***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Abstract Purpose Exercise training as an add-on to medical therapy has been shown to improve exercise capacity , quality of life , and possibly prognosis in patients with pulmonary hypertension ( PH ) . The purpose of this study was to analyze the impact of exercise training on healthcare costs in PH . Methods Estimated healthcare costs have been compared between patients with severe PH under optimized medical therapy only ( control group ) versus patients who received exercise training as an add-on to medical therapy ( training group ) . Cost- analysis included a cost-estimation model of costs for baseline and follow-up visits and all PH-related healthcare events that occurred within the follow-up period . Time to clinical worsening and survival were assessed by clinical records , phone , and /or control visits . Results At baseline , the training ( n = 58 ) and control group ( n = 48 ) did not differ in age , gender , WHO-functional class , 6-min walking distance , hemodynamic parameters , or PH-targeted medication . During a follow-up of 24 ± 12 months , the training group had significantly better survival rates at 1 and 3 years and less worsening events ( death , lung transplantation , hospitalization due to PH , new PAH-targeted medication ) than the control group ( 15 vs. 25 events , p < 0.05 ) , which also led to lower estimated healthcare costs of 657 € within a period of 2 years . Conclusions This is the first study to investigate the cost-effectiveness  of exercise training  in PH . Due to less worsening events within 2 years , healthcare costs were lower in patients performing exercise training as add-on to medical therapy than in patients with medical treatment only . Further prospect i ve , r and omized studies are needed to confirm these findings Abstract Objectives To evaluate whether careful exercise training improves pulmonary perfusion and blood flow in patients with pulmonary hypertension ( PH ) , as assessed by magnetic resonance imaging ( MR ) . Methods Twenty patients with pulmonary arterial hypertension or inoperable chronic thromboembolic PH on stable medication were r and omly assigned to control ( n = 10 ) or training groups ( n = 10 ) . Training group patients received in-hospital exercise training ; patients of the  sedentary control group  received conventional rehabilitation . Medication remained unchanged during the study period . Changes of 6-min walking distance ( 6MWD ) , MR pulmonary flow ( peak velocity ) and MR perfusion ( pulmonary blood volume ) were assessed from baseline to week 3 . Results After 3 weeks of training , increases in mean 6MWD ( P = 0.004 ) and mean MR flow peak velocity ( P = 0.012 ) were significantly greater in the training group . Training group patients had significantly improved 6MWD ( P = 0.008 ) , MR flow ( peak velocity −9.7 ± 8.6 cm/s , P = 0.007 ) and MR perfusion ( pulmonary blood volume + 2.2 ± 2.7 mL/100 mL , P = 0.017 ) , whereas the control group showed no significant changes . Conclusion The study indicates that respiratory and physical exercise may improve pulmonary perfusion in patients with PH . Measurement of MR parameters of pulmonary perfusion might be an interesting new method to assess therapy effects in PH . The results of this initial study should be confirmed in a larger study group . Key Points• Quantification of magnetic resonance perfusion is feasible in patients with pulmonary hypertension . • Quantified magnetic resonance perfusion may become useful for non-invasive monitoring of treatment . • Quantification of lung perfusion allows new insights into lung (patho-)physiology of PH . • Careful exercise training  improves pulmonary perfusion and blood flow in patients with PH Background — Pulmonary hypertension ( PH ) is associated with restricted physical capacity , limited quality of life , and a poor prognosis because of right heart failure . The present study is the first prospect i ve r and omized study to evaluate the effects of exercise and respiratory training in patients with severe symptomatic PH . Methods and Results — Thirty patients with PH ( 21 women ; mean age , 50±13 years ; mean pulmonary artery pressure , 50±15 mm Hg ; mean World Health Organization [ WHO ] class , 2.9±0.5 ; pulmonary arterial hypertension , n=23 ; chronic thromboembolic PH , n=7 ) on stable disease-targeted medication were r and omly assigned to a control ( n=15 ) and a primary training ( n=15 ) group . Medication remained unchanged during the study period . Primary end points were the changes from baseline to week 15 in the distance walked in 6 minutes and in scores of the Short Form Health Survey quality -of-life question naire . Changes in WHO functional class , Borg scale , and parameters of echocardiography and gas exchange also were assessed . At week 15 , patients in the primary and secondary training groups had an improved 6-minute walking distance ; the mean difference between the control and the primary training group was 111 m ( 95 % confidence interval , 65 to 139 m ; P<0.001 ) . Exercise training was well tolerated and improved scores of quality of life , WHO functional class , peak oxygen consumption , oxygen consumption at the anaerobic threshold , and achieved workload . Systolic pulmonary artery pressure values at rest did not change significantly after 15 weeks of exercise and respiratory training ( from 61±18 to 54±18 mm Hg ) within the training group . Conclusions — This study indicates that respiratory and physical training could be a promising adjunct to medical treatment in severe PH . The effects add to the beneficial results of modern medical treatment Background — Factors that determine survival in pulmonary arterial hypertension ( PAH ) drive clinical management . A quantitative survival prediction tool has not been established for research or clinical use . Methods and Results — Data from 2716 patients with PAH enrolled consecutively in the US Registry to Evaluate Early and Long-Term PAH Disease Management ( REVEAL ) were analyzed to assess predictors of 1-year survival . We identified independent prognosticators of survival and derived a multivariable , weighted risk formula for clinical use . One-year survival from the date of enrollment was 91.0 % ( 95 % confidence interval [ CI ] , 89.9 to 92.1 ) . In a multivariable analysis with Cox proportional hazards , variables independently associated with increased mortality included pulmonary vascular resistance > 32 Wood units ( hazard ratio [ HR ] , 4.1 ; 95 % CI , 2.0 to 8.3 ) , PAH associated with portal hypertension ( HR , 3.6 ; 95 % CI , 2.4 to 5.4 ) , modified New York Heart Association/World Health Organization functional class IV ( HR , 3.1 ; 95 % CI , 2.2 to 4.4 ) , men > 60 years of age ( HR , 2.2 ; 95 % CI , 1.6 to 3.0 ) , and family history of PAH ( HR , 2.2 ; 95 % CI , 1.2 to 4.0 ) . Renal insufficiency , PAH associated with connective tissue disease , functional class III , mean right atrial pressure , resting systolic blood pressure and heart rate , 6-minute walk distance , brain natriuretic peptide , percent predicted carbon monoxide diffusing capacity , and pericardial effusion on echocardiogram all predicted mortality . Based on these multivariable analyses , a prognostic equation was derived and vali date d by bootstrapping technique . Conclusions — We identified key predictors of survival based on the patient 's most recent evaluation and formulated a contemporary prognostic equation . Use of this tool may allow the individualization and optimization of therapeutic strategies . Serial follow-up and re assessment are warranted . Clinical Trial Registration — URL : http://www . clinical trials.gov . Unique identifier : NCT00370214 OBJECTIVE To characterize mortality in persons diagnosed with primary pulmonary hypertension and to investigate factors associated with survival . DESIGN Registry with prospect i ve follow-up . SETTING Thirty-two clinical centers in the United States participating in the Patient Registry for the Characterization of Primary Pulmonary Hypertension supported by the National Heart , Lung , and Blood Institute . PATIENTS Patients ( 194 ) diagnosed at clinical centers between 1 July 1981 and 31 December 1985 and followed through 8 August 1988 . MEASUREMENTS At diagnosis , measurements of hemodynamic variables , pulmonary function , and gas exchange variables were taken in addition to information on demographic variables , medical history , and life-style . Patients were followed for survival at 6-month intervals . MAIN RESULTS The estimated median survival of these patients was 2.8 years ( 95 % Cl , 1.9 to 3.7 years ) . Estimated single-year survival rates were as follows : at 1 year , 68 % ( Cl , 61 % to 75 % ) ; at 3 years , 48 % ( Cl , 41 % to 55 % ) ; and at 5 years , 34 % ( Cl , 24 % to 44 % ) . Variables associated with poor survival included a New York Heart Association ( NYHA ) functional class of III or IV , presence of Raynaud phenomenon , elevated mean right atrial pressure , elevated mean pulmonary artery pressure , decreased cardiac index , and decreased diffusing capacity for carbon monoxide ( DLCO ) . Drug therapy at entry or discharge was not associated with survival duration . CONCLUSIONS Mortality was most closely associated with right ventricular hemodynamic function and can be characterized by means of an equation using three variables : mean