The echocardiographic course of pretransplant pulmonary hypertension following kidney transplantation and associated outcomes

The post 3 kidney transplant course of pretransplant echocardiographically‐defined pulmonary hypertension (PH) was reviewed in 115 patients. Of these 61 patients (the largest cohort reported to date), underwent 160 “for indication” echocardiograms posttransplant (mean echocardiograms per patient: 2.6 ± 2.3). Patients undergoing posttransplant echocardiograms demonstrated greater risks for worse outcomes than those without posttransplant echocardiograms; however, there was no difference in mortality, death‐censored graft failure or the composite of death or graft failure between these two groups. Of patients tested, 36 (59%) showed resolution of PH at a median of 37.5 months. Six patients (16.7%) in whom PH resolved (at a median of 29 months), experienced recurrence of PH after an interval of 48 months. No pretransplant demographic or echocardiographic characteristics distinguished those in whom PH persisted versus resolved. Though there was no difference in the risk for mortality or death‐censored graft loss between the two groups at 3 and 5 years, there was a higher risk for the composite of mortality or graft loss at three but not at five years in the group with persistent PH. In conclusion, echocardiographically defined PH resolved in 59% of patients following kidney transplantation; but irrespective of resolution there was no clear association with worse outcome.

Change in REVEAL Lite 2 risk score predicts outcomes in patients with pulmonary arterial hypertension in the PATENT study

BACKGROUND

Risk assessment is essential in pulmonary arterial hypertension (PAH) management. We investigated the effect of riociguat on REVEAL Lite 2 score, an abridged version of the REVEAL risk score, and its association with long-term outcomes in PATENT.

METHODS

PATENT-1 was a randomized, double-blind study of riociguat vs placebo in patients with PAH. In the PATENT-2 open-label extension, all patients received riociguat up to 2.5 mg three times daily (n = 396). REVEAL Lite 2 scores were calculated at baseline, PATENT-1 Week 12, and PATENT-2 Week 12, with patients stratified as low- (1-5), intermediate- (6-7), or high-risk (≥8). Kaplan-Meier and Cox proportional hazards analyses assessed association of riociguat with survival and clinical worsening-free survival (CWFS).

RESULTS

REVEAL Lite 2 score improved with riociguat 2.5 mg at PATENT-1 Week 12 (least-squares mean difference vs placebo: -0.8; p = 0.0004). More patients receiving riociguat 2.5 mg stabilized or improved risk stratum at PATENT-1 Week 12 vs placebo (p = 0.0005) and achieved low-risk status. REVEAL Lite 2 score at baseline and PATENT-1 Week 12 were associated with survival and CWFS (all p < 0.0001), as was change in score from baseline to Week 12 (p = 0.0002 and p < 0.0001, respectively). Survival and CWFS differed between risk strata at baseline (p < 0.0001) and PATENT-1 Week 12 (p < 0.0001).

CONCLUSIONS

This analysis confirms the risk-reduction benefits of riociguat in patients with PAH and further contributes to the validation of REVEAL Lite 2 in facilitating PAH risk assessment.

Optimization of Acute Kidney Injury (AKI) Time Definitions Using the Electronic Health Record: A First Step in Automating In-Hospital AKI Detection

Kidney Disease: Improving Global Outcomes (KDIGO) acute kidney injury (AKI) definitions were evaluated for cases detected and their respective outcomes using expanded time windows to 168 h. AKI incidence and outcomes with expanded time intervals were identified in the electronic health records (EHRs) from 126,367 unique adult hospital admissions (2012-2014) and evaluated using multivariable logistic regression with bootstrap sampling. The incidence of AKI detected was 7.4% (n = 9357) using a 24-h time window for both serum creatinine (SCr) criterion 1a (≥0.30 mg/dL) and 1b (≥50%) increases from index SCr, with additional cases of AKI identified: 6963 from 24-48 h.; 2509 for criterion 1b from 48 h to 7 days; 3004 cases (expansion of criterion 1a and 1b from 48 to 168 h). Compared to patients without AKI, adjusted hospital days increased if AKI (criterion 1a and 1b) was observed using a 24-h observation window (5.5 days), 48-h expansion (3.4 days), 48-h to 7-day expansion (6.5 days), and 168-h expansion (3.9 days); all are p < 0.001. Similarly, the adjusted risk of in-hospital death increased if AKI was detected using a 24-h observation window (odds ratio (OR) = 16.9), 48-h expansion (OR = 5.5), 48-h to 7-day expansion (OR = 4.2), and 168-h expansion (OR = 1.6); all are p ≤ 0.01. Expanding the time windows for both AKI SCr criteria 1a and 1b standardizes and facilitates EHR AKI detection, while identifying additional clinically relevant cases of in-hospital AKI.

Application of the REVEAL risk score calculator 2.0 in the PATENT study

BACKGROUND

Regular risk assessment is recommended in pulmonary arterial hypertension (PAH) management to improve patient outcomes. The REVEAL risk score (RRS) predicts survival in patients with PAH, including those from the PATENT study, which assessed riociguat, a soluble guanylate cyclase stimulator approved for PAH treatment. An updated version, RRS 2.0, has been developed to further refine risk prediction.

METHODS

This post hoc analysis of PATENT-1 and its open-label extension PATENT-2 (n = 396) assessed RRS 2.0 score and risk stratum and their association with survival and clinical worsening-free survival (CWFS).

