***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: Objective Decision making for intervention in symptomatic aortic stenosis should balance the risks of surgery and of transcatheter aortic valve implantation ( TAVI ) . We identified the factors associated with early mortality after TAVI and aim ed to develop and vali date a simple risk score . Methods A population of 3833 consecutive patients was r and omly split into two cohorts comprising 2552 and 1281 patients , used respectively to develop and vali date a scoring system predicting 30-day or in-hospital mortality . Results TAVI was performed using the Edwards Sapien prosthesis in 2551 ( 66.8 % ) patients and the Medtronic Corevalve in 1270 ( 33.2 % ) . Approach was transfemoral in 2801 ( 73.4 % ) patients , transapical in 678 ( 17.8 % ) , subclavian in 219 ( 5.7 % ) and other in 117 ( 3.1 % ) . Early mortality was 10.0 % ( 382 patients ) . A multivariate logistic model identified the following predictive factors of early mortality : age ≥90 years , body mass index < 30 Kg/m2 , New York Heart Association class IV , pulmonary hypertension , critical haemodynamic state , ≥2 pulmonary oedemas during the last year , respiratory insufficiency , dialysis and transapical or other ( transaortic and transcarotid ) approaches . A 21-point predictive score was derived . C-index was 0.67 for the score in the development cohort and 0.59 in the validation cohort . There was a good concordance between predicted and observed 30-day mortality rates in the development and validation cohorts . Conclusions Early mortality  after TAVI is mainly related to age , the severity of symptoms , comorbidities and transapical approach . A simple score can be used to predict early mortality  after TAVI . The moderate discrimination is however a limitation for the accurate identification of high-risk patients OBJECTIVES This study sought to assess the impact of baseline left ventricular ( LV ) outflow , LV ejection fraction ( LVEF ) , and transvalvular gradient on outcomes following transcatheter aortic valve replacement ( TAVR ) in patients with severe aortic stenosis ( AS ) . BACKGROUND Low flow ( i.e. , reduced stroke volume index [ SVi ] ) can occur with both reduced and preserved LVEF . Low flow is often associated with low gradient despite severe stenosis and with worse outcomes following surgical aortic valve replacement . However , there are few data about the impact of low flow on outcomes following TAVR . METHODS We retrospectively analyzed the clinical , Doppler-echocardiographic , and outcome data prospect ively collected in 639 patients who underwent TAVR for symptomatic severe AS in 2 Canadian centers . RESULTS In this cohort , 334 ( 52.3 % ) patients had a low flow ( SVi < 35 ml/m(2 ) ) and these patients had increased 30-day mortality ( 11.4 vs. 5.9 % , p = 0.01 ) , 2-year all-cause mortality ( 35.3 vs. 30.9 % , p = 0.005 ) , and 2-year cardiovascular mortality ( 25.7 vs. 16.8 % , p = 0.01 ) compared with patients with normal flow . Reduced flow was an independent predictor of 30-day mortality ( odds ratio : 1.94 , p = 0.026 ) , cumulative all-cause mortality ( hazard ratio : 1.27 per 10 ml/m(2 ) SVi decrease , p = 0.016 ) , and cumulative cardiovascular mortality ( hazard ratio : 1.29 per 10 ml/m(2 ) decrease , p = 0.04 ) . Despite significant association in univariable analyses , low LVEF and low mean gradient were not found to be independent predictors of outcomes in multivariable analyses . CONCLUSIONS Low flow but not low LVEF or low gradient is an independent predictor of early and late mortality following TAVR in high-risk patients with severe AS . SVi should be integrated in the risk stratification process of these patients OBJECTIVES The objective was to define the characteristics of a real-world patient population treated with transcatheter aortic valve implantation ( TAVI )  , regardless of technology or access route , and to evaluate their clinical outcome over the mid to long term . BACKGROUND Although a substantial body of data exists in relation to early clinical outcomes after TAVI , there are few data on outcomes beyond 1 year in any notable number of patients . METHODS The U.K. TAVI ( United Kingdom Transcatheter Aortic Valve Implantation ) Registry was established to report outcomes of all TAVI procedures performed within the United Kingdom . Data were collected prospect ively on 870 patients undergoing 877 TAVI procedures up until December 31 , 2009 . Mortality tracking was achieved in 100 % of patients with mortality status reported as of December 2010 . RESULTS Survival at 30 days was 92.9 % , and it was 78.6 % and 73.7 % at 1 year and 2 years , respectively . There was a marked attrition in survival between 30 days and 1 year . In a univariate model , survival was significantly adversely affected by renal dysfunction , the presence of coronary artery disease , and a nontransfemoral approach ; whereas left ventricular function ( ejection fraction < 30 % ) , the presence of moderate/severe aortic regurgitation , and chronic obstructive pulmonary disease remained the only independent predictors of mortality in the multivariate model . CONCLUSIONS Midterm to long-term survival after TAVI was encouraging in this high-risk patient population , although a substantial proportion of patients died within the first year OBJECTIVES The aim of this study was : 1 ) to evaluate the acute and late outcomes of a transcatheter aortic valve implantation ( TAVI ) program including both the transfemoral ( TF ) and transapical ( TA ) approaches ; and 2 ) to determine the results of TAVI  in patients deemed inoperable because of either porcelain aorta or frailty . BACKGROUND Very few data exist on the results of a comprehensive TAVI program including both TA and TF approaches for the treatment of severe aortic stenosis in patients at very high or prohibitive surgical risk . METHODS Consecutive