Changes in cMRI parameters following a switch to riociguat from phosphodiesterase type 5 inhibitors (PDE5i) in patients with pulmonary arterial hypertension: a REPLACE substudy

Background

The REPLACE study investigated the effect of switching to riociguat (RIO) in patients with pulmonary arterial hypertension receiving PDE5i but still at intermediate risk. The centrally adjudicated composite primary endpoint was clinical improvement in the absence of clinical worsening, where clinical improvement was defined as meeting at least two of the following criteria: 6-minute walk distance (6MWD), increase by ≥10% or ≥30 m from baseline (BL) to Wk 24; World Health Organization functional class (WHO FC) I or II at Wk 24; or N-terminal prohormone of brain natriuretic peptide reduction of ≥30% from BL to Wk 24. Twice as many patients switching to RIO (45/111, 41%) met the primary endpoint compared with those remaining on PDE5i (23/113, 20%); odds ratio (OR): 2.78 (95% confidence interval [CI] 1.53–5.06); p=0.0007.

Purpose

Assess changes in right and left ventricular (RV; LV) function using cardiac magnetic resonance imaging (cMRI) in a subgroup of patients participating in REPLACE.

Methods

REPLACE was a randomised, open-label, 24-week, Phase 4 study (NCT02891850). Patients in WHO FC III, with 6MWD 165–440 m, were randomised to switch to RIO 2.5 mg–max tid or remain on PDE5i. Background endothelin receptor antagonist therapy was permitted in both arms.

cMRI was performed on a subset of patients from the full analysis set as an exploratory substudy. The following parameters were measured at BL and Wk 24: RV and LV end-diastolic and end-systolic volumes (RVEDV; RVESV; LVEDV; LVESV), RV stroke volume and stroke volume index (RVSV; RVSVI), LV stroke volume (LVSV), RV ejection fraction (RVEF), and pericardial effusion.

Results

Twenty-seven patients participated in the cMRI substudy. This comprised 11/111 (10%) patients in the RIO arm (mean [standard deviation {SD}] 40.0 [12.4] years), and 16/113 (14%) patients (mean 44.5 [17.6] years) in the PDE5i arm. Like the main population, the treatment response in the cMRI subpopulation favoured RIO versus PDE5i (OR: 6.11 [95% CI 0.90–41.60]). From BL to Wk 24, RVEDV and RVESV decreased in the RIO treatment arm but increased in the PDE5i treatment arm (Table 1). Similar, but less pronounced, changes were observed for the left ventricle (LVESV, LVEDV). RVSV and RVEF levels were close to normal at BL and did not increase in either arm at Wk 24 (Table 1). Pericardial effusion, which was present in 5 patients in each group at BL, decreased in 1 patient in the RIO arm and no patients in the PDE5i arm.

Conclusions

Decreases in RVEDV and RVESV suggest improvements in cardiac function in the RIO arm compared with the PDE5i arm. Values for RVEF and RVSVI were close to normal at BL and did not change at Wk 24. Improvements in cMRI parameters were in line with the clinical improvement observed in patients switching to RIO in the overall population.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): The REPLACE study was co-funded by Bayer AG (Berlin, Germany) and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (Kenilworth, NJ, USA)

Treatment effect of selexipag on time to disease progression when initiated early in pulmonary arterial hypertension (PAH) patients: GRIPHON and TRITON pooled analysis

Background

In PAH clinical practice, drugs targeting the prostacyclin pathway, including the oral prostacyclin receptor agonist selexipag, are often initiated years after diagnosis. The GRIPHON (NCT01106014) and TRITON (NCT02558231) randomised controlled trials examined the impact of selexipag on disease progression, primary and secondary endpoints, respectively. In GRIPHON, selexipag significantly reduced the risk of disease progression (composite primary endpoint) in a PAH population (N=1156) with a mean time from diagnosis of 2.4 years, as part of an oral triple, double or monotherapy regimen versus placebo. In TRITON, a potential signal for reduced risk of disease progression was observed with initial triple oral therapy (selexipag, macitentan, tadalafil) versus initial double oral therapy (placebo, macitentan, tadalafil) in a population of 247 newly diagnosed, treatment naïve patients.

Purpose

To investigate the impact of initiating selexipag within 6 months of diagnosis on disease progression in a large PAH population.

