercholesterolemia, and no evidence of cardiovascular disease. Patients were allocated into PIT2, PIT4, or PIT2+EPA groups. The primary outcome was the annual percent change in Agatston score in all patients. In total, 156 patients who had multi-detector row computed tomography without any artifacts were included in the primary analysis. Pitavastatin did not significantly reduce the annual progression rate of the Agatston score (40%; 95% CI: 19-61%). The annual progression rate of Agatston score in the PIT2 group was not significantly different from that in the PIT4 group (34% vs. 42%, respectively; P=0.88) or the PIT2+EPA group (34% vs. 44%, respectively; P=0.80). On post-hoc analysis the baseline ratio of low- to high-density lipoprotein cholesterol was a significant predictor of non-progression of Agatston score by pitavastatin (OR, 2.17; 95% CI: 1.10-44.12; P=0.02). CONCLUSIONS: Pitavastatin does not attenuate progression of CAC. Intensive pitavastatin treatment and standard treatment with EPA does not reduce progression of CAC compared with standard treatment.

Effect of remote ischemia or nicorandil on myocardial injury following percutaneous coronary intervention in patients with stable coronary artery disease: A randomized controlled trial.

BACKGROUND: The effect of remote ischemic preconditioning (RIPC) and nicorandil on periprocedural myocardial injury (pMI) in patients with planned percutaneous coronary intervention (PCI) remains controversial. The aim of this randomized trial was to evaluate the effect of RIPC or nicorandil on pMI following PCI in patients with stable coronary artery disease (CAD) compared with a control group. METHODS: Patients with stable CAD who planned to undergo PCI were assigned to a 1:1:1 ratio to control, RIPC, or intravenous nicorandil (6mg/h). Automated RIPC was performed by a device, which performs intermittent arm ischemia through three cycles of 5min of inflation and 5min of deflation of a pressure cuff. The primary outcome was the incidence of pMI, determined by an elevation in high-sensitive troponin T or creatine kinase myocardial band at 12 or 24h after PCI. The secondary outcomes were ischemic events during PCI and adverse clinical events at 8months after PCI. RESULTS: A total of 391 patients were enrolled. The incidence of pMI following PCI was not significantly different between the control group (48.9%) and RIPC group (39.5%; p=0.14), or between the control group and nicorandil group (40.3%; p=0.17). There were no significant differences in ischemic events during PCI or adverse clinical events within 8months after PCI among the three groups. CONCLUSIONS: This study demonstrated moderate reductions in biomarker release and pMI by RIPC or intravenous nicorandil prior to the PCI consistently, but may have failed to achieve statistical significance because the study was underpowered.

Novel Angiographic Classification of Each Vascular Lesion in Chronic Thromboembolic Pulmonary Hypertension Based on Selective Angiogram and Results of Balloon Pulmonary Angioplasty.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is an alternative therapy for patients with chronic thromboembolic pulmonary hypertension who are ineligible for standard therapy, pulmonary endarterectomy. Although there are several classifications of vascular lesions, these classifications are based on the features of the specimen removed during pulmonary endarterectomy. Because organized thrombi are not removed during balloon pulmonary angioplasty, we attempted to establish a new classification of vascular lesions based on pulmonary angiographic images. We evaluated the success and complication rate of BPA in accordance with the location and morphology of thromboembolic lesions. METHODS AND RESULTS: We reviewed 500 consecutive procedures (1936 lesions) of BPA in 97 patients with chronic thromboembolic pulmonary hypertension and investigated the outcomes of BPA based on the lesion distribution and the angiographic characteristics of the thromboembolic lesions, as follows: type A, ring-like stenosis lesion; type B, web lesion; type C, subtotal lesion; type D, total occlusion lesion, and type E, tortuous lesion. The success rate was higher, and the complication rate was lower in ring-like stenosis and web lesions. The total occlusion lesions had the lowest success rate. Tortuous lesions were associated with a high complication rate and should be treated only by operators with extensive experience with BPA. CONCLUSIONS: We modified the previous angiographic classification and established a new classification for each vascular lesion. We clarified that the outcome and complication rate of the BPA are highly dependent on the lesion characteristics.

Pulmonary microvascular remodeling after balloon pulmonary angioplasty in a patient with chronic thromboembolic pulmonary hypertension.

We herein report a case of peripheral type chronic thromboembolic pulmonary hypertension treated with medical therapy and subsequent balloon pulmonary angioplasty (BPA). After a series of BPA procedures, the patient's hemodynamics almost completely normalized. The patient was later diagnosed with lung carcinoma, and the vasculature of the resected lung demonstrated intimal thickening and luminal stenosis in the pulmonary arteries in both the areas where BPA was performed and not performed, in spite of a marked reduction in pulmonary arterial pressure. The present case is the first report on the histology of the pulmonary vasculature following BPA.