RESULTS

At PATENT-1 Week 12, riociguat improved RRS 2.0 versus placebo (least-squares mean difference versus placebo: -1.0 [95% confidence interval - 1.4 to -0.6; p < 0.0001]) and more patients improved risk stratum with riociguat (57%) versus placebo (42%). These improvements were maintained at PATENT-2 Week 12. RRS 2.0 score and risk strata at PATENT-1 baseline and Week 12 were significantly associated with survival and CWFS in PATENT-2 (p < 0.0001); change in RRS 2.0 score from PATENT-1 baseline to Week 12 was also significantly associated with outcomes.

CONCLUSIONS

These data suggest that RRS 2.0 has clinical utility in predicting long-term outcomes and monitoring treatment response in patients with PAH.

United States Pulmonary Hypertension Scientific Registry: Baseline Characteristics

BACKGROUND

The treatment, genotyping, and phenotyping of patients with World Health Organization Group 1 pulmonary arterial hypertension (PAH) have evolved dramatically in the last decade.

RESEARCH QUESTION

The United States Pulmonary Hypertension Scientific Registry was established as the first US PAH patient registry to investigate genetic information, reproductive histories, and environmental exposure data in a contemporary patient population.

STUDY DESIGN AND METHODS

Investigators at 15 US centers enrolled consecutively screened adults diagnosed with Group 1 PAH who had enrolled in the National Biological Sample and Data Repository for PAH (PAH Biobank) within 5 years of a cardiac catheterization demonstrating qualifying hemodynamic criteria. Exposure and reproductive histories were collected by using a structured interview and questionnaire. The biobank provided genetic data.

RESULTS

Between 2015 and 2018, a total of 499 of 979 eligible patients with clinical diagnoses of idiopathic PAH (IPAH) or familial PAH (n = 240 [48%]), associated PAH (APAH; n = 256 [51%]), or pulmonary venoocclusive disease/pulmonary capillary hemangiomatosis (n = 3 [1%]) enrolled. The mean age was 55.8 years, average BMI was 29.2 kg/m², and 79% were women. Mean duration between symptom onset and diagnostic catheterization was 1.9 years. Sixty-six percent of patients were treated with more than one PAH medication at enrollment. Past use of prescription weight loss drugs (16%), recreational drugs (27%), and oral contraceptive pills (77%) was common. Women often reported miscarriage (37%), although PAH was rarely diagnosed within 6 months of pregnancy (1.9%). Results of genetic testing identified pathogenic or suspected pathogenic variants in 13% of patients, reclassifying 18% of IPAH patients and 5% of APAH patients to heritable PAH.

INTERPRETATION

Patients with Group 1 PAH remain predominately middle-aged women diagnosed with IPAH or APAH. Delays in diagnosis of PAH persist. Treatment with combinations of PAH-targeted medications is more common than in the past. Women often report pregnancy complications, as well as exposure to anorexigens, oral contraceptives, and/or recreational drugs. Results of genetic tests frequently identify unsuspected heritable PAH.

Outcomes of kidney transplantation using deceased donors with history of diabetes

Deceased diabetic kidneys are increasingly utilized in transplantation. The relationship of donor's history of diabetes to clinical and histological outcomes was examined. Forty-nine diabetic deceased donor kidneys (D-DM) were transplanted into 26 normal (R-N/D-DM) and 23 diabetic recipients (R-DM/D-DM) and compared to 211 diabetic recipients of normal kidneys(R-DM/D-N) and 466 normal recipients of normal kidneys (R-N/D-N). Patient survival at 5 years was 89.7% in R-N/D-N, 96.2% in R-N/D-DM, 80.1% in R-DM/D-N, and a 71.6% in R-DM/D-DM (P = .008). Death-censored graft survival at 5 years was 86.3% in R-N/D-N, 87.4% in R-N/D-DM, 93.5% in R-DM/D-N, and 87.5% in R-DM/D-DM (P = .24). Multivariable regression analysis showed that compared to non-diabetic recipients, diabetic recipients had a 2- to 3-fold increased risk of mortality. In this cohort, there was no impact on death-censored graft survival of diabetic donor status. Only 6 of 26 post-perfusion biopsies showed evidence of diabetic nephropathy (<IIa), and on repeat biopsies 70% showed no evidence of progression. Survival of recipients of diabetic donor kidneys appears dependent on the diabetic status of the recipient with the worst survival being in diabetic recipients of a diabetic donor kidney. In this cohort, donor kidneys had paucity of structural diabetic lesions and most did not show progression.

Clinical outcomes stratified by baseline functional class after initial combination therapy for pulmonary arterial hypertension

Background

Initial combination therapy with ambrisentan and tadalafil reduced the risk of clinical failure events for treatment-naïve participants with pulmonary arterial hypertension (PAH) as compared to monotherapy. Previous studies in PAH have demonstrated greater treatment benefits in more symptomatic participants.

Methods

AMBITION was an event-driven, double-blind study in which participants were randomized 2:1:1 to once-daily initial combination therapy with ambrisentan 10 mg plus tadalafil 40 mg, ambrisentan 10 mg plus placebo, or tadalafil 40 mg plus placebo. In this pre-specified subgroup analysis, we compared the efficacy data between those with functional class (FC) II vs. FC III symptoms at baseline.

Results

This analysis included 500 participants in the previously defined primary analysis set (n = 155 FC II, n = 345 FC III). Comparing combination therapy to pooled monotherapy, the risk of clinical failure events was reduced by 79% (hazard ratio, 0.21 [95% confidence interval: 0.071, 0.63]) for FC II patients and 42% (hazard ratio, 0.58 [95% confidence interval: 0.39, 0.86]) for FC III patients. In a post-hoc analysis, the risk of first hospitalization for worsening PAH was also reduced by combination therapy, particularly for FC II patients (0 combination vs. 11 [14%] pooled monotherapy). Adverse events were frequent but comparable between the subgroups.

