A Clinical Study Of The Minimally Invasive Mitral Valve Surgery

Background. Minimally invasive cardiac surgery has dramatically developed for the past 10 years.Institutional experiences with good outcomes have been reported. This study compares our less invasive technique through a right anterior mini-thoracotomy with conventional sternotomy mitral valve surgery. We summarize our experience at the same time.Methods. Between October 2009 and May 2010,50 patients,who were under 70 years old,needed to undertake a mitral valve surgery for rheumatic heart disease or mitral regurgitation,NYHA classⅡ-Ⅳand no history of cadiothoracic surgery, were selected in this study.Patient with aortic valve disease or coronary artery disease was excluded.They were divided into Group A(24 patients) for minimally invasive mitral valve surgery or Group B(26 patients) for sternotomy surgrey.Preoperative and postoperative echocardiography were performed.Plasma concentration of NT-proBNP was measured.Cross clamp time, cardiopulmarary bypass time,drainage,blood transfusion,condition of patient in ICU and pain intensity were recorded.Results. There was no hospital mortality in either group.Low cardiac output syndrome,respiratory complications and central nervous systom complications were not observed.There was no reoperation for bleeding and no intraoperative conversion to sternotomy in Group A.10 patients(41.7%) in Group A had no blood tranfusion at all versus 3 patient(11.5%) in Group B. There were no statistical differences in age,weight,NYHA,preoperative LVEF,LV,LA, time to establish CPB, cross clamp time,CPB time, lengh of ICU stay and packed red blood cells transfusion.Operation time in Group A was shorter than in Group B(139.7±35.3min vs 186.6±46.5min p=0.04).Less drainage was observed in Group A (230±110ml vs 460±154ml ml p=0.02).Time of ventilation and postoperative hospital stay were shorter【8.6±2.7h vs 14.1±6.5h p=0.006; 7(7-8)d vs 9(8-10)d p=0.002】. No paravalvular leakage in patients undertaken mitral valve replacement and no/less regurgitation in patients undertaken mitral valve plasty were observed by Echocardiography at the 4th day after operation. Plasma concentration of NT-proBNP was highest at the 3rd day postoperatively.NT-proBNP of 7 days postoperatively was on a declining curve,compared with that of 3 days postoperatively.There were 22 patients(91.7%) in Group A on a decrease of more than 30% and 21 patients in Group B(80.8%),whose differences were not statistically significant. The mean length of incision was obviously shorter in Group than that in Group B(5.9±0.6cm vs 22.4±2.5cm p<0.001).All patients had no wound infection and were satisfied with the minimally invasive cardiac surgery(MICS).Most of the patients assumed MICS a better alternative for its good cosmetic outcome,based on the same healing effect of the conventional surgery.Conclusions. The right anterior mini-thoracotomy technique is safe and reliable, with less trauma, less post-operative blood transfusion, good cosmetic results and similarly clinical results compared with sternotomy surgery.