Chemotherapy Improved Pulmonary Arterial Hypertension in a Patient with Chronic-Active Epstein-Barr Virus Infection.

Chronic-active Epstein-Barr virus infection (CAEBV) is a rare disease that can lead to pulmonary arterial hypertension (PAH). However, the treatment for CAEBV-associated PAH has not been established. We discuss a case of improved pulmonary hypertension after chemotherapy in a patient with CAEBV-associated PAH. A 44-year old man was admitted to our hospital because of an abnormal electrocardiogram and liver dysfunction detected by annual medical examination. Echocardiography showed a dilated right ventricle and an estimated right ventricular systolic pressure of 92 mmHg. Right heart catheterization revealed a mean pulmonary arterial pressure of 45 mmHg and pulmonary vascular resistance of 9.8 Wood units. Laboratory examination showed granular lymphocytes and 91% natural killer cells in lymphocyte subsets in peripheral blood. We diagnosed the patient as having CAEBV-associated PAH. After two cycles of chemotherapy without PAH-specific drugs, echocardiography showed improvement in the dilated right ventricle and an estimated right ventricular systolic pressure of 59 mmHg. Right heart catheterization revealed a mean pulmonary arterial pressure of 27 mmHg and pulmonary vascular resistance of 2.4 Wood units. Chemotherapy may improve pulmonary hypertension in patients with CAEBV-associated PAH.

Successful Transition From Phosphodiesterase-5 Inhibitors to Riociguat Without a Washout Period in Patients With Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension: A Pilot Cohort Study.

BACKGROUND: Transition to pulmonary arterial hypertension (PAH)-specific drugs is considered in patients with PAH and chronic thromboembolic pulmonary hypertension who do not respond to combination therapy or who experience side effects to the combination drugs. Riociguat directly stimulates soluble guanylate cyclase independently of nitric oxide. Therefore, transition from a phosphodiesterase type 5 inhibitor (PDE5i), which requires nitric oxide to exert its effects, to riociguat might be effective. The length of time of washout periods for transition is important because haemodynamic instability sometimes occurs during these periods or during transition with no washout period. METHOD: We investigated the feasibility of transitioning from a PDE5i to riociguat without washout periods by monitoring haemodynamics under right heart catheterisation in six patients with PAH and one with chronic thromboembolic pulmonary hypertension who had already received dual- or triple-combination therapy. RESULTS: Reasons for transition were headache caused by a PDE5i in three patients, and an inadequate response to combination therapy in four. Transition was successful in all patients, with no haemodynamic instability observed. Pulmonary vascular resistance (from 797 ± 241 to 518 ± 230 dyne/s/cm-5) and systemic blood pressure (from 121 ± 13 to 100 ± 15 mmHg) were significantly reduced immediately after transition. There were no significant differences in the tricuspid regurgitation pressure gradient or systemic blood pressure during the post-transition and follow-up periods. Headaches caused by a PDE5i were diminished after transition to riociguat. CONCLUSIONS: Transition from a PDE5i to riociguat without a washout period is safe. This transition may be a viable option for patients with headaches caused by a PDE5i, or who have an inadequate response to combination therapy that includes a PDE5i.

Crucial role of RAGE in inappropriate increase of smooth muscle cells from patients with pulmonary arterial hypertension.

