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Find video protocols related to scientific articles indexed in Pubmed.
Outcome of pulmonary endarterectomy in symptomatic chronic thromboembolic disease.
Eur. Respir. J.
PUBLISHED: 09-20-2014
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Chronic thromboembolic disease is characterised by persistent pulmonary thromboembolic occlusions without pulmonary hypertension. Early surgical treatment with pulmonary endarterectomy may improve symptoms and prevent disease progression. We sought to assess the outcome of pulmonary endarterectomy in symptomatic patients with chronic thromboembolic disease. Patients with symptomatic chronic thromboembolic disease and a mean pulmonary artery pressure <25 mmHg at baseline with right heart catheterisation and treated with pulmonary endarterectomy between January 2000 and July 2013 were identified. Patients were reassessed at 6 months and at 1 year following surgery. A total of 42 patients underwent surgery and the median length of stay in hospital was 11 days. There was no in-hospital mortality but complications occurred in 40% of patients. At 1 year, following surgery, 95% of the patients remained alive. There was a significant symptomatic improvement with 95% of patients in the New York Heart Association functional classes I or II at 6 months. There was a significant improvement in quality of life assessed by the Cambridge pulmonary hypertension outcome review questionnaire. In this carefully selected cohort of chronic thromboembolic disease patients, pulmonary endarterectomy resulted in significant improvement in symptoms and quality of life. Appropriate patient selection is paramount given the known surgical morbidity and mortality, and surgery should only be performed in expert centres.
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Cardiopulmonary exercise testing suggests a beneficial response to pulmonary endarterectomy in a patient with chronic thromboembolic obstruction and normal preoperative pulmonary hemodynamics.
Pulm Circ
PUBLISHED: 07-10-2014
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Pulmonary endarterectomy offers a symptomatic and survival benefit in patients with chronic thromboembolic pulmonary hypertension through sustained improvement in right ventricular function. However, its role in patients with symptom limitation, chronic thrombotic obstruction, and a normal pulmonary hemodynamic profile is less clear. Cardiopulmonary exercise testing (CPET) stresses the cardiopulmonary system and has a characteristic response in pulmonary hypertension. CPET may therefore reveal abnormalities in patients with chronic thrombotic obstruction where hemodynamic investigations conducted at rest are reassuring. Using incremental CPET, we demonstrated improvements in right ventricular performance and ventilatory efficiency following pulmonary endarterecomy in a patient with preoperative exercise limitation and normal pulmonary hemodynamics. Careful evaluation of exercise responses may extend the potential benefit offered by pulmonary endarterectomy in patients with chronic thromboembolic obstruction irrespective of their resting hemodynamic profile.
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Right ventricular reverse remodeling after pulmonary endarterectomy: magnetic resonance imaging and clinical and right heart catheterization assessment.
Pulm Circ
PUBLISHED: 07-10-2014
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The objective of this study was to assess the effect of pulmonary endarterectomy (PEA) on right ventricular (RV) reverse remodeling using magnetic resonance imaging (MRI) and to correlate MRI findings with clinical and hemodynamic outcomes postsurgery. We performed a retrospective analysis in 72 patients undergoing PEA surgery in whom MRI and right heart catheterization (RHC) were performed preoperation and 3 months postoperation. RV volumes and mass were assessed by MRI. Continuous variables were expressed as means, changes were compared with a paired t test, and associations between the variables were explored using Pearson correlation coefficients. The mean age was 57 years, and 51% were male. Both RV end-diastolic volume (EDV; 176-117 mL; P < 0.001) and RV end-systolic volume (ESV; 129-64 mL; P < 0.001) reduced significantly following PEA. Preoperative pulmonary artery pressure (PAP) correlated moderately with ESV (r = 0.46, P < 0.001). Postoperatively, PAP correlated with EDV (r = 0.45, P < 0.001) and ESV (r = 0.44, P < 0.001). Moderate correlation was present between hemodynamic parameters: PAP, pulmonary vascular resistance, and right atrial pressure with pre- and postoperation end-systolic and end-diastolic RV mass (P < 0.001). RHC and MRI measurements of cardiac output and RV volumes were significantly different (P < 0.001). In conclusion, RV reverse remodeling, as measured by improvement in RV volumes and mass by MRI, was observed for 3 months in patients who underwent PEA surgery. This is the largest series of patients with pre- and post-PEA MRI assessment so far reported. MRI detects changes in parameters reflecting cardiac remodeling and pulmonary clearance, but measurements are significantly different from those of RHC.
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Demographics, clinical characteristics, health resource utilization and cost of chronic thromboembolic pulmonary hypertension patients: retrospective results from six European countries.