Methods

We selected patients from GRIPHON and TRITON diagnosed within 6 months of randomization and compared those on active therapy with selexipag (selexipag group) versus those on control therapy with placebo (control group). Disease progression endpoints were defined as in the GRIPHON and TRITON studies, respectively. Hazard ratios (HR) and 95% CI for time to first disease progression event up to end of double-blind treatment (selexipag/placebo) + 7 days were estimated using a Cox regression model which included treatment as a factor, and baseline prognostic factors and study as covariates.

Results

Overall, 649 patients met the criteria (diagnosis ≤6 months) for these analyses: 329 in the selexipag group (207 from GRIPHON and 122 from TRITON) and 320 in the control group (197 from GRIPHON and 123 from TRITON). Patient characteristics at baseline and treatment regimens were balanced between the treatment groups. With respect to treatment regimen, selexipag/placebo was given as part of triple therapy in 44%, double therapy in 32% and monotherapy in 24% of patients. The median (range) exposure to study treatment was 510 (4–1280) and 409 (3–1318) days in the selexipag and control groups, respectively. There were 67 (20%) and 116 (36%) patients who experienced a disease progression event in the selexipag and control groups, respectively. Selexipag reduced the risk of disease progression (first event) by 52% compared to control (HR 0.48 [95% CI 0.35, 0.66]) (Figure).

Conclusions

This post-hoc pooled analysis of GRIPHON and TRITON patients diagnosed within 6 months suggests that targeting the prostacylin pathway with selexipag within a short time after diagnosis may reduce the risk of disease progression in a broad PAH population.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Actelion Pharmaceuticals Ltd, a Janssen Pharmaceutical Company of Johnson & Johnson

Pulmonary hypertension in HFpEF and HFrEF: Pathophysiology, diagnosis, treatment approaches

Pulmonary hypertension (PH) is a frequent hemodynamic condition that is highly prevalent in patients with heart failure and reduced (HFrEF) or preserved ejection fraction (HFpEF). Irrespective of left ventricular EF, the presence of PH and right ventricular (RV) dysfunction are highly relevant for morbidity and mortality in patients with heart failure. While elevated left-sided filling pressures and functional mitral regurgitation primarily lead to post-capillary PH, current guidelines and recommendations distinguish between isolated post-capillary PH (IpcPH) and combined post- and pre-capillary PH (CpcPH), the latter being defined by a pulmonary vascular resistance (PVR) of ≥3 Wood units. Here, we describe the pathophysiology and clinical relevance of these distinct entities, and report on the diagnostic work-up including remote pulmonary artery pressure (PAP) monitoring. Furthermore, we highlight strategies to manage PH and improve RV function in heart failure, which may include optimized management of HFrEF and HFpEF (medical and interventional), sufficient volume control, catheter-based mitral valve repair, and-in selected cases-targeted PH therapy. In this context, we also highlight gaps in evidence and the need for further research.

4973Efficacy and safety of selexipag in pulmonary arterial hypertension (PAH) patients with and without significant cardiovascular (CV) comorbidities

Introduction

Many PAH patients today have a number of CV comorbidities, yet data on the efficacy and safety of therapies in such patients remain scarce. Most recent PAH clinical trials also include patients with comorbidities.

Purpose

To assess the long-term efficacy and safety of the oral, selective IP prostacyclin receptor agonist, selexipag, in PAH patients with and without significant CV comorbidities using post hoc analysis of GRIPHON data.

Methods

GRIPHON enrolled 1156 PAH patients randomised 1:1 to placebo:selexipag. The present analysis includes patients with right heart catheterisation within 1 year of randomisation who were categorised as with or without CV comorbidities. Patients with CV comorbidities were defined as having ≥3 of the following: body mass index (BMI) >30 kg/m2, history of essential hypertension, diabetes mellitus, or historical evidence of significant coronary artery disease; if PAWP/LVEDP was >12 but <15 mmHg, pulmonary vascular resistance (PVR) had to be >500 dyn.sec/cm5; if PAWP/LVEDP was <12, then PVR had to be >300 dyn.sec/cm5. Selexipag effect on time to first morbidity/mortality (M/M) event up to end of treatment was assessed for both subgroups. Baseline (BL) adjusted treatment hazard ratios with 95% CIs were calculated using Cox models. Model building involved stepwise backward elimination of BL covariates.