BACKGROUND: Pulmonary vascular remodeling of pulmonary arterial hypertension (PAH) is characterized by an inappropriate increase of vascular cells. The receptor for advanced glycation end products (RAGE) is a type I single-pass transmembrane protein belonging to the immunoglobulin superfamily and is involved in a broad range of hyperproliferative diseases. RAGE is also implicated in the etiology of PAH and is overexpressed in pulmonary artery smooth muscle cells (PASMCs) in patients with PAH. We examined the role of RAGE in the inappropriate increase of PASMCs in patients with PAH. METHODS AND RESULTS: PASMCs were obtained from 12 patients with PAH including 9 patients with idiopathic PAH (IPAH) and 3 patients with heritable PAH (HPAH) (2 patients with BMPR2 mutation and one patient with SMAD9 mutation) who underwent lung transplantation. Western blot analysis and immunofluorescence staining revealed that RAGE and S100A8 and A9, ligands of RAGE, were overexpressed in IPAH and HPAH-PASMCs in the absence of any external growth stimulus. PDGF-BB (10 ng/mL) up-regulated the expression of RAGE in IPAH and HPAH-PASMCs. PAH-PASMCs are hyperplastic in the absence of any external growth stimulus as assessed by 3H-thymidine incorporation. This result indicates overgrowth characterized by continued growth under a condition of no growth stimulation in PAH-PASMCs. PDGF-BB stimulation caused a higher growth rate of PAH-PASMCs than that of non-PAH-PASMCs. AS-1, an inhibitor of TIR domain-mediated RAGE signaling, significantly inhibited overgrowth characterized by continued growth under a condition of no growth stimulation in IPAH and HPAH-PASMCs (P<0.0001). Furthermore, AS-1 significantly inhibited PDGF-stimulated proliferation of IPAH and HPAH-PASMCs (P<0.0001). CONCLUSIONS: RAGE plays a crucial role in the inappropriate increase of PAH-PASMCs. Inhibition of RAGE signaling may be a new therapeutic strategy for PAH.

Progression of pulmonary artery dilatation in patients with pulmonary hypertension coexisting with a pulmonary artery aneurysm.

BACKGROUND: Pulmonary artery (PA) dilatation is usually observed in patients with pulmonary hypertension (PH), but a PA aneurysm (PA diameter > 40mm) is rare. The difference between characteristics of patients with and those without progression of PA diameter remains poorly understood. We assessed the changes in PA diameter in patients with PH coexisting with and without a PA aneurysm. METHODS: We investigated the changes in PA diameter by multi-detector computed tomography performed twice with an interval of more than one year in 44 patients with PH. Seventeen patients had a PA aneurysm and 27 patients did not have a PA aneurysm at baseline. RESULTS: The median follow-up period was 3.6 years. All patients received medical or invasive treatment for PH. At baseline, main PA diameters were 52±15mm in patients with a PA aneurysm and 33±3mm in patients without a PA aneurysm. Mean PA pressure was higher in patients with a PA aneurysm than in those without a PA aneurysm (61±15mmHg vs. 51±16mmHg, p=0.04). At follow-up, mean PA pressure significantly decreased in both patients with a PA aneurysm (44±11mmHg) and patients without a PA aneurysm (41±18mmHg). Main PA diameter significantly increased in patients with a PA aneurysm (65±28mm, change ratio: 23.3%), while it did not increase in patients without a PA aneurysm (32±3mm, change ratio: -3.1%). CONCLUSIONS: PA dilatation progressed in patients with a PA aneurysm despite treatment of PH. The progression of PA dilatation is independent of reduction of PA pressure by PH treatment.

Treat-and-repair strategy is a feasible therapeutic choice in adult patients with severe pulmonary arterial hypertension associated with a ventricular septal defect: case series.

INTRODUCTION: Recent advances in pulmonary arterial hypertension (PAH)-specific drugs have dramatically changed the therapeutic strategy for PAH. A strategy that includes 'treatment' with PAH-specific drugs initially and then 'repair' by closure of the cardiac defect (i.e. 'treat and repair') was devised, and has been attempted, in patients with PAH associated with a cardiac defect. CASE PRESENTATION: We present three cases of severe PAH associated with a ventricular septal defect (VSD) in adult patients who were initially treated with PAH-specific drugs followed by VSD closure. Two of the patients were treated with a combination of an endothelin receptor antagonist (ERA), phosphodiesterase type 5 inhibitor, and intravenous prostacyclin before VSD closure. The third patient was treated with an ERA and pulmonary artery banding before VSD closure. After 12 months of anti-PAH treatment, the pulmonary vascular resistance index and the ratio of the pulmonary vascular index to the systemic vascular resistance index decreased to levels that allowed VSD closure. At the mid- and long-term follow-up measurements after surgical closure of the VSD, the mean pulmonary artery pressure had markedly decreased. DISCUSSION: Our case series suggests that the treat-and-repair strategy is a promising approach for adult patients with severe PAH associated with VSD.