Conclusions

Treatment benefit from initial combination therapy appeared at least as great for FC II as for FC III participants. Hospitalizations for worsening PAH were not observed in FC II participants assigned to combination. The present data support an initial combination strategy for newly diagnosed patients even when symptoms are less severe.

Funded by Gilead Sciences, Inc. and GlaxoSmithKline; AMBITION ClinicalTrials.gov number, NCT01178073.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12931-019-1180-1.

Predicting Survival in Patients With Pulmonary Arterial Hypertension: The REVEAL Risk Score Calculator 2.0 and Comparison With ESC/ERS-Based Risk Assessment Strategies

BACKGROUND

Pulmonary arterial hypertension is a progressive, fatal disease. Published treatment guidelines recommend treatment escalation on the basis of regular patient assessment with the goal of achieving or maintaining low-risk status. Various strategies are available to determine risk status. This analysis describes an update of the Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) risk calculator (REVEAL 2.0) and compares it with recently published European Society of Cardiology/Respiratory Society guideline-derived risk assessment strategies.

METHODS

A subpopulation from the US-based registry REVEAL that survived ≥ 1 year postenrollment (baseline for this cohort) was analyzed. For REVEAL 2.0, point values and cutpoints were reassessed, and new variables were evaluated. The Kaplan-Meier method was used to estimate survival at 12 months postbaseline; discrimination was quantified using the c-statistic. Mortality estimates and discrimination were compared between REVEAL 2.0 and Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (COMPERA) and French Pulmonary Hypertension Registry (FPHR) risk assessment strategies. For this comparison, a three-category REVEAL 2.0 score was computed in which patients were classified as low-, intermediate-, or high-risk.

RESULTS

REVEAL 2.0 demonstrated similar discrimination as the original calculator in this subpopulation (c-statistic = 0.76 vs 0.74), provided excellent separation of risk among the risk categories, and predicted clinical worsening as well as mortality in patients who were followed ≥ 1 year. The REVEAL 2.0 three-category score had greater discrimination (c-statistic = 0.73) than COMPERA (c-statistic = 0.62) or FPHR (c-statistic = 0.64). Compared with REVEAL 2.0, COMPERA and FPHR both underestimated and overestimated risk.

CONCLUSIONS

REVEAL 2.0 demonstrates greater risk discrimination than the COMPERA and FPHR risk assessment strategies in patients enrolled in REVEAL. After external validation, the REVEAL 2.0 calculator can assist clinicians and patients in making informed treatment decisions on the basis of individual risk profiles.

TRIAL REGISTRY

ClinicalTrials.gov; No. NCT00370214; URL: www.clinicaltrials.gov.

United States Pulmonary Hypertension Scientific Registry (USPHSR): rationale, design, and clinical implications

Diagnostic World Health Organization (WHO) Group 1 pulmonary arterial hypertension (PAH) and Diagnostic Group 1' pulmonary veno-occlusive disease (PVOD) and/or pulmonary capillary hemangiomatosis (PCH) are progressive and fatal disorders. Past registries provided important insights into these disorders, but did not include hormonal exposures or genomic data. The United States Pulmonary Hypertension Scientific Registry (USPHSR) will provide demographic, physiologic, anorexigen and hormone exposure, genomic, and survival data in the current therapeutic era for 499 patients diagnosed with PAH, PVOD, or PCH. The USPHSR also will explore the relationship between pharmacologic, non-pharmacologic, and dietary hormonal exposures and the increased risk for women to develop idiopathic or heritable PAH.

Early clearance vs persistence of de novo donor-specific antibodies following lung transplantation

BACKGROUND

The natural history of de novo donor-specific antibodies (dnDSA) after lung transplantation is not well-described. We sought to determine the incidence and risk factors associated with dnDSA and compare outcomes between recipients with transient (or isolated) vs persistent dnDSA after transplantation.

METHODS

A single-center review of all lung transplants from 1/2009-7/2013. DSAs were tested eight times in the first year and every 4 months thereafter. Outcomes examined included acute rejection and graft failure.

RESULTS

Median follow-up was 18 months (range: 1-61 months), and 24.6% of 333 first-time lung-only transplant recipients developed a dnDSA. Ethnicity, HLA-DQ mismatches, post-transplantation platelet transfusion and Lung Allocation Score >60 were associated with dnDSA (P<.05). Overall graft survival was worse for dnDSA-positive vs negative recipients (P=.025). Of 323 recipients with 1-year follow-up, 72 (22.2%) developed dnDSA, and in 25 (34.7%), the dnDSA was transient and cleared. Recipients with transient dnDSA were less likely to develop acute rejection than those with persistent dnDSA (P=.007).

CONCLUSIONS

Early post-lung transplantation, dnDSA occurred in 1/4 of recipients, was associated with peri-transplant risk factors and resulted in decreased survival. Spontaneous clearance of dnDSA, seen in one-third of recipients, was associated with a lower risk of acute rejection.

The Intersection of Pulmonary Hypertension and Solid Organ Transplantation

Pulmonary hypertension (PH) is a complication and marker of disease severity in many parenchymal lung diseases. It also is a frequent complication of portal hypertension and negatively impacts survival with liver transplant. Pulmonary hypertension is frequently diagnosed in patients with end-stage renal disease who are undergoing dialysis, and it has recently been demonstrated to adversely affect posttransplant outcome in this patient population even though the mechanism of PH is substantially different from that associated with liver disease. The presence of PH in patients with heart failure is frequent, and the necessity for PH therapy prior to heart transplant has evolved in the last decade. We review the frequency of and risk factors for PH in recipients of and candidates for lung, liver, heart, and renal transplants as well as the impact of this diagnosis on posttransplant outcomes.