Results

752 PAH patients could be categorised based on these criteria (99 with CV comorbidities, 653 without). At BL, patients with CV comorbidities were older (median [range] 60 [28–80] vs 46 [18–78] yrs), had higher BMI (mean [SD] 33.3 [7.23] vs 26.0 [5.64] kg/m2) and lower 6-minute walk distance (mean [SD] 319 [95.7] vs 354 [79.3] m) vs those without. A greater proportion were from Western Europe/Australia/North America (60.6% vs 38.9%) and in WHO functional class III (69.7% vs 49.9%). At BL, 82.8% of patients with CV comorbidities were receiving PAH therapies vs 75.7% of those without. As expected, at BL a higher proportion of patients with CV comorbidities (vs without) had previous/concomitant cardiac disease (62.6% vs 43.0%), metabolism/nutrition disorders (75.8% vs 31.2%), respiratory/thoracic/mediastinal disorders (59.6% vs 37.5%) and vascular disorders (76.8% vs 37.4%). Selexipag reduced the risk of M/M events vs placebo in both subgroups (Figure), with no evidence of an inconsistent treatment effect (interaction p-value=0.1544). Adverse events leading to treatment discontinuation were reported in 35.4% (25.9% selexipag, 46.7% placebo) of patients with CV comorbidities and 35.0% (32.0% selexipag, 38.0% placebo) of those without. Common prostacyclin associated side effects observed with selexipag (headache, diarrhoea, nausea) were reported at a similar incidence in both subgroups.

Conclusions

Selexipag had a beneficial effect on long-term outcome in PAH patients both with and without CV comorbidities. Safety in both groups was consistent with the known profile of selexipag.

Acknowledgement/Funding

Actelion Pharmaceuticals Ltd

Evaluation of a newly developed 2D parametric parenchymal blood flow technique with an automated vessel suppression algorithm in patients with chronic thromboembolic pulmonary hypertension undergoing balloon pulmonary angioplasty

AIM

To evaluate the feasibility of two-dimensional parametric parenchymal blood flow (2D-PPBF) to quantify perfusion changes in the lung parenchyma following balloon pulmonary angioplasty (BPA) for treatment of chronic thromboembolic pulmonary hypertension.

MATERIALS AND METHODS

Overall, 35 consecutive interventions in 18 patients with 98 treated pulmonary arteries were included. To quantify changes in pulmonary blood flow using 2D-PPBF, the acquired digital subtraction angiography (DSA) series were post-processed using dedicated software. A reference region of interest (ROI; arterial inflow) in the treated pulmonary artery and a distal target ROI, including the whole lung parenchyma distal to the targeted stenosis, were placed in corresponding areas on DSA pre- and post-BPA. Half-peak density (HPD), wash-in rate (WIR), arrival to peak (AP), area under the curve (AUC), and mean transit time (MTT) were assessed. The ratios of the reference ROI to the target ROI (HPD_parenchyma/HPD_inflow, WIR_parenchyma/WIR_inflow; AP_parenchyma/AP_inflow, AUC_parenchyma/AUC_inflow, MTT_parenchyma/MTT_inflow) were calculated. The relative differences of the 2D-PPBF parameters were correlated to changes in the pulmonary flow grade score.

RESULTS

The pulmonary flow grade score improved significantly after BPA (1 versus 3; p<0.0001). Likewise, the mean HPD_parenchyma/HPD_inflow (-10.2%; p<0.0001), AP_parenchyma/AP_inflow (-24.4%; p=0.0007), and MTT_parenchyma/MTT_inflow (-3.5%; p=0.0449) decreased significantly, whereas WIR_parenchyma/WIR_inflow (+82.4%) and AUC_parenchyma/AUC_inflow (+58.6%) showed a significant increase (p<0.0001). Furthermore, a significant correlation between changes of the pulmonary flow grade score and changes of HPD_parenchyma/HPD_inflow (ρ=-0.21, p=0.04), WIR_parenchyma/WIR_inflow (ρ=0.43, p<0.0001), AP_parenchyma/AP_inflow (ρ=-0.22, p=0.03), AUC_parenchyma/AUC_inflow (ρ=0.48, p<0.0001), and MTT_parenchyma/MTT_inflow (ρ=-0.39, p<0.0001) could be observed.

CONCLUSION

The 2D-PPBF technique is feasible for the quantification of perfusion changes following BPA and has the potential to improve monitoring of BPA.

[Risk stratification and follow-up assessment of patients with pulmonary arterial hypertension: Recommendations of the Cologne Consensus Conference 2016]

The 2015 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension are also valid for Germany. The guidelines contain detailed information about the diagnosis of pulmonary hypertension, and furthermore provide novel recommendations for risk stratification and follow-up assessments. However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to risk stratification and follow-up assessment of patients with PAH. This manuscript summarizes the results and recommendations of this working group.