BMC Health Serv Res
PUBLISHED: 05-30-2014
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Chronic Thromboembolic Pulmonary Hypertension (CTEPH) results from incomplete resolution of a pulmonary embolus, leading to pulmonary hypertension and progressive right heart failure and death. We aimed to describe the demographics, treatment patterns, health resource utilization and related costs of patients with CTEPH.
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Right ventricle functional assessment: have new techniques supplanted the old faithful conductance catheter?
Cardiol Rev
PUBLISHED: 03-14-2014
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This review explores the historical development of conductance catheterization of the human right ventricle (RV) and its current diagnostic role in assessing RV function in an era of contemporary noninvasive imaging. Significant advances in echocardiography, cardiothoracic computed tomography, and cardiac magnetic resonance in the last decade have led a paradigm shift away from invasive hemodynamic assessment toward noninvasive measurement of RV function. However, imaging modalities are not without some disadvantages. For example, they do not provide the beat-to-beat pressure-volume assessment that is obtained by conductance catheterization, which is still arguably the gold standard for measuring cardiac performance. Right heart catheterization remains an integral part of the assessment of patients with RV dysfunction, and a burgeoning interest in early RV insufficiency in a range of cardiopulmonary diseases has brought the detailed interrogation of RV function back into focus. Although conductance volume assessment of the RV is more limited than the left ventricle, the scope for improving the understanding of RV adaptation to pulmonary and valvular pathologies and RV myocardial disease by using a conductance catheter still exists. We review the up-to-date functional applications of echocardiography and computed tomography/cardiac magnetic resonance to assess the RV and illustrate the potential of contemporary conductance catheter techniques to complement noninvasive imaging in the assessment of RV function.
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Riociguat for pulmonary hypertension.
Expert Rev Clin Pharmacol
PUBLISHED: 03-03-2014
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Pulmonary hypertension, an elevation of the mean pulmonary artery pressure ?25 mmHg, ultimately leads to premature death due to right ventricular dysfunction. Ten treatments from three classes of drugs are licensed for the management of pulmonary arterial hypertension. These treatments have improved exercise capacity but median survival is still poor. Additionally there are no licensed therapies for the other groups of pulmonary hypertension. Riociguat is a novel drug that stimulates soluble guanylate cyclase independently of nitric oxide and in synergy with nitric oxide. This review summarises the available evidence for riociguat in the treatment across all groups of pulmonary hypertension with a focus on pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.
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Chronic thromboembolic pulmonary hypertension: time for research in pathophysiology to catch up with developments in treatment.
F1000Prime Rep
PUBLISHED: 01-01-2014
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The modern treatment era in chronic thromboembolic disease has seen significant advances in both surgical and medical treatment. One such treatment, the pulmonary endarterectomy (where established chronic organized thrombus is removed), has dramatically affected morbidity and mortality. These advances have outstripped basic research into the causes and pathophysiology of disease, which remain largely poorly understood. In this review, we will set out to explain some of the historical reasons for this, including the difficulties inherent in human studies and the lack of good animal models. We will review some of the recent advances in pathophysiology from registries and translational research, and we will summarize the treatment options, with some discussion of very recently published work, including medical and surgical treatments, both traditional and more experimental work in non-invasive techniques.
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Maximal cardiac output determines 6 minutes walking distance in pulmonary hypertension.
PLoS ONE
PUBLISHED: 01-01-2014
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The 6 minutes walk test (6MWT) is often shown to be the best predictor of mortality in pulmonary hypertension (PH) probably because it challenges the failing heart to deliver adequate cardiac output. We hypothesised that the 6MWT elicits maximal cardiac output as measured during a maximal cardiopulmonary exercise testing (CPET).
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Right Ventricular Dysfunction in Chronic Thromboembolic Obstruction of the Pulmonary Artery.
J. Appl. Physiol.
PUBLISHED: 12-19-2013
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Introduction: Pressure volume loops describe dynamic ventricular performance, relevant to patients with and at risk of pulmonary hypertension. We used conductance catheter-derived pressure volume loops to measure RV mechanics in patients with chronic thromboembolic pulmonary arterial obstruction at different stages of pathological adaptation. Materials and Methods: Resting conductance catheterization was performed in twenty-four patients;10 with chronic thromboembolic pulmonary hypertension(CTEPH), 7 with chronic thromboembolic disease without pulmonary hypertension(CTED) and 7 controls. To assess the validity of conductance measurements, RV volumes were compared in a subset of 8 patients with contemporaneous cardiac magnetic resonance (CMR). Results: Control, CTED and CTEPH groups showed different pressure volume loop morphology, most notable during systolic ejection. Prolonged diastolic relaxation was seen in patients with CTED and CTEPH (Tau=56.2±6.7 (Controls) vs 69.7±10.0 (CTED) vs 67.9±6.2ms (CTEPH), p=0.02). Control and CTED groups had lower afterload (Ea) and contractility (Ees) compared to the CTEPH group (Ea=0.30±0.10 vs 0.52±0.24 vs 1.92±0.70mmHg/ml respectively, p<0.001), (Ees=0.44±0.20 vs 0.59±0.15 vs 1.13±0.43mmHg/ml, p<0.01) with more efficient ventriculo-arterial coupling (Ees/Ea=0.46±0.30 vs 1.27±0.36 vs 0.60±0.18 respectively, p<0.001). Stroke volume assessed by CMR and conductance showed closest agreement (mean bias +9ml, 95%CI -1 to +19ml) compared with end-diastolic volume (+48ml, -16 to 111ml) and end-systolic volume (+37ml,-21 to 94 ml). Conclusions: RV conductance catheterization detects novel alteration in pressure volume loop morphology and delayed RV relaxation in CTED which distinguish this group from controls. The observed agreement in stroke volume assessed by CMR and conductance suggest RV mechanics are usefully measured by conductance catheter in chronic thromboembolic obstruction.