patients who underwent TAVI with the Edwards valve ( Edwards Lifesciences , Inc. , Irvine , California ) between January 2005 and June 2009 in 6 Canadian centers were included . RESULTS A total of 345 procedures ( TF : 168 , TA : 177 ) were performed in 339 patients . The predicted surgical mortality ( Society of Thoracic Surgeons risk score ) was 9.8 + /- 6.4 % . The procedural success rate was 93.3 % , and 30-day mortality was 10.4 % ( TF : 9.5 % , TA : 11.3 % ) . After a median follow-up of 8 months ( 25th to 75th interquartile range : 3 to 14 months ) the mortality rate was 22.1 % . The predictors of cumulative late mortality were peri-procedural sepsis ( hazard ratio [ HR ] : 3.49 , 95 % confidence interval [ CI ] : 1.48 to 8.28 ) or need for hemodynamic support ( HR : 2.58 , 95 % CI : 1.11 to 6 ) , pulmonary hypertension ( PH ) ( HR : 1.88 , 95 % CI : 1.17 to 3 ) , chronic kidney disease ( CKD ) ( HR : 2.30 , 95 % CI : 1.38 to 3.84 ) , and chronic obstructive pulmonary disease ( COPD ) ( HR : 1.75 , 95 % CI : 1.09 to 2.83 ) . Patients with either porcelain aorta ( 18 % ) or frailty ( 25 % ) exhibited acute outcomes similar to the rest of the study population , and porcelain aorta patients tended to have a better survival rate at 1-year follow-up . CONCLUSIONS A TAVI program including both TF and TA approaches was associated with comparable mortality as predicted by surgical risk calculators for the treatment of patients at very high or prohibitive surgical risk , including porcelain aorta and frail patients . Baseline ( PH , COPD , CKD ) and peri-procedural ( hemodynamic support , sepsis ) factors but not the approach determined worse outcomes Pulmonary hypertension ( PH ) is prevalent in patients with aortic stenosis ( AS ) ; however , previous studies have demonstrated inconsistent results regarding the association of PH with adverse outcomes after  aortic valve replacement ( AVR ) . The goal of this study was to evaluate the effects of preoperative PH on outcomes after AVR . We performed a regional prospect i ve cohort study using the Northern New Engl and Cardiovascular Disease Study Group data base to identify 1,116 consecutive patients from 2005 to 2010 who underwent AVR ± coronary artery bypass grafting for severe AS with a preoperative assessment of pulmonary pressures by right-sided cardiac catheterization .  PH was defined as a mean pulmonary artery pressure of ≥25 mm Hg , with severity based on the pulmonary artery systolic pressure-mild , 35 to 44 mm Hg ; moderate , 45 to 59 mm Hg ; and severe , ≥60 mm Hg . We found that PH was present in 536 patients ( 48 % ) . Postoperative acute kidney injury , low-output heart failure , and in-hospital mortality increased with worsening severity of PH . In multivariate logistic regression , severe PH was independently associated with postoperative acute kidney injury ( adjusted odds ratio 4.1 , 95 % confidence interval [ CI ] 1.7 to 10 , p = 0.002 ) and in-hospital mortality ( adjusted odds ratio 6.9 , 95 % CI 2.5 to 19.1 , p < 0.001 ) . There was a significant association between PH and decreased 5-year survival ( adjusted log-rank p value = 0.006 ) , with severe PH being associated with the poorest survival ( adjusted hazard ratio 2.4 , 95 % CI 1.3 to 4.2 , p = 0.003 ) . In conclusion , severe PH in patients with severe AS is associated with increased rates of in-hospital adverse events and decreased 5-year survival after AVR BACKGROUND The Placement of Aortic Transcatheter Valves ( PARTNER ) trial showed that mortality at 1 year , 2 years , and 3 years is much the same with transcatheter aortic valve replacement ( TAVR ) or surgical aortic valve replacement ( SAVR ) for high-risk patients with aortic stenosis . We report here the 5-year outcomes . METHODS We did this r and omised controlled trial at 25 hospitals , in Canada ( two ) , Germany ( one ) , and the USA ( 23 ) . We used a computer-generated r and omisation sequence to r and omly assign high-risk patients with severe aortic stenosis to either SAVR or TAVR with a balloon-exp and able bovine pericardial tissue valve by either a transfemoral or transapical approach . Patients and their treating physicians were not masked to treatment allocation . The primary outcome of the trial was all-cause mortality in the intention-to-treat population at 1 year , we present here predefined outcomes at 5 years . The study is registered with Clinical Trials.gov , number NCT00530894 . FINDINGS We screened 3105 patients , of whom 699 were enrolled ( 348 assigned to TAVR , 351 assigned to SAVR ) . Overall mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 11·7 % . At 5 years , risk of death was 67·8 % in the TAVR group compared with 62·4 % in the SAVR group ( hazard ratio 1·04 , 95 % CI 0·86 - 1·24 ; p=0·76 ) . We recorded no structural valve deterioration requiring surgical valve replacement in either group . Moderate or severe aortic regurgitation occurred in 40 ( 14 % ) of 280 patients in the TAVR group and two ( 1 % ) of 228 in the SAVR group ( p<0·0001 ) , and was associated with increased 5-year risk of mortality  in the TAVR group ( 72·4 % for moderate or severe aortic regurgitation vs 56·6 % for those with mild aortic regurgitation or less ; p=0·003 ) . INTERPRETATION Our findings show that TAVR as an alternative to surgery for patients with high surgical risk results in similar clinical outcomes . FUNDING Edwards Lifesciences IMPORTANCE Introducing new medical devices into routine practice raises concerns because patients and outcomes may differ from those in r and omized trials . OBJECTIVE To up date the previous report of 30-day outcomes and present 1-year outcomes following  transcatheter a 
    Output:
    
COPD is common among patients undergoing TAVI  , and COPD impacts both short- and long-term survival .
COPD patients , who had a lower BMI , shorter distance of 6MWT and CKD , were at higher risk for TAVI futility