Refined balloon pulmonary angioplasty for inoperable patients with chronic thromboembolic pulmonary hypertension.

BACKGROUND: Although balloon pulmonary angioplasty (BPA) for inoperable patients with chronic thromboembolic pulmonary hypertension was first reported over a decade ago, its clinical application has been restricted because of limited efficacy and complications. We have refined the procedure of BPA to maximize its clinical efficacy. METHODS AND RESULTS: Sixty-eight consecutive patients with inoperable chronic thromboembolic pulmonary hypertension underwent BPA. We evaluated pulmonary artery diameters and determined the appropriate balloon size by using intravascular ultrasound. We performed BPA in a staged fashion over multiple, separate procedures to maximize efficacy and reduce the risk of reperfusion pulmonary injury. A total of 4 (2-8) sessions were performed in each patient, and the number of vessels dilated per session was 3 (1-14). The World Health Organization functional class improved from 3 to 2 (P<0.01), and mean pulmonary arterial pressure was decreased from 45.4 ± 9.6 to 24.0 ± 6.4 mm Hg (P<0.01). One patient died because of right heart failure 28 days after BPA. During follow-up for 2.2 ± 1.4 years after the final BPA, another patient died of pneumonia, and the remaining 66 patients are alive. In 57 patients who underwent right heart catheterization at follow-up, improvement of mean pulmonary arterial pressure was maintained (24.0 ± 5.8 mm Hg at 1.0 ± 0.9 years). Forty-one patients (60%) developed reperfusion pulmonary injury after BPA, but mechanical ventilation was required in only 4 patients. CONCLUSIONS: Our refined BPA procedure improves clinical status and hemodynamics of inoperable patients with chronic thromboembolic pulmonary hypertension, with a low mortality. A refined BPA procedure could be considered as a therapeutic approach for patients with inoperable chronic thromboembolic pulmonary hypertension.

Multidetector-row computed tomography-based clinical assessment of fondaparinux for treatment of acute pulmonary embolism and acute deep vein thrombosis in Japanese patients.

BACKGROUND: Unfractionated heparin (UFH) is the standard drug for the initial treatment of pulmonary embolism (PE) and deep vein thrombosis (DVT) in Japan, whereas fondaparinux is the standard drug in Europe and the United States. Here, we examine the efficacy and safety of fondaparinux in Japanese patients. METHODS AND RESULTS: In 2 randomized, open-label, multicenter studies, 80 Japanese patients with acute PE or DVT received either subcutaneous fondaparinux or intravenous UFH as a non-comparative reference, in a 3:1 ratio, for 5-10 days. Concomitant warfarin therapy was continued until Day 90. Multidetector-row computed tomography-based assessment showed that 57.9% and 45.9% of the patients with acute PE and acute proximal DVT had proximal DVT and PE as a complication, respectively. There was no recurrence of symptomatic venous thromboembolism. In the fondaparinux group, the respective improvement rates at the end of the initial treatment and follow-up periods were 71.4% and 86.8% for 42 patients with PE, and 57.8% and 83.3% for 46 patients with DVT; similar results were noted in the UFH group. One patient in the fondaparinux group experienced major bleeding during the initial treatment, but no such episode in the UFH group. CONCLUSIONS: Once-daily, subcutaneous fondaparinux is as effective and safe without monitoring as adjusted-dose intravenous UFH for the initial treatment of acute PE and DVT in Japanese patients.

Expression of thyroglobulin on follicular dendritic cells of thyroid mucosa-associated lymphoid tissue (MALT) lymphoma.

Reportedly, thyroid mucosa-associated lymphoid tissue (MALT) lymphoma is closely associated with Hashimoto's thyroiditis. However, it remains unknown which antigen is closely associated with thyroid MALT lymphoma. We examined whether B cell response to thyroglobulin (Tg), which is a common thyroid-specific autoantigen, is related etiologically to the pathogenesis of thyroid MALT lymphoma. Expression of human Tg antigens and Cluster of differentiation (CD) 35 was examined immunohistochemically in 15 cases of thyroid MALT lymphoma using paraffin-embedded, formalin-fixed tissue specimens. In all cases of thyroid MALT lymphoma, human Tg was detected immunohistochemically in the follicular epithelial cells and follicular dendritic cells (FDCs). These FDCs were positive by double immunostaining for anti-human Tg rabbit polyclonal antibody (Ab) and for CD35. Results showed that the Tg, a thyroid autoantigen, had immunostained the germinal center of the thyroid MALT lymphoma. The Tg was present in the FDCs, as revealed by the staining pattern of the germinal center;this fact was confirmed by double immunostaining of anti-human Tg mouse monoclonal Ab and anti-CD35 mouse monoclonal Ab. The results of our study suggest that Tg is an autoantigen that is recognized by thyroid MALT lymphoma cells.

Intravenous administration of nicorandil immediately before percutaneous coronary intervention can prevent slow coronary flow phenomenon.