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Pulmonary arterial hypertension: epidemiology and registries.
J. Am. Coll. Cardiol.
PUBLISHED: 10-10-2013
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Registries of patients with pulmonary arterial hypertension (PAH) have been instrumental in characterizing the presentation and natural history of the disease and provide a basis for prognostication. Since the initial accumulation of data conducted in the 1980s, subsequent registry databases have yielded information about the demographic factors, treatment, and survival of patients and have permitted comparisons between populations in different eras and environments. Inclusion of patients with all subtypes of PAH has also allowed comparisons of these subpopulations. We describe herein the basic methodology by which PAH registries have been conducted, review key insights provided by registries, summarize issues related to interpretation and comparison of the results, and discuss the utility of data to predict survival outcomes. Potential sources of bias, particularly related to the inclusion of incident and/or prevalent patients and missing data, are addressed. A fundamental observation of current registries is that survival in the modern treatment era has improved compared with that observed previously and that outcomes among PAH subpopulations vary substantially. Continuing systematic clinical surveillance of PAH will be important as treatment evolves and as understanding of mechanisms advance. Considerations for future directions of registry studies include enrollment of a broader population of patients with pulmonary hypertension of all clinical types and severity and continued globalization and collaboration of registry databases.
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Anticoagulation and Survival in Pulmonary Arterial Hypertension: Results from the COMPERA Registry.
Circulation
PUBLISHED: 09-30-2013
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For almost 30 years, anticoagulation has been recommended for patients with idiopathic pulmonary arterial hypertension (IPAH). Supporting evidence, however, is limited, and it is unclear whether this recommendation is still justified in the modern management era and whether it should be extended to patients with other forms of pulmonary arterial hypertension (PAH).
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Inefficient exercise gas exchange identifies pulmonary hypertension in chronic thromboembolic obstruction following pulmonary embolism.
Thromb. Res.
PUBLISHED: 08-26-2013
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Persistent obstruction in the pulmonary artery following acute pulmonary embolism (PE) can give rise to both chronic thromboembolic pulmonary hypertension (CTEPH) and chronic thromboembolic disease without PH (CTED). We hypothesised that cardiopulmonary exercise testing (CPET) may be able to differentiate patients with CTEPH and CTED following unresolved PE which may help guide patient assessment.
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Decreased time constant of the pulmonary circulation in chronic thromboembolic pulmonary hypertension.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 05-17-2013
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This study analyzed the relationship between pulmonary vascular resistance (PVR) and pulmonary arterial compliance (Ca) in patients with idiopathic pulmonary arterial hypertension (IPAH) and proximal chronic thromboembolic pulmonary hypertension (CTEPH). It has recently been shown that the time constant of the pulmonary circulation (RC time constant), or PVR × Ca, remains unaltered in various forms and severities of pulmonary hypertension, with the exception of left heart failure. We reasoned that increased wave reflection in proximal CTEPH would be another cause of the decreased RC time constant. We conducted a retrospective analysis of invasive pulmonary hemodynamic measurements in IPAH (n = 78), proximal CTEPH (n = 91) before (pre) and after (post) pulmonary endarterectomy (PEA), and distal CTEPH (n = 53). Proximal CTEPH was defined by a postoperative mean pulmonary artery pressure (PAP) of ?25 mmHg. Outcome measures were the RC time constant, PVR, Ca, and relationship between systolic and mean PAPs. The RC time constant for pre-PEA CTEPH was 0.49 ± 0.11 s compared with post-PEA-CTEPH (0.37 ± 0.11 s, P < 0.0001), IPAH (0.63 ± 0.14 s, P < 0.001), and distal CTEPH (0.55 ± 0.12 s, P < 0.05). A shorter RC time constant was associated with a disproportionate decrease in systolic PAP with respect to mean PAP. We concluded that the pulmonary RC time constant is decreased in proximal CTEPH compared with IPAH, pre- and post-PEA, which may be explained by increased wave reflection but also, importantly, by persistent structural changes after the removal of proximal obstructions. A reduced RC time constant in CTEPH is in accord with a wider pulse pressure and hence greater right ventricular work for a given mean PAP.