[Chronic thromboembolic pulmonary hypertension: Recommendations of the Cologne Consensus Conference 2016]

The 2015 European Guidelines on Pulmonary Hypertension did not cover only pulmonary arterial hypertension (PAH), but also other significant subgroups of pulmonary hypertension (PH). In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany to discuss open and controversial issues surrounding the practical implementation of the European Guidelines. Several working groups were initiated, one of which was dedicated to the diagnosis and treatment of chronic thromboembolic pulmonary hypertension (CTEPH). In every patient with PH of unknown cause CTEPH should be excluded. The primary treatment option is surgical pulmonary endarterectomy (PEA) in a specialized multidisciplinary CTEPH center. Inoperable patients or patients with persistent or recurrent CTEPH after PEA are candidates for targeted drug therapy. For balloon pulmonary angioplasty (BPA), there is currently only limited experience. This option - as PEA - is reserved to specialized centers with expertise for this treatment method. In addition, a brief overview is given on pulmonary artery sarcoma, since its surgical treatment is often analogous to PEA. The recommendations of this working group are summarized in the present paper.

[Targeted therapy of pulmonary arterial hypertension: Recommendations of the Cologne Consensus Conference 2016]

The 2015 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension are also valid for Germany. The guidelines contain detailed recommendations for the targeted treatment of pulmonary arterial hypertension (PAH). However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the targeted therapy of PAH. This article summarizes the results and recommendations of the working group on targeted treatment of PAH.

[Decompensated right heart failure, intensive care and perioperative management in patients with pulmonary hypertension]

The 2015 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension are also valid for Germany. The guidelines contain detailed recommendations for the targeted treatment of pulmonary arterial hypertension (PAH). However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the management of decompensated right heart failure, intensive care management and perioperative management in patients with pulmonary hypertension. This article summarizes the results and recommendations of the working group on decompensated right heart failure, intensive care and perioperative management in patients with pulmonary hypertension.

Prolonged Mechanical Ventilation After Lung Transplantation-A Single-Center Study

This single-center study examines the incidence, etiology, and outcomes associated with prolonged mechanical ventilation (PMV), defined as time to definite spontaneous ventilation >21 days after double lung transplantation (LTx). A total of 690 LTx recipients between January 2005 and December 2012 were analyzed. PMV was necessary in 95 (13.8%) patients with decreasing incidence during the observation period (p < 0.001). Independent predictors of PMV were renal replacement therapy (odds ratio [OR] 11.13 [95% CI, 5.82-21.29], p < 0.001), anastomotic dehiscence (OR 8.74 [95% CI 2.42-31.58], p = 0.001), autoimmune comorbidity (OR 5.52 [95% CI 1.86-16.41], p = 0.002), and postoperative neurologic complications (OR 5.03 [95% CI 1.98-12.81], p = 0.001), among others. Overall 1-year survival was 86.0% (90.4% for LTx between 2010 and 2012); it was 60.7% after PMV and 90.0% in controls (p < 0.001). Conditional long-term outcome among hospital survivors, however, did not differ between the groups (p = 0.78). Multivariate analysis identified renal replacement therapy (hazard ratio [HR] 3.55 [95% CI 2.40-5.25], p < 0.001), post-LTx extracorporeal membrane oxygenation (HR 3.47 [95% CI 2.06-5.83], p < 0.001), and prolonged inotropic support (HR 1.95 [95% CI 1.39-2.75], p < 0.001), among others, as independent predictors of mortality. In conclusion, PMV complicated 14% of LTx procedures and, although associated with increased in-hospital mortality, outcomes among patients surviving to hospital discharge were unaffected.

[Plasma exchange in treatment refractory septic shock : Presentation of a therapeutic add-on strategy]

Sepsis is defined as a systemic inflammatory response of the body to an infection. Besides anti-infective drugs and removal of the site of infection, no specific therapeutics that target the overwhelming host response are available. Clinical researchers are currently evaluating the extracorporeal elimination of circulating cytokines. Modern adsorbing techniques have increasingly been used for this purpose allowing an unselective but highly effective removal of the vast majority of circulating cytokines but also fail to replace used protective factors in patients' plasma. Therapeutic plasma exchange (TPE) however might represent a novel method to remove pathologically elevated cytokines and simultaneously to replace protective plasmatic factors. Here we report the case of a septic shock patient treated with TPE and review the available literature with respect to TPE as an adjunctive therapy in sepsis.

