***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: Abstract . The present study was conducted to evaluate the degree of stress in patients induced by minimally invasive cardiac surgery ( MICS )  in comparison with that caused by conventional cardiac surgery . We did this by assessing the incidence of systemic inflammatory response syndrome ( SIRS ) .  A total of 48 adult patients who underwent surgery for single valve disease were included in this study , 27 of whom underwent conventional surgery and 21 MICS .  We evaluated the stress inflicted on the patients in these two groups by analyzing the duration and degree of SIRS and the level of C-reactive protein ( CRP ) . SIRS was assessed by measuring body temperature , heart rate , respiratory rate , and white blood cell counts . There were no significant differences in the operating times , perfusion times , or aorta clamp times between the two groups ; and the mean volume of blood transfusion did not differ significantly either . There was no significant difference in the incidence of SIRS or the mean duration of SIRS between the two groups . The CRP levels did not differ significantly between the two groups . Thus although MICS is superior to conventional cardiac surgery in that only a small skin incision is required , the stress experienced by the patient may be the same as that experienced by the patient undergoing conventional cardiac surgery Introduction —Although minimally invasive aortic valve surgery ( MIAVR ) is performed in many centers , few studies have compared its results to a st and ard sternotomy ( SS ) approach . We assessed the hypothesis that , when compared with SS in the elderly population , MIAVR has similar morbidity and mortality and allows faster hospital recovery . Methods and Results —From January 1995 through February 2002 , 515 patients over age 65 underwent isolated aortic valve replacement .  Using data gathered prospect ively , 189 MIAVR patients were matched with 189 SS patients by age , ventricular function , valvular pathology , urgency of operation , diabetes , previous cardiac surgery , renal disease , and history of stroke . In each group , 56.1 % of patients underwent non-elective procedures , and 28 % were ≥80 years old . Hospital mortality ( 6.9 % ) and freedom from postoperative morbidity ( 82.5 % versus 81.5 % , P = 0.79 ) were similar . Multivariate analysis revealed that urgent procedures [ Odds Ratio (OR)=3.97 ; P = 0.03 ] , congestive heart failure ( OR=3.94 ; P = 0.03 ) , and ejection fraction < 30 % ( OR=4.16 ; P = 0.03 ) were significant predictors of hospital mortality . Prolonged length of stay was associated with age ( P = 0.05 ) , preoperative stroke ( OR=3.5 , P = 0.001 ) , CHF ( OR=2.2 , P = 0.004 ) , and sternotomy approach ( OR=2.3 , P = 0.002 ) by multivariate analysis . More MIAVR patients were discharged home ( 52.6 % versus 38.6 % , P = 0.03 ) rather than to rehabilitation facilities . Three year actuarial survival revealed no difference between groups . Conclusions —Minimally invasive aortic valve surgery is safe in elderly patients , with morbidity and mortality comparable to sternotomy approach . The shorter hospital stay and greater percentage of patients discharged home after MIAVR reflect enhanced recovery with this technique OBJECTIVES Aortic valve replacement ( AVR ) via minimally invasive surgery ( MIS ) may provide clinical benefits in patients with aortic valve disease . A new class of bioprosthetic valves that enable rapid deployment AVR ( RDAVR ) may facilitate MIS . We here report the 1-year results of a r and omized , multicentre trial comparing the outcomes for MIS-RDAVR with those for conventional AVR via full sternotomy ( FS ) with a commercially available stented aortic bioprosthesis . METHODS A total of 100 patients with aortic stenosis were enrolled in a prospect i ve , multicentre , r and omized comparison trial ( CADENCE-MIS ) . Key exclusion criteria included AVR requiring concomitant procedures , ejection fraction of < 25 % and recent myocardial infa rct ion or stroke . Patients were r and omized to undergo MIS-RDAVR via upper hemisternotomy ( EDWARDS INTUITY ) or AVR via FS with a commercially available stented valve . Procedural , early and late clinical outcomes were assessed for both groups . Haemodynamic performance was evaluated by an echocardiography CoreLaboratory . RESULTS Technical success was achieved in 94 % of MIS-RDAVR patients . MIS-RDAVR was associated with significantly reduced cross-clamp times compared with FS ( 41.3 ± 20.3 vs 54.0 ± 20.3 min , P < 0.001 ) . Clinical and functional outcomes were similar at 30 days and 1 year postoperatively for both groups . While both groups received a similarly sized implanted valve ( 22.9 ± 2.1 mm MIS-RDAVR vs 23.0 ± 2.1 mm FS-AVR ; P = 0.91 ) , MIS-RDAVR patients had significantly lower peak gradients 1 year postoperatively ( 16.9 ± 5.3 vs 21.9 ± 8.6 mmHg ; P = 0.033 ) and a trend towards lower mean gradients ( 9.1 ± 2.9 vs 11.5 ± 4.3 mmHg ; P = 0.082 ) . In addition , MIS-RDAVR patients had a significantly larger effective orifice area 1 year postoperatively ( 1.9 ± 0.5 vs 1.7 ± 0.4 cm2 ; P = 0.047 ) . Paravalvular leaks , however , were significantly more common in the MIS-RDAVR group ( P = 0.027 ) . CONCLUSIONS MIS-RDAVR is associated with a significantly reduced cross-clamp time and better valvular haemodynamic function than FS-AVR . However , paravalvular leak rates are higher with MIS-RDAVR OBJECTIVE The purpose of this study was to compare the respiratory function of patients operated either with a ministernotomy or with a conventional sternotomy for an aortic valve replacement . DESIGN A prospect i ve r and omized study . SETTING A single-institution university hospital . PARTICIPANTS Seventy-eight patients scheduled for aortic valve replacement . INTERVENTIONS Patients were assigned to have  minimal sternotomy access ( ministernotomy ) or conventional median total sternotomy .  Pulmonary function was measured using a mobile respiratory spirometric device preoperatively and after 1 ( POD1 ) , 2 ( POD2 ) , and 7 days ( POD7 ) postoperatively . MEASUREMENTS AND MAIN RESULTS There was no significant difference in any respiratory parameter measured between the 2 groups of patients . Almost all respiratory volumes decreased significantly with the same intensity in the 2 groups on POD1 ( p < 0.05 ) , by about 50 % from baseline . Only functional residual capacity was unchanged from baseline in the postoperative period , except for a small but significant reduction of this parameter to 60.3 % + /- 27.4 % in the st and ard sternotomy group on POD1 and 60.9 % + /- 27.1 % and 58.8 % + /- 30.4 % , respectively , in the ministernotomy and the st and ard group at POD7 . The only significant difference concerned the intraoperative blood loss measured at 450 + /- 280 mL and 720 + /- 450 mL , respectively , in the ministernotomy and the st and ard group ( p < 0.05 ) , but this was not significantly associated with a reduction of total blood use . CONCLUSION This study failed to show any improvement of respiratory function by a smaller chest incision . However , it showed a significant reduction in intraoperative bleeding but without a reduction in transfusion . Further investigations are required to assess whether this procedure could improve the outcome of cardiac surgery patients with a greater predicted risk score or pulmonary diseases BACKGROUND Minimally invasive surgical procedures ( MIS ) may offer several advantages over conventional full sternotomy ( FS ) aortic valve replacement ( AVR ) . A novel class of aortic valve prostheses has been developed for rapid-deployment AVR ( RDAVR ) . We report a r and omized , multicenter trial comparing the outcomes for MIS-RDAVR with those of conventional FS-AVR . METHODS A total of 100 patients with aortic stenosis were enrolled in a prospect i ve , multicenter , r and omized comparison trial ( CADENCE-MIS ) . Exclusion criteria included ejection fraction below 25 % , AVR requiring concomitant procedures , and recent myocardial infa rct ion or stroke . Patients were r and omized to undergo MIS-RDAVR through an upper hemisternotomy ( n = 51 ) or AVR by FS with a conventional stented bioprosthesis ( n = 49 ) . Three patients were excluded before the procedure , and 3 more patients who were r and omized to undergo RDAVR were excluded because of their anatomy . Procedural , early clinical outcomes , and functional outcomes were assessed for the remaining 94 patients . Hemodynamic performance was assessed by an echocardiography core laboratory . RESULTS Implanted valve sizes were similar between groups ( 22.9 ± 2.1 vs 23.0 ± 2.1 mm , p = 0.9 ) . MIS-RDAVR was associated with significantly reduced