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Supplementation of iron in pulmonary hypertension: Rationale and design of a phase II clinical trial in idiopathic pulmonary arterial hypertension.
Pulm Circ
PUBLISHED: 05-11-2013
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Our aim is to assess the safety and potential clinical benefit of intravenous iron (Ferinject) infusion in iron deficient patients with idiopathic pulmonary arterial hypertension (IPAH). Iron deficiency in the absence of anemia (1) is common in patients with IPAH; (2) is associated with inappropriately raised levels of hepcidin, the key regulator of iron homeostasis; and (3) correlates with disease severity and worse clinical outcomes. Oral iron absorption may be impeded by reduced absorption due to elevated hepcidin levels. The safety and benefits of parenteral iron replacement in IPAH are unknown. Supplementation of Iron in Pulmonary Hypertension (SIPHON) is a Phase II, multicenter, double-blind, randomized, placebo-controlled, crossover clinical trial of iron in IPAH. At least 60 patients will be randomized to intravenous ferric carboxymaltose (Ferinject) or saline placebo with a crossover point after 12 weeks of treatment. The primary outcome will be the change in resting pulmonary vascular resistance from baseline at 12 weeks, measured by cardiac catheterization. Secondary measures include resting and exercise hemodynamics and exercise performance from serial bicycle incremental and endurance cardiopulmonary exercise tests. Other secondary measurements include serum iron indices, 6-Minute Walk Distance, WHO functional class, quality of life score, N-terminal pro-brain natriuretic peptide (NT-proBNP), and cardiac anatomy and function from cardiac magnetic resonance. We propose that intravenous iron replacement will improve hemodynamics and clinical outcomes in IPAH. If the data supports a potentially useful therapeutic effect and suggest this drug is safe, the study will be used to power a Phase III study to address efficacy.
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Patient-reported outcomes assessed by the CAMPHOR questionnaire predict clinical deterioration in idiopathic pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.
Chest
PUBLISHED: 02-23-2013
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The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) is a disease-specific assessment tool used for the evaluation and follow-up of patients with pulmonary hypertension (PH). We describe a novel use for this questionnaire in its potential to predict clinical deterioration (CD) in two patient cohorts with subtypes of PH, idiopathic pulmonary arterial hypertension (IPAH), and chronic thromboembolic pulmonary hypertension (CTEPH) during an 8-year period.
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Chronic thromboembolic pulmonary hypertension: role of medical therapy.
Eur. Respir. J.
PUBLISHED: 02-08-2013
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Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease with poor prognosis if not treated. The treatment of choice is surgery with pulmonary endarterectomy. However, a significant percentage of patients are deemed non-operable due to distal distribution of the disease and arteriopathy in the non-occluded areas that is indistinguishable from pulmonary arterial hypertension (PAH). The overlap in clinical presentation, pathological features and pathogenesis between PAH and CTEPH provides a compelling rationale for exploring the efficacy of PAH-targeted therapies in CTEPH. These therapies are often considered for non-operable patients and are also used in operable patients as a bridge to surgery or as post-pulmonary endarterectomy therapy for persistent pulmonary hypertension, despite the fact they are not licensed for CTEPH. Two randomised clinical trials have been performed in non-operable CTEPH patients. The BENEFiT study, with the endothelin receptor antagonist bosentan, did not show improvement in walking distance. Recently, the CHEST-1 trial, with the soluble guanylate cyclase stimulator riociguat, met study end-point and demonstrated significant improvement in walking distance in patients with non-operable CTEPH. There is an urgent need for more randomised clinical trials designed to clarify whether administration of PAH-targeted therapies improves clinically meaningful end-points in various CTEPH populations.
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Factors associated with diagnosis and operability of chronic thromboembolic pulmonary hypertension. A case-control study.
Thromb. Haemost.