pulmonary artery pressure , mean right atrial pressure , and cardiac index . Such an equation , once vali date d prospect ively , could be used as an adjunct in planning treatment strategies and allocating medical re sources Background Advances in the underst and ing and management of pulmonary arterial hypertension have enabled earlier diagnosis and improved prognosis . However , despite best available therapy , symptoms of exertional dyspnoea and fatigue are commonly reported and result in a reduced capacity to perform daily activities and impaired quality of life . Exercise training has demonstrated efficacy in individuals with other respiratory and cardiovascular diseases . Historically , however , exercise training has not been utilised as a form of therapy in pulmonary arterial hypertension due to the perceived risk of sudden cardiac death and the theoretical possibility that exercise would lead to worsening pulmonary vascular haemodynamics and deterioration in right heart function . Now , with the advances in pharmaceutical management , determining the safety and benefits of exercise training in this population has become more relevant . Only three studies of supervised exercise training in pulmonary arterial hypertension have been published . These studies demonstrated improvements in exercise capacity and quality of life , in the absence of adverse events or clinical deterioration . However , these studies have not utilised an outpatient-based , whole body exercise training program , the most common format for exercise programs within Australia . It is uncertain whether this form of training is beneficial and capable of producing sustained benefits in exercise capacity and quality of life in this population . Design / Methods This r and omised controlled trial will determine whether a 12 week , outpatient-based , supervised , whole body exercise training program , followed by a home-based exercise program , is safe and improves exercise capacity and quality of life in individuals with pulmonary arterial hypertension . This study aims to recruit 34 subjects who will be r and omly allocated to the exercise group ( supervised exercise training 3 times a week for 12 weeks , followed by 3 sessions per week of home exercise for 12 weeks ) or the  control group ( usual medical care ) . Subjects will be assessed at baseline , 12 weeks and 24 weeks . Discussion This study will determine whether outpatient-based , whole body exercise training is beneficial and safe in individuals with pulmonary arterial hypertension . Additionally , this study will contribute to clinical practice guidelines for this patient population .Trial registration Australia and New Zeal and Clinical Trials Register ( ANZCTR ) : The CONSORT ( Consoli date d St and ards of Reporting Trials ) statement is used worldwide to improve the reporting of r and omized , controlled trials . Schulz and colleagues describe the latest version , CONSORT 2010 , which up date s the reporting guideline based on new method ological evidence and accumulating experience . Background Aim of this prospect i ve study was to evaluate the effects of exercise training in patients with inoperable or residual chronic thromboembolic pulmonary hypertension ( CTEPH ) . Methods Thirty-five consecutive patients with invasively confirmed inoperable or residual CTEPH ( 16 women;19 men ; mean age 61±15 years , mean pulmonary artery pressure , 63±20 mmHg ; primary inoperable n = 33 , persisting pulmonary hypertension after pulmonary endarterectomy n = 2 ) on stable disease-targeted medication received exercise training in-hospital for 3 weeks and continued at home for 15 weeks . Medication remained unchanged during the study period . Efficacy parameters have been evaluated at baseline , after 3 and 15 weeks by blinded-observers . Survival rate has been evaluated in a follow-up period of median 36.4 months ( interquartile range 26.6–46.6 months ) . Results All patients tolerated exercise training without severe adverse events . Patients significantly improved the mean distance walked in 6 minutes compared to baseline by 61±54 meters after 3 weeks ( p<0.001 ) and by 71±70 meters after 15 weeks ( p = 0.001 ) , as well as scores of quality -of-life question naire , peak oxygen consumption and maximal workload . NT-proBNP improved significantly after 3 weeks of exercise training ( p = 0.046 ) . The 1-year survival rate was 97 % , 2 
    Output:
    
In people with PH , exercise-based rehabilitation results in clinical ly relevant improvements in exercise capacity .
Exercise training was not associated with any serious adverse events .
Whilst most studies reported improvements in HRQoL , these may not be clinical ly important .