***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 
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    Input: Background Percutaneous mitral valve repair ( MVR ) using the MitraClip system has become a valid alternative for patients with severe mitral regurgitation ( MR ) and high operative risk . Objective To identify clinical and periprocedural factors that may have an impact on clinical outcome . Design Multi-centre longitudinal cohort study . Setting Tertiary referral centres . Patients Here we report on the first 100 consecutive patients treated with percutaneous MVR in Switzerl and between March 2009 and April 2011 . All of them had moderate – severe ( 3 + ) or severe ( 4 + ) MR , and 62 % had functional MR . 82 % of the patients were in New York Heart Association ( NYHA ) class III/IV , mean left ventricular ejection fraction was 48 % and the median European System for Cardiac Operative Risk Evaluation was 16.9 % . Interventions MitraClip implantation performed under echocardiographic and fluoroscopic guidance in general anaesthesia . Main outcome measures Clinical , echocardiographic and procedural data were prospect ively collected . Results Acute procedural success ( APS , defined as successful clip implantation with residual MR grade ≤2 + ) was achieved in 85 % of patients . Overall survival at 6 and 12 months was 89.9 % ( 95 % CI 81.8 to 94.6 ) and 84.6 % ( 95 % CI 74.7 to 91.0 ) , respectively . Univariate Cox regression analysis identified APS ( p=0.0069 ) and discharge MR grade ( p=0.03 ) as significant predictors of survival . Conclusions In our consecutive cohort of patients , APS was achieved in 85 % . APS and residual discharge MR grade are important predictors of mid-term survival after percutaneous MVR OBJECTIVES Corrective surgery for secondary mitral regurgitation ( MR ) by restrictive annuloplasty has proven beneficial in that it improves New York Heart Association ( NYHA ) functional class and induces reverse left ventricular remodelling . However , proof of a survival benefit for these patients is still pending . Percutaneous techniques of mitral valve repair ( MVR ) have become a viable treatment alternative for selected high-risk patients with severe secondary MR . METHODS We retrospectively analysed our prospect i ve hospital data base of patients with severe secondary MR undergoing either surgical MVR or percutaneous treatment using the MitraClip device .  Patient characteristics and 6-month clinical and effectiveness outcomes are reported . RESULTS From March 2002 through June 2010 , 76 patients with secondary MR underwent isolated surgical MVR , while 95 were treated using the MitraClip device at our centre . Patients undergoing MitraClip treatment were significantly older ( mean 72.8 ± 8.2 vs 64.5 ± 11.4 years , P < 0.001 ) , had a lower left ventricular ejection fraction ( mean 36.2 ± 12.5 vs 42.1 ± 16.2 % , P = 0.014 ) and were generally more high risk , with a significantly higher mean logistic EuroSCORE  I compared with surgical c and i date s ( 33.7 ± 18.7 vs 10.1 ± 8.7 % , P < 0.001 ) . Procedural success was 98.7 ( 75 of 76 ) for MVR and 95.8 % ( 91 of 95 ) for MitraClip treatment ( P = 0.383 ) . Thirty-day mortality was 4.2 ( 4 of 95 ) and 2.6 % ( 2 of 76 ; P = 0.557 ) , and the mean grade of residual MR was 1.4 ± 0.8 and 0.2 ± 0.4 ( P < 0.001 ) after MitraClip treatment and surgical MVR , respectively . Six-month survival rates after adjustment for baseline differences were not significantly different in the respective groups ( P = 0.642 ) . CONCLUSIONS In our experience , characteristics and risk factors of patients with severe secondary MR undergoing surgery differ significantly from those considered for percutaneous therapy . Surgery was more effective compared with MitraClip in reducing MR . However , a large proportion of patients benefits from percutaneous intervention with sustained MR Grade < 2 + and improvement in NYHA functional class at 6 months . MitraClip therapy seems to be an adequate alternative to surgery , especially for elderly patients with reduced left ventricular function and relevant comorbidities . Assessment , treatment and postprocedural care of patients