PUBLISHED: 02-04-2013
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Chronic thromboembolic pulmonary hypertension (CTEPH) and idiopathic pulmonary hypertension (IPAH) share a similar clinical presentation, and a differential diagnosis requires a thorough workup. Once CTEPH is confirmed, patients who can be safely operated have to be identified. We investigated risk factors associated with CTEPH and IPAH, and the criteria for the selection of operable CTEPH patients. This case-control study included 436 consecutive patients with CTEPH and 158 with IPAH in eight European centres, between 2006 and 2010. Conditions identified as risk factors for CTEPH included history of acute venous thromboembolism (p < 0.0001), large size of previous pulmonary embolism (p = 0.0040 in univariate analysis), blood groups non-O (p < 0.0001 in univariate analysis), and older age (p = 0.0198), whereas diabetes mellitus (p = 0.0006), female gender (p = 0.0197) and higher mean pulmonary artery pressure (p = 0.0103) were associated with increased likelihood for an IPAH diagnosis. Operability of CTEPH patients was associated with younger age (p = 0.0108), proximal lesions (p ? 0.0001), and pulmonary vascular resistance below 1200 dyn.s.cm?? (p = 0.0080). Non-operable CTEPH patients tended to be less differentiable from IPAH patients by risk factor analysis than operable patients. This study confirmed the association of CTEPH with history of acute venous thromboembolism and blood groups non-O, and identified diabetes mellitus and higher mean pulmonary artery pressure as factors suggesting an IPAH diagnosis. Non-operable CTEPH is more similar to IPAH than operable CTEPH regarding risk factors.
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(18)FDG PET imaging can quantify increased cellular metabolism in pulmonary arterial hypertension: A proof-of-principle study.
Pulm Circ
PUBLISHED: 12-30-2011
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The past decade has seen increased application of 18-flurodeoxyglucose positron emission tomography ((18)FDG-PET) imaging to help diagnose and monitor disease, particularly in oncology, vasculitis and atherosclerosis. Disordered glycolytic metabolism and infiltration of plexiform lesions by inflammatory cells has been described in idiopathic pulmonary arterial hypertension (IPAH). We hypothesized that increased (18)FDG uptake may be present in the lungs, large pulmonary arteries and right ventricle of patients with pulmonary hypertension, and that this uptake would be related to markers of immune activation. We imaged the thorax of 14 patients with pulmonary hypertension (idiopathic and chronic thromboembolic) and six controls by (18)FDG-PET/computed tomography (CT) and measured uptake in the lung parenchyma, large pulmonary arteries and right ventricle. (18)FDG uptake in the lungs and pulmonary arteries was normalized for venous blood activity to give a target-to-background ratio (TBR). Blood was contemporaneously drawn for high-sensitivity CRP - C-reactive protein (CRP) (hsCRP), N-Terminal Probrain natriuteric peptide (NT-ProBNP) and other inflammatory cytokines. IPAH patients had significantly higher lung parenchymal TBR (P=0.034) and right ventricle FDG uptake (P=0.007) than controls. Uptake in the main pulmonary arteries was similar in chronic thromboembolic pulmonary hypertension, IPAH and controls. There were no correlations between (18)FDG uptake and hsCRP or inflammatory cytokine levels. NT-ProBNP correlated with RV uptake in those with pulmonary hypertension (r=0.55, P=0.04). In this pilot study, we found increased (18)FDG uptake in the lung parenchyma and right ventricle of subjects with IPAH. The lung uptake might be useful as a surrogate marker of increased cellular metabolism and immune activation as underlying mechanisms in this disease. Further evaluation of the impact of targeted therapies in treatment-naïve patients and the significance of right ventricular uptake is suggested.
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Isolated large vessel pulmonary vasculitis as a cause of chronic obstruction of the pulmonary arteries.
Pulm Circ
PUBLISHED: 12-06-2011
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Isolated pulmonary artery involvement by large vessel vasculitis is rare. This case report describes two patients with large vessel pulmonary vasculitis initially thought to have chronic thromboembolic pulmonary hypertension who had their diagnosis revised following pulmonary endarterectomy surgery. Advances in imaging techniques such as positron emission tomography and magnetic resonance imaging have permitted complementary radiological methods of diagnosis and follow up of large vessel disease and these are discussed in conjunction with the immunosuppressive and operative management of these patients.
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Log-transformation improves the prognostic value of serial NT-proBNP levels in apparently stable pulmonary arterial hypertension.