Longitudinal change in pulmonary arterial capacitance as an indicator of prognosis and response to therapy and in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a chronic progressive disease that leads to right heart failure and death. Pulmonary arterial capacitance (PAC), defined as stroke volume divided by the pulmonary pulse pressure, has been identified as a prognostic factor in PAH. The impact of changes in PAC over time, however, is unclear. We evaluated changes in PAC over time to determine if such changes predicted transplant-free survival. A single-center retrospective study of consecutive group 1 PAH patients who had two or more right heart catheterizations (RHC) between January 2007 and June 2016 was undertaken. Hemodynamic data, clinical data, and outcomes were collected. Univariate and multivariate Cox proportional-hazards modelling to identify the contribution of risk factors for a composite outcome of death or lung transplantation was done. Mixed-effects logistic regression was performed to investigate the association between the change in PAC value over time and the composite outcome. A P value < 0.05 was considered significant. In total, 109 consecutive patients with a total of 300 RHC data were identified. PAC correlated inversely with functional status ( P < 0.001) and inversely with pulmonary vascular resistance ( P < 0.001). PAC values increased with the addition of new PAH-specific medications. Mixed effects logistic regression modeling using longitudinal data showed that a decrease in PAC over the study period was associated with increased mortality and transplantation (adjusted P = 0.039) over the study period. Change in PAC was a better predictor of outcome over the study period than baseline PAC or changes in other hemodynamic or clinical parameters. Decreases in PAC were predictive of increased mortality or transplantation in patients with group 1 PAH. There was a trend towards increased PAC in response to the addition of a PAH-specific medication. Our data support the use of PAC as a therapeutic target in PAH.

Initial combination therapy with ambrisentan and tadalafil in connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH): subgroup analysis from the AMBITION trial

Background

Patients with connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH), in particular systemic sclerosis (SSc), had an attenuated response compared with idiopathic PAH in most trials. Thus, there is uncertainty regarding the benefit of PAH-targeted therapy in some forms of CTD-PAH.

Objective

To explore the safety and efficacy of initial combination therapy with ambrisentan and tadalafil versus ambrisentan or tadalafil monotherapy in patients with CTD-PAH and SSc-PAH enrolled in the AMBITION trial.

Methods

This was a post hoc analysis of patients with CTD-PAH and SSc-PAH from AMBITION, an event-driven, double-blind trial in patients with WHO functional class II/III PAH. Treatment-naive patients were randomised 2:1:1 to once-daily initial combination therapy with ambrisentan plus tadalafil or monotherapy with ambrisentan or tadalafil, respectively. The primary endpoint was time to the first clinical failure event (first occurrence of death, hospitalisation for worsening PAH, disease progression or unsatisfactory long-term clinical response).

Results

In the primary analysis set (N=500), 187 patients had CTD-PAH, of whom 118 had SSc-PAH. Initial combination therapy reduced the risk of clinical failure versus pooled monotherapy in each subgroup: CTD-PAH (HR 0.43 (95% CI 0.24 to 0.77)) and SSc-PAH (0.44 (0.22 to 0.89)). The most common AE was peripheral oedema, which was reported more frequently with initial combination therapy than monotherapy in the two PAH subgroups. The relative frequency of adverse events between those on combination therapy versus monotherapy was similar across subgroups.

Conclusions

This post hoc subgroup analysis provides evidence that CTD-PAH and SSc-PAH patients benefit from initial ambrisentan and tadalafil combination therapy.

Trial registration number

NCT01178073, post results.

Endothelin-1 Pathway Polymorphisms and Outcomes in Pulmonary Arterial Hypertension

RATIONALE

Pulmonary arterial hypertension (PAH) is a progressive fatal disease. Variable response and tolerability to PAH therapeutics suggests that genetic differences may influence outcomes. The endothelin pathway is central to pulmonary vascular function, and several polymorphisms and/or mutations in the genes coding for endothelin (ET)-1 and its receptors correlate with the clinical manifestations of other diseases.

OBJECTIVES

To examine the interaction of ET-1 pathway polymorphisms and treatment responses of patients with PAH treated with ET receptor antagonists (ERAs).

METHODS

A total of 1,198 patients with PAH were prospectively enrolled from 45 U.S. and Canadian pulmonary hypertension centers or retrospectively from global sites participating in the STRIDE (Sitaxsentan To Relieve Impaired Exercise) trials. Comprehensive objective measures including a 6-minute-walk test, Borg dyspnea score, functional class, and laboratory studies were completed at baseline, before the initiation of ERAs, and repeated serially. Single-nucleotide polymorphisms from ET-1 pathway candidate genes were selected from a completed genome-wide association study performed on the study cohort.

MEASUREMENTS AND MAIN RESULTS

Patient efficacy outcomes were analyzed for a relationship between ET-1 pathway polymorphisms and clinical efficacy using predefined, composite positive and negative outcome measures in 715 European descent samples. A single-nucleotide polymorphism (rs11157866) in the G-protein alpha and gamma subunits gene was significantly associated, accounting for multiple testing, with a combined improvement in functional class and 6-minute-walk distance at 12 and 18 months and marginally significant at 24 months.

CONCLUSIONS

ET-1 pathway associated polymorphisms may influence the clinical efficacy of ERA therapy for PAH. Further prospective studies are needed.