Suppression of Wnt Signaling and Osteogenic Changes in Vascular Smooth Muscle Cells by Eicosapentaenoic Acid.

Vascular medial calcification is often observed in patients with arteriosclerosis. It is also associated with systolic hypertension, wide pulse pressure, and fluctuation of blood pressure, which results in cardiovascular events. Eicosapentaenoic acid (EPA) has been shown to suppress vascular calcification in previous animal experiments. We investigated the inhibitory effects of EPA on Wnt signaling, which is one of the important signaling pathways involved in vascular calcification. Intake of food containing 5% EPA resulted in upregulation of the mRNA expression of Klotho, an intrinsic inhibitor of Wnt signaling, in the kidneys of wild-type mice. Expression levels of ß-catenin, an intracellular signal transducer in the Wnt signaling pathway, were increased in the aortas of Klotho mutant (kl/kl) mice compared to the levels in the aortas of wild-type mice. Wnt3a or BIO, a GSK-3 inhibitor that activates ß-catenin signaling, upregulated mRNA levels of AXIN2 and LEF1, Wnt signaling marker genes, and RUNX2 and BMP4, early osteogenic genes, in human aorta smooth muscle cells. EPA suppressed the upregulation of AXIN2 and BMP4. The effect of EPA was cancelled by T0070907, a PPARγ inhibitor. The results suggested that EPA could suppress vascular calcification via the inhibition of Wnt signaling in osteogenic vascular smooth muscle cells via PPARγ activation.

High Frequency of Acute Adverse Cardiovascular Events After Lung Transplantation in Patients With Pulmonary Arterial Hypertension Receiving Preoperative Long-Term Intravenous Prostacyclin.

Adverse cardiovascular events after lung transplantation (LT) increase the mortality in patients with pulmonary arterial hypertension (PAH). Long-term intravenous prostacyclin is the usual treatment in severe patients with PAH, but it may increase the risk of hemorrhage due to its antiplatelet aggregation effect or thrombocytopenia. We investigated the impact of length of intravenous prostacyclin therapy on acute adverse cardiovascular events including hemorrhagic complication after LT. We retrospectively compared the incidence of adverse events (death, intrathoracic hematoma and bleeding, cardiac congestion or shock, cerebral infarction and pulmonary embolism) within 30 days after LT between no/short-term (median 0.6 years, n = 13) and long-term (median 3.7 years, n = 15) intravenous prostacyclin groups. There were no differences in the dose of intravenous prostacyclin and pulmonary artery pressure between the two groups. Among 22 adverse events (0.8 ± 1.1 events/patient), 4 events occurred in the no/short-term intravenous prostacyclin group and 18 occurred in the long-term intravenous prostacyclin group. The event rate per patient in the long-term intravenous prostacyclin group (1.2 ± 1.3 events/patient) was significantly higher than that in the no/short-term intravenous prostacyclin group (0.3 ± 0.5 events/patient) (P < 0.05). Intrathoracic hematoma and bleeding was the most frequent adverse event (9 events, 41%). Preoperative long-term intravenous prostacyclin therapy increases acute adverse cardiovascular events after LT in patients with PAH.

Nanoparticle-Mediated Drug Delivery System for Pulmonary Arterial Hypertension.

Nanoparticles have been used as a novel drug delivery system. Drug-incorporated nanoparticles for local delivery might optimize the efficacy and minimize the side effects of drugs. The efficacy and safety of intratracheal administration of prostacyclin analog (beraprost) -incorporated nanoparticles and imatinib (a PDGF-receptor tyrosine kinase inhibitor) -incorporated nanoparticles in Sugen-hypoxia-normoxia or monocrotaline rat models of pulmonary arterial hypertension (PAH) and in human PAH-pulmonary arterial smooth muscle cells have been reported. The use of inhaled drug-incorporated nanoparticles might be a novel approach for the treatment of PAH.

Reverse Right Ventricular Remodeling After Lung Transplantation in Patients With Pulmonary Arterial Hypertension Under Combination Therapy of Targeted Medical Drugs.