Pulm Circ
PUBLISHED: 10-29-2011
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N-terminal pro B-type natriuretic peptide (NT-proBNP) is a product of cleavage of the cardiac prohormone pro B-type natriuretic peptide into its active form. It has proven to be a useful biomarker in left heart failure. However, studies examining the utility of serial measurements of NT-proBNP in pulmonary arterial hypertension (PAH) patients have shown mixed results. We compared three methods of predicting adverse clinical outcomes in PAH patients: the change in 6 minute walk distance (6MWD), the change in absolute levels of NT-proBNP and the change in log-transformed levels of NT-proBNP. All PAH patients presenting from March-June 2007 were screened. Patients who were clinically unstable, had abnormal renal function or hemoglobin levels or lacked a prior NT-proBNP were excluded. 63 patients were followed up for adverse clinical outcomes (defined as death, transplantation, hospitalisation for right heart failure, or need for increased therapy). Three methods were used to predict adverse events, i.e.: (a) comparing a 6MWD performed in March-June 2007 and a previous 6MWD. A decrease in 6MWD of ?30m was used to predict clinical deterioration; (b) comparing a NT-proBNP value measured in March-June 2007 and a previous NT-proBNP. An increase in NT-proBNP of ?250pg/ml was used to predict clinical deterioration (250pg/ml represented approximately 30% change from the baseline median value of NT-proBNP for this cohort); and (c) comparing the loge equivalents of two consecutive NT-proBNP values. We used the formula: loge(current NT-proBNP) - loge(previous NT-proBNP)=x. A value of x?+0.26 was used to predict adverse events. This is equivalent to a 30% change from baseline, and hence is comparable to the chosen cut-off for absolute levels of NT-proBNP. A loge difference of ?+0.26 identifies patients at risk of adverse events with a specificity of 98%, a sensitivity of 60%, a positive predictive value of 89%, and a negative predictive value of 90%. A drop in 6MWD of ?30m has a specificity of 29%, a sensitivity of 73%, a positive predictive value of 24% and a negative predictive value of 24%. It seems possible to risk-stratify apparently stable PAH patients by following the changes in their serial log-transformed NT-proBNP values. In this small pilot study, this method was better than relying on changes in the actual levels of NT-proBNP or changes in 6MWD. This needs to be validated prospectively in a larger cohort.
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Chronic thromboembolic pulmonary hypertension (CTEPH): results from an international prospective registry.
Circulation
PUBLISHED: 10-03-2011
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Chronic thromboembolic pulmonary hypertension (CTEPH) is often a sequel of venous thromboembolism with fatal natural history; however, many cases can be cured by pulmonary endarterectomy. The clinical characteristics and current management of patients enrolled in an international CTEPH registry was investigated.
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Pulmonary hypertension, nitric oxide and nitric oxide-releasing compounds.
Expert Rev Respir Med
PUBLISHED: 04-23-2011
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Nitric oxide (NO) is an important molecule in the mammalian cardiovascular system and the elucidation of its biological role has led to the awarding of a Nobel prize in medicine. There have been many significant discoveries in NO biology over the past two decades and translation of these developments from bench to bedside has allowed an explosion of therapies for pulmonary hypertension. This article provides an overview of the NO pathway in the pulmonary circulation in maintenance of normal vascular tone as well as its dysregulation in pulmonary hypertension, and a discussion of therapies based on inhaled NO or manipulation of its downstream signaling pathways. Several therapies such as phosphodiesterase inhibitors are already in use, and various experimental therapies are also discussed.
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Dual-energy CT angiography for assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension: initial experience.
AJR Am J Roentgenol
PUBLISHED: 02-24-2011
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This study assessed the utility of dual-energy pulmonary CT angiography (CTA) for noninvasive assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Regional perfusion abnormalities were correlated with hemodynamic parameters and structural abnormalities on pulmonary CTA.
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Surgical management and outcome of patients with chronic thromboembolic pulmonary hypertension: results from an international prospective registry.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 02-22-2011
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Pulmonary endarterectomy is a curative surgical treatment option for the majority of patients with chronic thromboembolic pulmonary hypertension. The current surgical management and postoperative outcome of patients enrolled in an international registry on chronic thromboembolic pulmonary hypertension were investigated.
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Unexplained iron deficiency in idiopathic and heritable pulmonary arterial hypertension.
Thorax
PUBLISHED: 02-05-2011
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Anaemia is common in left heart failure and is associated with a poorer outcome. Many patients with pulmonary arterial hypertension (PAH) are anaemic or iron-deficient. This study was performed to investigate the prevalence of iron deficiency in PAH and to identify possible causes.
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Elevated levels of inflammatory cytokines predict survival in idiopathic and familial pulmonary arterial hypertension.
Circulation
PUBLISHED: 08-16-2010
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Inflammation is a feature of pulmonary arterial hypertension (PAH), and increased circulating levels of cytokines are reported in patients with PAH. However, to date, no information exists on the significance of elevated cytokines or their potential as biomarkers. We sought to determine the levels of a range of cytokines in PAH and to examine their impact on survival and relationship to hemodynamic indexes.
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Survival after pulmonary thromboendarterectomy: effect of residual pulmonary hypertension.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 05-13-2010
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Pulmonary endarterectomy is the treatment of choice for chronic thromboembolic pulmonary hypertension. In many patients hemodynamics are normalized early after surgical intervention. However, the effect of residual pulmonary hypertension on postoperative clinical status and survival is unknown.
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Pulmonary arterial size and response to sildenafil in chronic thromboembolic pulmonary hypertension.