Five-Year outcomes of patients enrolled in the REVEAL Registry

BACKGROUND

Pulmonary arterial hypertension (PAH) is a rare, severe disease characterized by worsening right-sided heart failure, decreasing functional status, and poor survival. The present study characterizes the 5-year survival in the United States of a new and previous diagnosis of PAH in patients stratified by baseline functional class (FC). The Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry) is a 55-center observational US registry of the demographics, disease course, and management of patients with World Health Organization (WHO) group 1 PAH.

METHODS

The REVEAL Registry enrolled newly and previously diagnosed patients aged ≥ 3 months with WHO group 1 PAH consecutively from March 2006 to December 2009. Demographics, disease characteristics, and hemodynamic data were collected at enrollment. Survival analysis was conducted by FC and other subgroups in patients aged ≥ 18 years.

RESULTS

Survival differences between previously diagnosed and newly diagnosed patients at 1 year (90.4% vs 86.3%) were maintained to 5 years; 5-year survival for previously diagnosed patients was 65.4% compared with 61.2% for newly diagnosed patients. Previously diagnosed patients in FC I, II, III, and IV had an estimated 5-year survival rate of 88.0%, 75.6%, 57.0%, and 27.2%, respectively, compared with 72.2%, 71.7%, 60.0%, and 43.8% for newly diagnosed patients in FC I, II, III, and IV, respectively.

CONCLUSIONS

Patient survival of advanced PAH remains poor at 5 years despite treatment advances. New York Heart Association FC remains one of the most important predictors of future survival. These observations reinforce the importance of continuous monitoring of FC in patients with PAH.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov.

Initial Use of Ambrisentan plus Tadalafil in Pulmonary Arterial Hypertension

BACKGROUND

Data on the effect of initial combination therapy with ambrisentan and tadalafil on long-term outcomes in patients with pulmonary arterial hypertension are scarce.

METHODS

In this event-driven, double-blind study, we randomly assigned, in a 2:1:1 ratio, participants with World Health Organization functional class II or III symptoms of pulmonary arterial hypertension who had not previously received treatment to receive initial combination therapy with 10 mg of ambrisentan plus 40 mg of tadalafil (combination-therapy group), 10 mg of ambrisentan plus placebo (ambrisentan-monotherapy group), or 40 mg of tadalafil plus placebo (tadalafil-monotherapy group), all administered once daily. The primary end point in a time-to-event analysis was the first event of clinical failure, which was defined as the first occurrence of a composite of death, hospitalization for worsening pulmonary arterial hypertension, disease progression, or unsatisfactory long-term clinical response.

RESULTS

The primary analysis included 500 participants; 253 were assigned to the combination-therapy group, 126 to the ambrisentan-monotherapy group, and 121 to the tadalafil-monotherapy group. A primary end-point event occurred in 18%, 34%, and 28% of the participants in these groups, respectively, and in 31% of the pooled-monotherapy group (the two monotherapy groups combined). The hazard ratio for the primary end point in the combination-therapy group versus the pooled-monotherapy group was 0.50 (95% confidence interval [CI], 0.35 to 0.72; P<0.001). At week 24, the combination-therapy group had greater reductions from baseline in N-terminal pro-brain natriuretic peptide levels than did the pooled-monotherapy group (mean change, -67.2% vs. -50.4%; P<0.001), as well as a higher percentage of patients with a satisfactory clinical response (39% vs. 29%; odds ratio, 1.56 [95% CI, 1.05 to 2.32]; P=0.03) and a greater improvement in the 6-minute walk distance (median change from baseline, 48.98 m vs. 23.80 m; P<0.001). The adverse events that occurred more frequently in the combination-therapy group than in either monotherapy group included peripheral edema, headache, nasal congestion, and anemia.

CONCLUSIONS

Among participants with pulmonary arterial hypertension who had not received previous treatment, initial combination therapy with ambrisentan and tadalafil resulted in a significantly lower risk of clinical-failure events than the risk with ambrisentan or tadalafil monotherapy. (Funded by Gilead Sciences and GlaxoSmithKline; AMBITION ClinicalTrials.gov number, NCT01178073.).

Hospitalization and survival in patients using epoprostenol for injection in the PROSPECT observational study

BACKGROUND:

Few studies have prospectively reported outcomes in patients with pulmonary arterial hypertension (PAH) treated with epoprostenol in the modern-day era of oral therapy and combination treatments. The Registry to Prospectively Describe Use of Epoprostenol for Injection (Veletri, prolonged room temperature stable-epoprostenol [RTS-Epo]) in Patients with Pulmonary Arterial Hypertension (PROSPECT) was established to prospectively describe the course of PAH in patients prescribed RTS-Epo.

METHODS:

PROSPECT is a multicenter, US-based drug registry of primarily group 1 patients with PAH treated with RTS-Epo who were parenteral-naive or parenteral-transitioned at enrollment. Patients were followed until discontinuation of RTS-Epo, withdrawal, loss to follow-up, death, or end of study (maximum 1 year). One-year freedom from hospitalization (FH) and survival estimates were summarized by prostacyclin history (parenteral-naive or parenteral-transitioned), sex, and chronic renal insufficiency (CRI).

RESULTS:

A total of 336 patients were included. The overall 1-year FH estimate was 51.0% ± 2.8% and was lower in parenteral-naive patients than parenteral-transitioned patients (42.8% ± 4.3% vs 57.1% ± 3.7%, respectively; P = .002). FH estimates were lower in male patients than female patients (38.3% ± 5.9% vs 54.6% ± 3.2%, respectively; P < .015) and in patients with CRI than patients without CRI (17.0% ± 8.4% vs 53.7% ± 2.9%, respectively; P < .001). The overall 1-year survival estimate was 84.0% ± 2.1%. Survival was poorer in parenteral-naive patients, male patients, and patients with CRI.