by an interdisciplinary team are of paramount importance for clinical success OBJECTIVES The main objective of this study was to assess if the benefits of biventricular ( BiV ) pacing observed during the crossover phase were sustained over 12 months . BACKGROUND MUltisite STimulation In Cardiomyopathies ( MUSTIC ) is a r and omized controlled study intended to evaluate the effects of BiV pacing in patients with New York Heart Association ( NYHA ) class III heart failure and intraventricular conduction delay . METHODS Of 131 patients included , 42/67 in sinus rhythm ( SR ) and 33/64 in atrial fibrillation ( AF ) were followed up longitudinally at 9 and 12 months by 6-min walked distance , peak oxygen uptake ( peak VO(2 ) ) , quality of life by the Minnesota score , NYHA class , echocardiography , and left ventricular ejection fraction by radionuclide technique . RESULTS At 12 months , all SR and 88 % of AF patients were programmed to BiV pacing . Compared with baseline , the 6-min walked distance increased by 20 % ( SR ) ( p = 0.0001 ) and 17 % ( AF ) ( p = 0.004 ) ; the peak VO(2 ) by 11 % ( SR ) and 9 % ( AF ) ; quality of life improved by 36 % ( SR ) ( p = 0.0001 ) and 32 % ( AF ) ( p = 0.002 ) ; NYHA class improved by 25 % ( SR ) ( p = 0.0001 ) and 27 % ( AF ) ( p = 0.0001 ) . The ejection fraction improved by 5 % ( SR ) and 4 % ( AF ) . Mitral regurgitation decreased by 45 % ( SR ) and 50 % ( AF ) . CONCLUSIONS The clinical benefits of BiV pacing appeared to be significantly maintained over a 12-month follow-up period OBJECTIVE The Endovascular Valve Edge-to-Edge Repair Study ( EVEREST II ) is a prospect i ve , multicenter , r and omized controlled trial comparing percutaneous repair with the MitraClip device to mitral valve ( MV ) surgery in the treatment of mitral regurgitation . The present study analyzed the patient characteristics and treatment effects on mitral repair versus replacement . METHODS Of 279 patients enrolled , 80 surgical patients underwent 82 MV operations and 178 underwent an initial MitraClip procedure  , of whom 37 underwent a subsequent MV operation  within 1 year of their index the  MitraClip procedure . A logistic regression model was used to predict MV replacement according to valve pathology , etiology of mitral regurgitation , age , previous cardiac surgery , and treatment group . RESULTS The rate of percutaneous or surgical MV repair at 1 year was 89 % ( 158/178 ) in patients initially receiving the MitraClip device versus 84 % ( 67/80 ) in the surgical patients ( P = .36 ) . Surgical repair was performed after the MitraClip procedure in 20 ( 54 % ) of 37 patients ( P < .001 vs surgery ) . In both the MitraClip device and surgery groups , MV replacement was significantly associated with anterior leaflet pathology ( P = .035 ) . Logistic regression analysis showed that anterior leaflet pathology predicted MV replacement . In 5 ( 13.5 % ) of 37 patients undergoing surgery after MitraClip therapy , replacement was performed in part because of MV injury associated with the MitraClip procedure . CONCLUSIONS These data suggest that anterior leaflet pathology is strongly associated with MV replacement in patients undergoing either de novo MV surgery or surgery after MitraClip therapy . MitraClip therapy has a repair rate similar to surgery through 1 year but also imparts a risk of replacement of a potentially repairable valve The aims of the echocardiographic sub study of this multicenter trial were to evaluate the use of quantitative assessment of mitral regurgitation ( MR ) severity using serial echocardiography and to assess the efficacy of percutaneous mitral valve repair . Previous surgical repair studies did not use quantitative echocardiographic methods . Results of a percutaneous mitral valve repair clip device in a core echocardiographic laboratory were evaluated . Published parameters for quantifying MR were used in a systematic protocol to qualify patients for study entry and evaluate treatment efficacy at discharge and 6 months after clip repair . Baseline results were presented for 55 patients , and follow-up results , for 49 . Ninety-eight percent of required echocardiographic studies were