J. Heart Lung Transplant.
PUBLISHED: 03-15-2010
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Relative area change (RAC) of the proximal pulmonary artery is a measurement of pulmonary artery distensibility and has been shown to correlate with vasoreactivity studies in patients with idiopathic pulmonary arterial hypertension. We have previously noted a relationship between invasive hemodynamic vasoreactivity testing and long-term response to sildenafil in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). We therefore set out to determine whether RAC can provide useful correlatory non-invasive data.
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Intravenous epoprostenol versus high dose inhaled iloprost for long-term treatment of pulmonary hypertension.
Pulm Pharmacol Ther
PUBLISHED: 02-18-2010
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Intravenous prostacyclin (iv PGI) and inhaled Iloprost (inh ilo) are established therapies in pulmonary arterial hypertension (PAH), however comparative data are lacking.
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Tadalafil therapy and health-related quality of life in pulmonary arterial hypertension.
Curr Med Res Opin
PUBLISHED: 08-19-2009
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Pulmonary arterial hypertension (PAH) is a rare, progressive lung disorder that impairs performance of daily activities and quality of life (QoL), leading to right heart failure and death. Treatment options include prostanoids, endothelin antagonists, and phosphodiesterase type 5 inhibitors (e.g., tadalafil). Currently there is no cure for PAH, but tadalafil has improved exercise capacity in these patients.
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Evidence of dysfunction of endothelial progenitors in pulmonary arterial hypertension.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 07-23-2009
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Severe pulmonary arterial hypertension (PAH) is characterized by the formation of plexiform lesions and concentric intimal fibrosis in small pulmonary arteries. The origin of cells contributing to these vascular lesions is uncertain. Endogenous endothelial progenitor cells are potential contributors to this process.
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Interventional and surgical modalities of treatment in pulmonary hypertension.
J. Am. Coll. Cardiol.
PUBLISHED: 04-13-2009
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Most patients with chronic thromboembolic pulmonary hypertension are operable, and pulmonary endarterectomy is the treatment of choice. Pulmonary endarterectomy should not be delayed for medical therapy, and risk stratification helps to define patients likely to achieve the best outcome. Inoperable patients should be referred for trials of medical agents. Atrial septostomy is promising but underutilized, although better ways of ensuring an adequate, lasting septostomy still need to be determined. Indications for the procedure are unchanged, and it should be considered more frequently. Bilateral sequential lung or heart-lung transplantation is an important option for selected patients, and potential candidates who are class IV or III but not improving should be referred early to a transplantation center. Currently, there is a need for right ventricular assist devices with flow characteristics suited to the circulation of patients with pulmonary arterial hypertension. Right ventricular synchronization therapy has not yet been tested. Novel shunts (e.g., Potts anastomosis) also hold promise. All surgery for pulmonary hypertension should be performed in centers with experience in these techniques.
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Diagnosis, assessment, and treatment of non-pulmonary arterial hypertension pulmonary hypertension.
J. Am. Coll. Cardiol.
PUBLISHED: 02-06-2009
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The 4th World Symposium on Pulmonary Hypertension was the first international meeting to focus not only on pulmonary arterial hypertension (PAH) but also on the so-called non-PAH forms of pulmonary hypertension (PH). The term "non-PAH PH" summarizes those forms of PH that are found in groups 2 to 5 of the current classification of PH, that is, those forms associated with left heart disease, chronic lung disease, recurrent venous thromboembolism, and other diseases. Many of these forms of PH are much more common than PAH, but all of them have been less well studied, especially in terms of medical therapy. The working group on non-PAH PH focused mainly on 4 conditions: chronic obstructive lung disease, interstitial lung disease, chronic thromboembolic PH, and left heart disease. The medical literature regarding the role of PH in these diseases was reviewed, and recommendations regarding diagnosis and treatment of PH in these conditions are provided. Given the lack of robust clinical trials addressing PH in any of these conditions, it is important to conduct further studies to establish the role of medical therapy in non-PAH PH.
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Connective tissue disease-associated pulmonary arterial hypertension in the modern treatment era.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 01-24-2009
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Pulmonary arterial hypertension in association with connective tissue disease (CTD-PAH) has historically had a poor prognosis, with a 1-year survival rate among patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) of 45%. However, more therapies have become available.
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Impaired natural killer cell phenotype and function in idiopathic and heritable pulmonary arterial hypertension.
Circulation
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Beyond their role as innate immune effectors, natural killer (NK) cells are emerging as important regulators of angiogenesis and vascular remodeling. Pulmonary arterial hypertension (PAH) is characterized by severe pulmonary vascular remodeling and has long been associated with immune dysfunction. Despite this association, a role for NK cells in disease pathology has not yet been described.
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Pulmonary endarterectomy: outcomes in patients aged >70.