[Riociguat: stimulator of soluble guanylate-cyclase. New mode of action for the treatment of pulmonary arterial and non operable chronic thromboembolic pulmonary hypertension]

Riociguat is the first clinically available soluble Guanylate-cyclase stimulator (sGC) and representative of a completely new class of drugs. Riociguat is approved for pulmonary arterial hypertension (PAH) and non-operable or recurrent/persistent chronic thromboembolic pulmonary hypertension (CTEPH). Moreover, Riociguat is currently under investigation for a wider spectrum of diseases. This article focusses on its mode of action and clinical trial data. Finally, based on these data, the status of approval, as well as the costs a proposal is given how Riociguat can be integrated in the current treatment of PAH and CTEPH.

[Characteristics and management of idiopathic pulmonary fibrosis: INSIGHTS-IPF registry]

Idiopathic pulmonary fibrosis (IPF), a manifestation of chronic progressive fibrosing interstitial pneumonia, is with a prevalence of 2-29 cases per 100,000 individuals a rare disease. Current treatment options are limited, and the mean survival time of the newly diagnosed (mostly elderly) patients is only about 2-3 years. As in Europe data are limited on the characteristics and management of such patients, INSIGHTS-IPF was initiated as a new registry that documents incident and prevalent patients with confirmed IPF diagnosis prospectively. Detailed data on patient characteristics, diagnostics, management, clinical outcomes, quality of life and resource utilization are recorded. It is planned to document 500 patients in 30 centers. The registry will contribute to the optimization of the management of IPF patients in the long term.

[Right heart failure in chronic pulmonary hypertension and acute pulmonary embolism]

Right-sided heart failure is a severe and often life-threatening complication of chronic pulmonary hypertension. The detection of trigger factors that induce right heart failure in previously stable patients is important to initiate a causal therapeutic strategy. Pulmonary embolism (PE) is a frequent cause of acute right heart failure and therapeutic strategies for PE are well documented in the current guidelines. Treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH) is surgical pulmonary endarterectomy (PEA) and patients with possible CTEPH should be referred to an experienced PEA surgeon without delay. Intensive care management for overt right heart failure is complex and includes the use of pulmonary vasodilators, individual adjustment of diuretic or volume therapy, augmentation of myocardial contractility and left ventricular afterload. Therapeutic regimens aim at optimized filling of the right ventricle, improvement of myocardial perfusion by avoiding tachycardia, elevating systemic pressure and reducing right ventricular afterload. Early communication with a specialized center for pulmonary hypertension is recommended.

The prognostic impact of follow-up assessments in patients with idiopathic pulmonary arterial hypertension

Current guidelines for the treatment of patients with idiopathic pulmonary arterial hypertension (IPAH) recommend basing therapeutic decision-making on haemodynamic, functional and biochemical variables. Most of these parameters have been evaluated as risk predictors at the time of diagnosis. The aim of the present study was to assess the prognostic impact of changes in these parameters after initiation of targeted therapy. A cohort of 109 patients with IPAH who had undergone haemodynamic, functional and biochemical assessments at baseline and 3-12 months after initiation of pulmonary arterial hypertension (PAH)-targeted therapy, were followed for a median 38 months in order to determine predictors of mortality at baseline and during the course of their disease. Within the observation period, 53 (48.6%) patients died and four (3.7%) underwent lung transplantation. Kaplan-Meier estimates for transplantation-free survival were 92%, 67%, and 51% at 1, 3, and 5 yrs, respectively. Among baseline variables, 6-min walk distance, right atrial pressure, cardiac index, mixed-venous oxygen saturation (S(v,O(2))) and N-terminal-pro brain natriuretic peptide (NT-proBNP) were independent predictors of survival. During follow-up, changes in World Health Organization functional class, cardiac index, S(v,O(2)) and NT-proBNP proved significant predictors of outcome. When assigned to prognostic groups, improvements as well as deteriorations in these parameters after initiation of PAH-targeted therapy had a strong impact on survival. Measurements obtained at follow-up had a higher predictive value than variables obtained at baseline. Changes in established predictors of outcome during the course of the disease provide important prognostic information in patients with IPAH.