su bmi tted to the core laboratory , and > 85 % of required measurements were possible . At baseline , mean regurgitant volume was 54.8 + /- 24 ml , regurgitant fraction was 46.9 + /-16.2 % , effective regurgitant orifice area was 0.71 + /- 0.40 cm(2 ) , and vena contracta width was 0.66 + /- 0.20 cm . Based on a severity scale of 1 to 4 , mean color flow grade was 3.4 + /- 0.7 , and mean pulmonary vein flow was 2.8 + /- 1.2 . In patients with a clip at 6 months , all measurements of MR severity were significantly decreased versus baseline , with mean regurgitant volume decreased from 50.3 to 27.5 ml ( change -22.8 ml ; p < 0.0001 ) , regurgitant fraction from 44.6 % to 28.9 % ( change -15.7 % ; p < 0.0001 ) , color flow grade from an average of 3.4 to 1.8 ( change -1.6 ; p < 0.0001 ) , and pulmonary vein flow from 2.8 to 1.8 ( change -1.0 ; p < 0.0018 ) . In conclusion , quantitative assessment of MR is feasible in a multicenter trial , and percutaneous mitral repair with the MitraClip produces a sustained decrease in MR severity to moderate or less for > or = 6 months BACKGROUND In patients with chronic heart failure , the use of carvedilol therapy induces clinical and hemodynamic improvement . However , although the benefits of this beta-blocker have been established in patients with chronic heart failure , the mechanisms underlying them and the changes in left ventricular systolic function , diastolic function , and mitral regurgitation during long-term therapy remain unclear . OBJECTIVE To identify the clinical and functional effects of carvedilol , focusing on diastolic function and mitral regurgitation variations . METHODS Forty-five consecutive patients with chronic heart failure ( ejection fraction 24 % + /- 7 % ) , 17 with dilated ischemic and 28 with nonischemic cardiomyopathy , were treated with carvedilol ( mean dose 44 + /- 30 mg ) and matched for clinical ( New York Heart Association functional class and heart failure duration ) and hemodynamic ( cardiac index and pulmonary wedge pressure ) characteristics to a control group . Clinical and echocardiographic variables were measured in the 2 groups at baseline and after 6 months and the results compared . RESULTS After 6 months of treatment with carvedilol , left ventricular ejection fraction had increased from 24 % + /- 7 % to 29 % + /- 9 % ( P < .0001 ) ; this change was caused by a reduction in end-systolic volume index ( 106 + /- 41 vs 93 + /- 37 mL/m(2 ) ; P < . 0001 ) . Deceleration time of early diastolic filling increased ( 134 + /- 74 vs 196 + /- 63 ms ; P < .0001 ) . Seventeen of the 27 patients with demonstrated improvement of left ventricular diastolic filling moved from having a restrictive filling pattern to having a normal or pseudonormal left ventricular filling pattern . In the control group , no significant changes in deceleration time of early diastolic filling were found ( 139 + /- 74 vs 132 + /- 45 ms ; P = not significant ) . The effective regurgitant orifice area decreased significantly in the carvedilol group but not in the control group . These changes were associated with a significant reduction of the mitral regurgitant stroke volume in the carvedilol group ( 50 + /- 25 vs 16 + /- 13 mL ; P < .0001 ) but not in the control group ( 57 + /- 29 vs 47 + /- 24 mL ; P = not significant ) . These changes of mitral regurgitation were closely associated with significant improvement of forward aortic stroke volume ( r = -.57 , P < .0001 ) . These findings were not observed in patients in the control group . CONCLUSIONS The results of this study show that long-term carvedilol therapy in patients with chronic heart failure was able to prevent or partially reverse progressive left ventricular dilatation . The effects on left ventricular remodeling were 
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There was a significant improvement in haemodynamic profile and functional status after implantation .
CONCLUSIONS MitraClip implantation is an option in managing selected high surgical risk patients with severe MR .
The current evidence suggests that MitraClip can be implanted with reproducible safety and feasibility profile in this subgroup of patients .