Eur J Cardiothorac Surg
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Advanced age is not a barrier to cardiac surgery, with reports demonstrating excellent outcomes, but the effect of age on more complex surgery has not been studied. We assessed the outcomes of pulmonary endarterectomy (PEA) surgery in patients aged >70.
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Serum osteoprotegerin is increased and predicts survival in idiopathic pulmonary arterial hypertension.
Pulm Circ
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We previously reported that osteoprotegerin (OPG) is regulated by pathways associated with pulmonary arterial hypertension (PAH), and is present at elevated levels within pulmonary vascular lesions and sera from patients with idiopathic PAH (IPAH). Since OPG is a naturally secreted protein, we investigated the relationship between serum OPG and disease severity and outcome in patients with IPAH and animal models. OPG mRNA expression was measured in pulmonary artery smooth muscle cells (PASMC) from pulmonary arteries of patients with and without IPAH. Serum concentrations of OPG were measured in a retrospective and prospective group of patients. OPG levels were compared with phenotypic data and other putative PAH biomarkers. Prognostic significance was assessed and levels compared with healthy controls. Correlation of OPG and pulmonary vascular remodeling was also performed in rodent models of PAH. OPG mRNA was significantly increased 2-fold in PASMC isolated from explanted PAH lungs compared with control. Serum OPG concentrations were markedly elevated in IPAH compared with controls. In Cohort 1 OPG levels significantly correlated with mean right atrial pressure and cardiac index, while in Cohort 2 significant correlations existed between age-adjusted OPG levels and gas transfer. In both cohorts an OPG concentration above a ROC-derived threshold of 4728 pg/ml predicted poorer survival. In two rodent models, OPG correlated with the degree of pulmonary vascular remodeling. OPG levels are significantly elevated in patients with idiopathic PAH and are of prognostic significance. The role of OPG as a potential biomarker and therapeutic target merits further investigation.
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Predicting survival in pulmonary arterial hypertension in the UK.
Eur. Respir. J.
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Contemporary prognostic equations in pulmonary arterial hypertension (PAH) derived from US and French cohorts may not perform as well in the UK as a locally derived scoring scheme. The aim of the study was to develop and validate a UK risk score to predict prognosis in PAH. Baseline mortality predictors identified by multivariate Cox analysis in 182 incident PAH patients were used to derive the Scottish composite score (SCS). Its prognostic performance in an independent UK cohort was compared with the French registry and Pulmonary Hypertension Connection (PHC) registry equations using Brier scores (BS). The SCS based on age, sex, aetiology, right atrial pressure, cardiac output and 6-min walk distance predicted survival in the validation cohort (hazard ratio (HR) 1.7 per point increase; p<0.001) and provided further prognostic stratification in World Health Organization (WHO) functional class III patients (HR 1.8 per point increase; p<0.001). It was more accurate than the French registry equation in predicting 1-yr survival (BS: 0.092 versus 0.146; p=0.001) and 2-yr survival (0.131 versus 0.255; p<0.001). There was no significant difference in BS between the SCS and PHC registry equation. The SCS predicts survival and can be used to supplement WHO functional class in prognostication.
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Occlusion pressure analysis role in partitioning of pulmonary vascular resistance in CTEPH.
Eur. Respir. J.
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Flow-directed pulmonary artery occlusion is posited to enable partitioning of vascular resistance into small and large vessels. As such it may have a role in assessment for pulmonary endarterectomy. To test if the occlusion technique distinguished small from large vessel disease we studied 59 subjects with chronic thromboembolic pulmonary hypertension (CTEPH), idiopathic pulmonary arterial hypertension (IPAH), and connective tissue disease (CTD)-associated PAH. At right heart catheterisation, occlusion pressures were recorded. With fitting of the pressure decay curve, pulmonary vascular resistance was partitioned into downstream (small vessels) and upstream (large vessels, Rup). 47 patients completed the study; 14 operable CTEPH, 15 inoperable CTEPH, 13 idiopathic or CTD-PAH and five post-operative CTEPH. There was a significant difference in mean Rup in the proximal operable CTEPH group 87.3 (95% CI 84.1-90.5); inoperable CTEPH mean 75.8 (95% CI 66.76-84.73), p=0.048; and IPAH/CTD, mean 77.1 (95% CI 71.86-82.33), p=0.003. Receiver operating characteristic curves to distinguish operable from inoperable CTEPH demonstrated an area under the curve of 0.75, p=0.0001. A cut-off of 79.3 gave 100% sensitivity (95% CI 73.5-100%) but 57.1% specificity (95% CI 28.9-82.3%). In a subgroup analysis of multiple lobar sampling there was demonstrable heterogeneity. Rup is significantly increased in operable proximal CTEPH compared with non-operable distal CTEPH and IPAH/CTD-PAH. Rup variability in patients with CTEPH and PAH is suggestive of pathophysiological heterogeneity.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.