AIMS: To determine the effect of intravenous administration of nicorandil on slow coronary flow (SCF) phenomenon in patients undergoing percutaneous coronary intervention (PCI). METHODS AND RESULTS: In a preliminary study, 6 mg of nicorandil showed optimal efficacy for vasodilatation without causing significant haemodynamic instability. In the main study, a total of 408 patients were randomly assigned to receive intravenous administration of 6 mg of nicorandil immediately before PCI. The number of patients in the nicorandil group was 206 [acute coronary syndrome (ACS): 47, non-ACS: 159] and that in the control group was 202 (ACS: 61, non-ACS: 141). Nicorandil significantly decreased the incidence of post-procedural SCF phenomenon in both the ACS and non-ACS groups. The rate of target vessel revascularization (TVR) was significantly lower in the nicorandil group than in the control group in ACS patients. CONCLUSION: Our simple procedure prevented SCF phenomenon not only in patients with ACS but also in patients with non-ACS without any adverse effect. Additionally our procedure reduced the rate of TVR in patients with ACS.

Morphologically unique feature of recurrent ampulla (takotsubo) cardiomyopathy.

Two similar rare cases of recurrent ampulla (takotsubo) cardiomyopathy, which was induced by physical stress of recurrent rhabdomyolysis in case 1 and aggravation of respiratory disease in case 2, are presented. At the initial admission, both patients had typical ampulla cardiomyopathy, which was indicated by transient left ventricular (LV) apical ballooning, but at the second admission, they both had atypical ampulla cardiomyopathy, as diagnosed by transient basal midventricular ballooning. Electrocardiograms at each admission showed a specific T-wave inversion, which might indicate the region of LV asynergy, and prolongation of the QT interval. In both cases, the plasma level of endogenous catecholamines was high. It is possible that excessive sympathetic stimulation induced by physical stress was the cause of this cardiomyopathy, but the cause of the differences in wall motion abnormalities between the first and second admissions was not identified. Appropriate management and treatment of the underlying disease and determining the mechanisms of recurrent ampulla cardiomyopathy might prevent its recurrence.

The ratio of the atrial areas reflects the clinical status of patients with pulmonary arterial hypertension.

PURPOSE: Echocardiography is useful not only for detecting pulmonary hypertension (PH) but also for estimating the severity of PH by evaluating various morphological changes of the heart caused by pressure and volume overload and by ventricular interaction. We investigated whether a novel echocardiographic index, i.e., the ratio of the atrial areas (RA/LA), would be useful for evaluating the clinical status of patients with pulmonary arterial hypertension (PAH) treated with intravenous epoprostenol. METHODS: We introduced epoprostenol therapy for seven PAH patients without severe tricuspid regurgitation. We evaluated clinical criteria indicative of prognosis, for example World Health Organization functional class (WHO-FC), brain natriuretic peptide (BNP) level, echocardiographic indices such as indexed RA area and RA/LA, and hemodynamics before and one year after intravenous epoprostenol therapy. RESULTS: There were significant improvements in both RA/LA (2.5 ± 1.0, 1.3 ± 0.4, P < 0.001) and indexed RA area (22.5 ± 8.9, 14.5 ± 5.8, P < 0.001). The improvement in RA/LA was more sensitive than that in indexed RA area (P < 0.01). Moreover, RA/LA was significantly correlated with WHO-FC (r = 0.50, P < 0.01) and BNP level (r = 0.82, P < 0.01). CONCLUSIONS: RA/LA is useful for evaluating the clinical status of patients with PAH treated with intravenous epoprostenol.

Additional effects of bosentan in patients with idiopathic pulmonary arterial hypertension already treated with high-dose epoprostenol.

BACKGROUND: Combination therapy has been proposed in treatment algorithms for idiopathic pulmonary arterial hypertension (IPAH), so the additional effects of bosentan in IPAH patients already treated with high-dose epoprostenol (EPO) was evaluated in the present study. METHODS AND RESULTS: Bosentan (62.5 mg twice daily) was administered to 8 IPAH patients already being treated with high-dose EPO (average dose 99.6+/-43.4 ng . kg(-1) . min(-1)). Hemodynamics were assessed at baseline and at 2 days and then 1 year after the initiation of bosentan. Because a remarkable elevation of mixed venous oxygen saturation was observed at the initiation of bosentan, the dosage of EPO was reduced in 7 patients (from 99.6+/-43.4 to 82.8+/-31.3 ng . kg(-1) . min(-1), p<0.05). There was a significant decrease from the baseline value for systolic pulmonary artery pressure (80.1+/-19.3 to 66.8+/-16.5 mmHg, p<0.05). These effects were maintained for 1 year without progression of PAH in 6 patients whose condition had been stabilized at baseline. CONCLUSIONS: The additional use of bosentan for IPAH patients whose condition has been stabilized by high-dose EPO is safe and effective.