[Chronic thromboembolic pulmonary hypertension: recommendations of the Cologne Consensus Conference 2010]

In the 2009 European Guidelines on pulmonary hypertension one section covers aspects of pathophysiology, diagnosis and treatment of chronic thromboembolic pulmonary hypertension (CTEPH). The practical implementation of the guidelines for this disease is of crucial importance, because CTEPH is a form of pulmonary hypertension which can be surgically cured. It is, however, frequently diagnosed late in the course of disease and often treated not correctly. In the European Guidelines CTEPH is addressed relatively briefly, although it is a common form of PH which is often overlooked. Any patient with unexplained PH should be evaluated for the presence of CTEPH. A ventilation/perfusion lung scan is recommended as the first step to exclude CTEPH. If the ventilation/perfusion lung scan or multislice CT angiography reveals perfusions defects suggesting the diagnosis of CTEPH, the patient should be referred to a centre with expertise in the medical and surgical management of these patients. After diagnosis of CTEPH the case has to be reviewed by an experienced surgeon in a PEA centre for assessment of operability. The recommendations of the European guidelines are summarized in the current manuscript with additional comments regarding diagnosis and treatment according to most recent evidence.

[Pulmonary hypertension due to chronic lung disease. Recommendations of the Cologne Consensus Conference 2010]

The 2009 European Guidelines on Pulmonary Hypertension did not cover only pulmonary arterial hypertension (PAH) but also some aspects of pulmonary hypertension (PH) in chronic lung disease. The European Guidelines point out that the drugs currently used to treat patients with PAH (prostanoids, endothelin receptor antagonists and phosphodiesterase-5 inhibitors) have not been sufficiently investigated in other forms of PH. Therefore, the European Guidelines do not recommend the use of these drugs in patients with chronic lung disease and PH. This recommendation, however, is not always in agreement with medical ethics as physicians feel sometimes inclined to treat other form of pulmonary hypertension which may affect quality of life and survival of these patients in a similar manner. In June 2010, a group of German experts met in Cologne, Germany, to discuss open and controversial issues surrounding the practical implementation of the European Guidelines. The conference was sponsored by the German Society of Cardiology, the German Society of Respiratory Medicine and the German Society of Pediatric Cardiology. One of the working groups was dedicated to the diagnosis and treatment of PH in patients with chronic lung disease. The recommendations of this working group are summarized in the present paper.

Extracorporeal membrane oxygenation in nonintubated patients as bridge to lung transplantation

We report on the use of veno-arterial extracorporeal membrane oxygenation (ECMO) as a bridging strategy to lung transplantation in awake and spontaneously breathing patients. All five patients described in this series presented with cardiopulmonary failure due to pulmonary hypertension with or without concomitant lung disease. ECMO insertion was performed under local anesthesia without sedation and resulted in immediate stabilization of hemodynamics and gas exchange as well as recovery from secondary organ dysfunction. Two patients later required endotracheal intubation because of bleeding complications and both of them eventually died. The other three patients remained awake on ECMO support for 18-35 days until the time of transplantation. These patients were able to breathe spontaneously, to eat and drink, and they received passive and active physiotherapy as well as psychological support. All of them made a full recovery after transplantation, which demonstrates the feasibility of using ECMO support in nonintubated patients with cardiopulmonary failure as a bridging strategy to lung transplantation.

Riociguat for chronic thromboembolic pulmonary hypertension and pulmonary arterial hypertension: a phase II study

We assessed the therapeutic potential of riociguat, a novel soluble guanylate cyclase stimulator, in adults with chronic thromboembolic pulmonary hypertension (CTEPH; n = 42) or pulmonary arterial hypertension (PAH; n = 33) in World Health Organization (WHO) functional class II/III. In this 12-week, multicentre, open-label, uncontrolled phase II study, patients received oral riociguat 1.0-2.5 mg t.i.d. titrated according to systemic systolic blood pressure (SBP). Primary end-points were safety and tolerability; pharmacodynamic changes were secondary end-points. Riociguat was generally well tolerated. Asymptomatic hypotension (SBP <90 mmHg) occurred in 11 patients, but blood pressure normalised without dose alteration in nine and after dose reduction in two. Median 6-min walking distance increased in patients with CTEPH (55.0 m from baseline (390 m); p<0.0001) and PAH (57.0 m from baseline (337 m); p<0.0001); patients in functional class II or III and bosentan pre-treated patients showed similar improvements. Pulmonary vascular resistance was significantly reduced by 215 dyn·s·cm(-5) from baseline (709 dyn·s·cm(-5); p<0.0001). 42 (56%) patients were considered to have experienced drug-related adverse events (AEs; 96% mild or moderate). Dyspepsia, headache and hypotension were the most frequent AEs. Study discontinuation because of AEs was 4%. These preliminary data show that riociguat has a favourable safety profile and improves exercise capacity, symptoms and pulmonary haemodynamics in CTEPH and PAH. Randomised controlled trials are underway.