CONCLUSIONS:

Risk of hospitalization and mortality remain high in patients with PAH. In particular, patients who are parenteral-naive at initiation of RTS-Epo therapy, male patients, and patients with CRI require close monitoring and aggressive clinical management.

Validation of two predictive models for survival in pulmonary arterial hypertension

The French Pulmonary Hypertension Network (FPHN) registry and the Registry to Evaluate Early And Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL) have developed predictive models for survival in pulmonary arterial hypertension (PAH). In this collaboration, we assess the external validity (or generalisability) of the FPHN ItinérAIR-HTAP predictive equation and the REVEAL risk score calculator.

Validation cohorts approximated the eligibility criteria defined for each model. The REVEAL cohort comprised 292 treatment-naïve, adult patients diagnosed <1 year prior to enrolment with idiopathic, familial or anorexigen-induced PAH. The FPHN cohort comprised 1737 patients with group 1 PAH.

Application of FPHN parameters to REVEAL and REVEAL risk scores to FPHN demonstrated estimated hazard ratios that were consistent between studies and had high probabilities of concordance (hazard ratios of 0.72, 95% CI 0.64–0.80, and 0.73, 95% CI 0.70–0.77, respectively).

The REVEAL risk score calculator and FPHN ItinérAIR-HTAP predictive equation showed good discrimination and calibration for prediction of survival in the FPHN and REVEAL cohorts, respectively, suggesting prognostic generalisability in geographically different PAH populations. Once prospectively validated, these may become valuable tools in clinical practice.

Predicting outcomes in pulmonary arterial hypertension based on the 6-minute walk distance

BACKGROUND

Clinical studies of pulmonary arterial hypertension have used the change in the 6-minute walk distance (6MWD) as a clinical end point; however, its association with survival outcomes has not been well established. In this analysis, we examined the prognostic value of the baseline 6MWD, absolute thresholds of the 6MWD, and change in the 6MWD.

METHODS

Patients in the Registry to Evaluate Early and Long-Term Pulmonary Arterial Hypertension Disease Management (REVEAL) with 6MWD at enrollment, with or without a follow-up assessment within the first year of observation, were included. Kaplan-Meier survival estimates were computed for sub-sets with baseline 6MWD results that were above or below all possible thresholds and for sub-sets with a change in the 6MWD that was 10 percentage points above or below all possible thresholds, including improvement thresholds and worsening thresholds. Multivariable Cox regression models assessed the effect of improvement and worsening in the 6MWD on 1-year survival, adjusted for baseline factors.

RESULTS

One-year survival estimates were higher for patients with a baseline 6MWD above vs below a threshold, although no specific threshold was more prognostic than another. In a model adjusted for the baseline 6MWD and risk score, worsening of the 6MWD over time significantly predicted decreased survival, but improvement in the 6MWD did not affect survival.

CONCLUSIONS

No 6MWD improvement threshold carries particular prognostic value. Improvement in the 6MWD was not associated with survival, but worsening of the 6MWD was strongly and significantly associated with poor prognosis.

Imatinib mesylate as add-on therapy for pulmonary arterial hypertension: results of the randomized IMPRES study

BACKGROUND

By its inhibitory effect on platelet-derived growth factor signaling, imatinib could be efficacious in treating patients with pulmonary arterial hypertension (PAH).

METHODS AND RESULTS

Imatinib in Pulmonary Arterial Hypertension, a Randomized, Efficacy Study (IMPRES), a randomized, double-blind, placebo-controlled 24-week trial, evaluated imatinib in patients with pulmonary vascular resistance ≥ 800 dyne·s·cm(-5) symptomatic on ≥ 2 PAH therapies. The primary outcome was change in 6-minute walk distance. Secondary outcomes included changes in hemodynamics, functional class, serum levels of N-terminal brain natriuretic peptide, and time to clinical worsening. After completion of the core study, patients could enter an open-label long-term extension study. Of 202 patients enrolled, 41% patients received 3 PAH therapies, with the remainder on 2 therapies. After 24 weeks, the mean placebo-corrected treatment effect on 6-minute walk distance was 32 m (95% confidence interval, 12-52; P=0.002), an effect maintained in the extension study in patients remaining on imatinib. Pulmonary vascular resistance decreased by 379 dyne·s·cm(-5) (95% confidence interval, -502 to - 255; P<0.001, between-group difference). Functional class, time to clinical worsening, and mortality did not differ between treatments. Serious adverse events and discontinuations were more frequent with imatinib than placebo (44% versus 30% and 33% versus 18%, respectively). Subdural hematoma occurred in 8 patients (2 in the core study, 6 in the extension) receiving imatinib and anticoagulation.

CONCLUSIONS

Imatinib improved exercise capacity and hemodynamics in patients with advanced PAH, but serious adverse events and study drug discontinuations were common. Further studies are needed to investigate the long-term safety and efficacy of imatinib in patients with PAH.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00902174 (core study); NCT01392495 (extension).

Delay in recognition of pulmonary arterial hypertension: factors identified from the REVEAL Registry

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive and fatal disorder. Despite the emergence of effective therapy, PAH is commonly at an advanced stage when recognized. Factors associated with a prolonged symptomatic period before the recognition of PAH have not been fully evaluated.

METHODS

The Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry) enrolled 2,967 US adult patients with PAH from March 2006 to September 2007. Patients were considered to have delayed disease recognition if > 2 years elapsed between symptom onset and the patient receiving a PAH diagnosis, starting on PAH-specific therapy, or receiving a diagnosis by right-sided heart catheterization.