BACKGROUND: Patients with pulmonary arterial hypertension (PAH) are currently treated with combination therapy of PAH-targeted drugs. Reverse right ventricular (RV) remodeling after lung transplantation (LTx) in patients with end-stage PAH despite combination therapy of PAH-targeted drugs has not been fully elucidated.Methods and Results:A total of 136 patients, including 32 with PAH, underwent LTx from 1998 to 2014. We enrolled 12 consecutive patients with PAH treated with combination therapy of PAH-targeted drugs who underwent LTx and retrospectively analyzed the temporal and serial changes in hemodynamics and echocardiography before LTx and at 3 and 12 months after LTx. Before LTx, the RV was markedly dilated with substantially reduced RV fractional area change (RVFAC). At 3 months after LTx, pulmonary artery pressure, pulmonary vascular resistance and RV stroke work index were significantly decreased, while left ventricular stroke work index was increased. RV size assessed by echocardiography also significantly decreased and RVFAC improved. At 12 months after LTx, RVFAC was further increased and RV wall thickness was decreased significantly. CONCLUSIONS: Although severe RV dysfunction and dilation were observed in patients with end-stage PAH despite combination therapy of PAH-targeted drugs, RV function and morphology were improved after reduction of RV pressure load by LTx.

Feasibility of Repairing Defects Followed by Treatment with Pulmonary Hypertension-specific Drugs (Repair and Treat) in Patients with Pulmonary Hypertension Associated with Atrial Septal Defect: Study Protocol for Interventional Trial.

A treatment strategy for patients with pulmonary hypertension (PH) and atrial septal defect (ASD) remains unclear. This study was designed to evaluate the effects of initial repair of ASD followed by treatment with PH-specific drugs in patients with PH and ASD. Eligible patients receive transcatheter ASD closure followed by treatment with bosentan and sildenafil. Right heart catheterization is performed at baseline and at 12, 24 and 48 weeks. The primary endpoint is change in pulmonary artery pressure and pulmonary vascular resistance from baseline to follow-up. This study should provide valuable information to establish a therapeutic strategy for PH and ASD.

Epoprostenol Therapy for Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is characterized by elevation of pulmonary artery pressure caused by pulmonary vasoconstriction and vascular remodeling, which leads to right heart failure and death. Epoprostenol (prostaglandin I2) has a potent short-acting vasodilator property, and intravenous continuous epoprostenol is therefore used for treatment of PAH. Here we review evidence for the usefulness of intravenous continuous epoprostenol therapy in patients with PAH. Epoprostenol therapy is effective in idiopathic PAH patients and in patients with PAH associated with connective tissue disease, portal hypertension or congenital heart diseases, but it is not effective in patients with pulmonary veno-occlusive disease or pulmonary capillary hemangiomatosis. High-dose epoprostenol therapy markedly improved hemodynamics in some patients with PAH, possibly due to reverse remodeling of pulmonary arteries. This therapy has several side effects and complications such as headache, hypotension and catheter-related infections. Intravenous continuous epoprostenol is an effective treatment, but there are still some problems to be resolved.

Epoprostenol sodium for treatment of pulmonary arterial hypertension.

The release of endogenous prostacyclin (PGI2) is depressed in patients with pulmonary arterial hypertension (PAH). PGI2 replacement therapy by epoprostenol infusion is one of the best treatments available for PAH. Here, we provide an overview of the current clinical data for epoprostenol. Epoprostenol treatment improves symptoms, exercise capacity, and hemodynamics, and is the only treatment that has been shown to reduce mortality in patients with idiopathic PAH (IPAH) in randomized clinical trials. We have reported that high-dose epoprostenol therapy (>40 ng/kg/min) also results in marked hemodynamic improvement in some patients with IPAH. High-dose epoprostenol has a pro-apoptotic effect on PAH-PASMCs via the IP receptor and upregulation of Fas ligand (FasL) in vitro. However, long-term intravenous administration of epoprostenol is sometimes associated with catheter-related infections and leads to considerable inconvenience for the patient. In the future, the development of new routes of administration or the development of powerful PGI2 analogs, IP-receptor agonists, and gene and cell-based therapy enhancing PGI2 production with new routes of administration is required.