aortic cross-clamp times compared with FS-AVR ( 41.3 ± 20.3 vs 54.0 ± 20.3 minutes , p < 0.001 ) , although cardiopulmonary bypass times were similar ( 68.8 ± 29.0 vs 74.4 ± 28.4 minutes , p = 0.21 ) . Early clinical outcomes were similar between the two groups , including quality of life measures . The RDAVR patients had a significantly lower mean transvalvular gradient ( 8.5 vs 10.3 mm Hg , p = 0.044 ) and a lower prevalence of patient-prosthesis mismatch ( 0 % vs 15.0 % , p = 0.013 ) 3 months postoperatively compared with the FS-AVR patients . CONCLUSIONS RDAVR by the MIS approach is associated with significantly reduced myocardial ischemic time and better valvular hemodynamic function than FS-AVR with a conventional stented bioprosthesis . Rapid deployment valves may facilitate the performance of MIS-AVR Background During the last decade , the use of ministernotomy in cardiac surgery has increased . Quality of life and patient satisfaction after ministernotomy have never been compared to conventional full sternotomy in r and omised trials . The aim of the study is to determine if this minimally invasive approach improves quality of life , satisfaction and clinical morbimortality outcomes . Methods / design The QUALITY -AVR trial is a single-blind , single-centre , independent , and pragmatic r and omised clinical trial comparing ministernotomy ( “ J ” shaped upper hemisternotomy toward right 4th intercostal space ) to full sternotomy in patients with isolated severe aortic stenosis scheduled for elective aortic valve replacement . One hundred patients will be r and omised in a 1:1 computational fashion . Sample size was determined for the primary end point with alpha error of 0.05 and with power of 90 % in detecting differences between intervention groups of ≥ 0.10 points in change from baseline quality of life Question naire EuroQOL-index ( EQ-5D-5 L ® ) , measured at 1 , 6 or 12 months . Secondary endpoints are : the differences in change from other baseline EQ-5D-5 L ® utilities ( visual analogue scale , Health Index and Severity Index ) , cardiac surgery specific satisfaction question naire ( SATISCORE ® ) , a combined safety endpoint of four major adverse complications at 1 month ( all-cause mortality , acute myocardial infa rct ion , neurologic events and acute renal failure ) , bleeding through drains within the first 24 h , intubation time , postoperative hospital and intensive care unit length of stay , transfusion needs during the first 72 h and 1-year survival rates . Clinical follow up is scheduled at baseline , 1 , 6 , and 12 months after r and omization . All clinical outcomes are recorded following the Valve Academic Research Consortium 2 criteria . Discussion The QUALITY -AVR trial aims to test the hypothesis that ministernotomy  improves quality of life , satisfaction and clinical outcomes in patients referred for isolated aortic valve replacement . Statistically significant differences favouring ministernotomy could modify the surgical “ gold st and ard ” for aortic stenosis surgery , and subsequently the need to change the control group in transcatheter aortic valve implantation trials . Recruitment started on 18 March 2016 . In November 2017 , 75 patients were enrolled . Trial registration Clinical Trials.gov , NCT02726087 . Registered on 13 March 2016 BACKGROUND Minimally invasive surgical approaches have been applied recently in the management of valvular heart disease . In this report , we review ed our preliminary experience of minimally invasive aortic valve replacement . METHODS Eighteen patients were operated on by 
    Output:
    
Clinical heterogeneity both between and within studies is a relatively fixed feature of surgical trials , and this also contributed to the need for caution in interpreting results .Considering these limitations , there was uncertainty of the effect on mortality or extracorporeal support times with upper hemi-sternotomy for aortic valve replacement compared to full median sternotomy .
There was also uncertainty of any difference in the rates of other , secondary outcome measures or adverse events with minimally invasive limited sternotomy approaches to aortic valve replacement .
There appears to be uncertainty between minimally invasive aortic valve replacement via upper hemi-sternotomy and conventional aortic valve replacement via a full median sternotomy .