RESULTS

In 21.1% of patients, symptoms were experienced for > 2 years before PAH was recognized. Patients with onset of PAH symptoms before age 36 years showed the highest likelihood of delayed disease recognition (OR, 3.07; 95% CI, 2.03-4.66). History of obstructive airways disease (OR, 1.93; 95% CI, 1.5-2.47) and sleep apnea (OR, 1.72; 95% CI, 1.33-2.22) were independently associated with delayed PAH recognition. Six-minute walk distance < 250 m (OR, 1.91; 95% CI, 1.16-3.13), right atrial pressure < 10 mm Hg (OR, 1.77; 95% CI, 1.26-2.48), and pulmonary vascular resistance < 10 Wood units (OR, 1.28; 95% CI, 1.02-1.60) were also associated with delayed disease recognition, but sex, race/ethnicity, and geographic region showed no association.

CONCLUSIONS

One in five patients in the REVEAL Registry who were diagnosed with PAH reported symptoms for > 2 years before their disease was recognized. Younger individuals and patients with histories of common respiratory disorders were most likely to experience delayed PAH recognition.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov.

A prospective echocardiographic evaluation of pulmonary hypertension in chronic hemodialysis patients in the United States: prevalence and clinical significance

BACKGROUND

Pulmonary hypertension (PH), a disease which carries substantial morbidity and mortality, has been reported to occur in 25%-45% of dialysis patients. No prospective evaluation of the prevalence or clinical significance of PH in chronic dialysis patients in the United States (US) has been undertaken.

METHODS

Echocardiograms were performed prospectively in chronic hemodialysis patients prior to dialysis at a single dialysis center. PH was defined as a tricuspid regurgitant jet ≥2.5 m/s and "more severe PH" as ≥3.0 m/s. Clinical outcomes recovered were all-cause hospitalizations and death at 12 months.

RESULTS

In a cohort of 90 patients, 42 patients (47%) met the definition of PH. Of those, 18 patients (20%) met the definition of more severe PH. At 12 months, mortality was significantly higher in patients with PH (26%) compared with patients without PH (6%). All-cause hospitalizations were similar in patients with PH and without PH. Echocardiographic findings suggesting impaired left ventricular function and elevated pulmonary capillary wedge pressure were significantly associated with PH.

CONCLUSION

This prospective cross-sectional study of a single dialysis unit suggests that PH may be present in nearly half of US dialysis patients and when present is associated with increased mortality. Echocardiographic findings demonstrate an association between elevated filling pressures, elevated pulmonary artery pressures, and higher mortality, suggesting that the PH may be secondary to diastolic dysfunction and compounded by volume overload.

Computed axial tomography evidence of left atrial enlargement: a predictor of elevated pulmonary capillary wedge pressure in pulmonary hypertension

BACKGROUND

One of the commonest causes of pulmonary hypertension (PH) is left heart dysfunction associated with elevated pulmonary capillary wedge pressure (PCWP). In contrast, the pathology of pulmonary arterial hypertension (PAH) originates in the pulmonary vascular bed. Accurate diagnosis of PAH requires right heart catheterization (RHC) with normal PCWP. This study examines the role of computed tomography of the chest (CT chest) in evaluating left atrial (LA) size as an indicator of elevated PCWP in patients undergoing PH evaluation.

METHODS

CT chest and RHC data were reviewed in 37 subjects at the Baylor PH Center. Both subjective estimates and objective measurements of left atrial size from the CT chest were recorded separately by 3 investigators. Patients were categorized as Group I (small-normal LA) and Group II (large LA) and RHC results compared.The objective and subjective measurements were compared by receiver operator characteristic (ROC).

RESULTS

The mean PCWP was 12 +/- 6 mmHg in Group I and 21 +/- 7 mmHg in Group II (P = 0.001). The estimated LA area was 19.4 +/- 4.9 cm(2) in Group I and 39.9 +/- 7.6 cm(2) in Group II (mean +/- SD; P < 0.001). The estimated LA area, corrected for the chest wall length, was 0.78 +/- 0.19 cm(2) and 1.65 +/- 0.26 cm(2) in Groups I and II, respectively (P < 0.001). Significant correlations were found between uncorrected PCWP and LA area (R = 0.45, P = 0.005), corrected PCWP and LA area (R = 0.47, P = 0.003), and the subjective observer impression of LA enlargement and measured PCWP (R = 0.51, P = 0.001).

CONCLUSION

In this pilot study, enlarged LA area on the CT chest was associated with an elevated PCWP on RHC. For patients undergoing PH evaluation, increased LA area on CT chest could suggest left heart dysfunction in patients as a possible cause of PH.

Addition of sildenafil to long-term intravenous epoprostenol therapy in patients with pulmonary arterial hypertension: a randomized trial

BACKGROUND

Oral sildenafil and intravenous epoprostenol have independently been shown to be effective in patients with pulmonary arterial hypertension.

OBJECTIVE

To investigate the effect of adding oral sildenafil to long-term intravenous epoprostenol in patients with pulmonary arterial hypertension.

DESIGN

A 16-week, double-blind, placebo-controlled, parallel-group study.

SETTING

Multinational study at 41 centers in 11 countries from 3 July 2003 to 27 January 2006.

PATIENTS

267 patients with pulmonary arterial hypertension (idiopathic, associated anorexigen use or connective tissue disease, or corrected congenital heart disease) who were receiving long-term intravenous epoprostenol therapy.

