On-pump mini-invasive mitral valve surgery via right submammary thoracotomy: A clinical analysis / 第二军医大学学报

ABSTRACT

Objective to summarize the clinical experience and results of 50 cases of mitral valve surgery via right anterolateral mini-thoracotomy technique. Methods Patients of mitral valve diseases who accepted such less invasive technique with cap lamp between October 2008 and February 2010 were reviewed.Out of a total 50 cases,38 rheumatic cases underwent mitral valve replacement,12 degenerative cases underwent mitral valvuloplasty,22 cases underwent associated tricuspid valvuloplasty.Preoperative transthoracic echocardiography(TTE) manifest mean left ventricular ejection fraction(LVEF) was 57.3±6.0%.According to NYHA classification,32 patients were in NYHA class II while the other 18 in class III. Diagnosis was identified according to history, physical examination, ECG as well as TTE. There was no statistical difference with regard to age, body weight, cradiothoracic ratio,size of left atrium,size of left ventricle and LVEF comparing with homochronous mitral valve surgeries via median sternotomy.All the patients adopted single lumen trachea cannula and were positioned on his/her back with a 20-30 elevation of the right side, the right arm was suspended over the head. Cardiopulmonary bypass was established between the femoral artery and bicaval venous cannulation. A 6-8cm incision was created in the right submammary fold and the right chest cavity was entered through the fourth intercostalspace.In addition,two other ports were necessary with one positioned at the cross-point of right medioclavicular line and second intercostalspace for placing long myocardial perfusion needles and superior vena cava blocking belt and the other positioned at the cross-point of right midaxillary line and fourth intercostalspace for placing special aortic clamp as well as inferior vena cava blocking belt. Surgeons should wearing headlamps to obtain a clear operation field. The procedures were then performed through an interatrial septum or interatrial groove incision.Result None of the 50 patients turned into median sternotomy during surgeries, there was no case of prolonged intubation, failure of important organs, hemoglobinuria or death,4 cases appeared hypoxemia during surgeries because of high-frequency ventilation with low tidal volume and all Improved after being treated. One case was complicated by active bleeding of intercostal arteries and recovered uneventfully after secondary hemostasis. Comparing with a group made up of 50 patients of the same period who underwent traditional mitral valve surgery through median sternotomy, there was no statistical difference regarding total operation time(130-206,152.0±42.6min120-190,145.6±50.4min),the mean bypass time(58-147,75.1±20.3min56-140,72.0±19.3min),the cross-clamp time (29-71,42.9±16.5min 27-66,41.7±14.7min),mean parallel cycle time(18-60,28.5±12.8min21-50,29.5±12.0min)(P>0.05). Tracheal intubation time was similar for both groups.(3.5-12,5.2±2.8h4-14,5.5±2.6h)(P>0.05).The drainage volume of the mini-invasive group was significantly less when comparing with traditional group and all removed their chest tubes on 1st postoperative day.The mean volume were 40-600(105±40)ml and 150-1000 (300±80) ml, respectively(P<0.05). Volume of blood transfusion was also significantly less than traditional group(200±50ml300±100ml)(P<0.05).TTE before discharged manifest all mitral valve prosthesis had good function, no paravalvular leak was detected, mitral regurgitation and tricuspid regurgitation following valvuloplasty was mild.Conclusion On-pump mini-invasive mitral valve surgery via right submammary thoracotomy which entered the right chest cavity through the fourth intercostalspace together with the using of headlamps can provide a clear operation field. The operating procedure is simple, more important, it is less invasive, less draining and has shorter mean hospital stay and hidden incision. The operation is safety and early postoperative result of this new procedure is satisfactory.