INTERVENTION

Patients were randomly assigned to receive placebo or sildenafil, 20 mg three times daily, titrated to 40 mg and 80 mg three times daily, as tolerated, at 4-week intervals. Of 265 patients who received treatment, 256 (97%) patients (123 in the placebo group and 133 in the sildenafil group) completed the study.

MEASUREMENTS

Change from baseline in exercise capacity measured by 6-minute walk distance (primary end point) and hemodynamic measurements, time to clinical worsening, and Borg dyspnea score (secondary end points).

RESULTS

A placebo-adjusted increase of 28.8 meters (95% CI, 13.9 to 43.8 meters) in the 6-minute walk distance occurred in patients in the sildenafil group; these improvements were most prominent among patients with baseline distances of 325 meters or more. Relative to epoprostenol monotherapy, addition of sildenafil resulted in a greater change in mean pulmonary arterial pressure by -3.8 mm Hg (CI, -5.6 to -2.1 mm Hg); cardiac output by 0.9 L/min (CI, 0.5 to 1.2 L/min); and longer time to clinical worsening, with a smaller proportion of patients experiencing a worsening event in the sildenafil group (0.062) than in the placebo group (0.195) by week 16 (P = 0.002). Health-related quality of life also improved in patients who received combined therapy compared with those who received epoprostenol monotherapy. There was no effect on the Borg dyspnea score. Of the side effects generally associated with sildenafil treatment, the most commonly reported in the placebo and sildenafil groups, respectively, were headache (34% and 57%; difference, 23 percentage points [CI, 12 to 35 percentage points]), dyspepsia (2% and 16%; difference, 13 percentage points [CI, 7 to 20 percentage points]), pain in extremity (18% and 25%; difference, 8 percentage points [CI, -2 to 18 percentage points]), and nausea (18% and 25%; difference, 8 percentage points [CI, -2 to 18 percentage points]).

LIMITATIONS

The study excluded patients with pulmonary arterial hypertension associated with other causes. There was an imbalance in missing data between groups, with 8 placebo recipients having no postbaseline walk assessment compared with 1 sildenafil recipient. These patients were excluded from the analysis.

CONCLUSION

In some patients with pulmonary arterial hypertension, the addition of sildenafil to long-term intravenous epoprostenol therapy improves exercise capacity, hemodynamic measurements, time to clinical worsening, and quality of life, but not Borg dyspnea score. Increased rates of headache and dyspepsia occurred with the addition of sildenafil.

Correlation of chest radiograph pattern with genotype, age, and gender in adult cystic fibrosis: a single-center study

INTRODUCTION

Cystic fibrosis (CF) is a common lethal genetic disorder. The aim of this study was to determine the common chest radiograph (CXR) patterns in adult CF, and correlate disease distribution on CXRs with genotype, age, and gender.

METHODS

One hundred nine CF patients treated at Baylor Adult Cystic Fibrosis Center were identified. The intake CXR was reviewed and characterized as diffuse bilateral (DB), unilateral, upper lobe (UL), and lower lobe (LL) disease, or relatively normal. Lack of intake CXR, and/or genotype excluded 41 patients from analysis.

RESULTS

Of 68 patients, 38 were homozygous for DeltaF508 and 30 were heterozygous. Mean age of the population was 30 +/- 8 years (+/- SD) [range, 18 to 48 years]. The most common CXR pattern was DB; 62% had DB, 28% had UL, and 7% had LL predominance. This is in contrast to the UL-predominant CXR pattern commonly described in the pediatric population. In 18 DB patients, archived pediatric films were available, and the average patient age was 15.7 years. DB pattern was present in 16 of 18 CXRs that antedated adult intake CXRs by an average of 12.7 years. Homozygous DeltaF508 genotype was identified in 56% of patients and did not distinguish radiologic phenotypes. There was no association between radiograph pattern and identified infecting/colonizing organisms and percentage of predicted FEV(1).

CONCLUSIONS

CF has commonly been reported as an UL disease. However, in this study of adult patients, the common pattern observed was DB. A small subgroup analysis suggests that DB disease was not a pattern of disease evolution but may be present from disease onset.

Selective endothelin A receptor antagonism with sitaxsentan for pulmonary arterial hypertension associated with connective tissue disease

INTRODUCTION

Endothelin receptor antagonism has become an important component in the treatment of pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD). The purpose of this study was to analyse the safety and effectiveness of sitaxsentan, a selective antagonist of the ET(A) receptor, in a cohort of patients with PAH and CTD. Short-term clinical and haemodynamic effects and longer-term follow-up data are presented.

METHODS

A post hoc subgroup analysis was performed on 42 patients who had PAH associated with CTD, out of a group of 178 patients enrolled in a 12-week, double-blind, randomised clinical trial of sitaxsentan versus placebo. Data from 33 patients assigned to sitaxsentan 100 mg or 300 mg daily were pooled and compared with nine placebo-treated patients. There were 41 patients entered into the blinded extension study, in which all patients received either 100 mg or 300 mg sitaxsentan once daily.

RESULTS

Patients treated with sitaxsentan had a mean (SD) increase in 6 minute walk distance of 20 (5) m from baseline to week 12 (p = 0.037), whereas the placebo group had a decrease of 38 (84) m, resulting in a placebo-subtracted treatment effect of 58 m (p = 0.027). Parallel improvements in quality of life and haemodynamics were also observed. No patient discontinued their drug during the 12-week trial. In the blinded extension study (median treatment duration 26 weeks), more patients were in functional class I-II than in III-IV (p<0.001) at the end of the study compared with the start of active therapy. Elevation of hepatic transaminase levels occurred in two patients.

CONCLUSIONS

Sitaxsentan appears to be efficacious in patients with PAH associated with CTD.