Clinical Application Of Radiofrequency Ablation Treating Atrial Fibrilation During Heart Valve Replacement

Objective: To evaluate the efficacy of surgical treatment for atrial fibrillation by bipolarradiofrequency ablation during heart valve replacement and explore the clinical applicationof surgical treatment of atrial fibrillation combined with heart valve disease.Methods: Data was collected as a part of valve surgery in Cardiovascular Surgery of theGeneral Hospital of Shenyang Military Region through July2006to May2010．GroupA enrolled257patients of valvular heart diseases with atrial fibrillationunderwent bipolar radiofrequency ablation during valve replacement.Group B enrolled103patients of valvular heart disease with atrial fibrillation underwent valve replace-ment alone over the same period. The duration of cardiopulmonary bypass, the timeof clamping aorta, the duration of postoperative mechanical ventilator assisted, thetotal drainage after surgery the first3postoperative days,the staying duration in ICU,the duration of postoperative hospitalization, the perioperative deaths and the hospital-lizetion death both two groups were recorded for statistical analysis. For patientsfollowed up for one year both two groups, the elimination rates of atrial fibrillationwere compared at discharge, three months, six months and one year after operation,respectively. Left atrial diameter, left ventricular diameter, left ventricular ejectionfraction and cardiothoracic ratio were also compared1-year after surgery betweentwo groups and compared with the corresponding preoperative indexes as well.Results:1. Preliminary Results: All procedures were successfully completed. There were nointra-operative deaths both two groups. In group A, the cardiopulmonary bypass (CPB)duration was104.2±14.7minutes; the aortic clamping duration was71.3±11.9minutes;the postoperative mechanical ventilator-assisted duration was13.2±8.8hours; the stayingin intensive care unit (ICU) was4.91±2.04days; The total drainage of the first3postoperative days was552.9±181.4ml; the postoperative hospitalized staying was17.62 ±10.04days; there were241patients under sinus or nodal rhythm at the end of surgery. Ingroup B, the cardiopulmonary bypass duration was76.3±19.3minutes; the aorticcross-clamp duration was53.6±14.2minutes; the postoperative mechanicalventilator-assisted duration was12.7±9.1hours; the length of stay in ICU was4.64±2.26days; The total drainage of the first3postoperative days was426.3±178.7ml; thepostoperative hospitalized staying was18.18±9.87days; there were17patients undersinus or nodal rhythm at the end of surgery. Death during hospitalization: There were fourdeaths in group A including three patients died of heart failure and another died of renalfailure. There were two deaths in group B including one patient died of heart failure andanother died of sudden cardiac arrhythmia. The mechanical ventilator-assisted duration, thelength of staying in ICU, postoperative hospitalized stay and the death duringhospitalization were contrasted between two groups to show no significant difference, whilethe cardiopulmonary bypass duration, aortic cross-clamp duration and drainage volumewere significantly different between two groups3-day after surgery.2. Postoperative follow-up results of elimination rate of atrial fibrillation at differenttimes:186patients in group A (follow-up rate of72.4%) were statistically given aboutelimination rates of atrial fibrillation at discharged, postoperative3-month,6-month and1-year, and the sinus rhythm appeared in164cases (88.1%) at discharge,161cases (86.6%)at three months,159cases (85.5%) at six months and171cases (91.9%) at one year. Thestatistical results of73patients in group B (follow-up rate of70.9%) showed that the sinusrhythm was appeared in12cases (16.4%) at discharge,11cases (15.1%) at three months,10cases (13.7%) at six months and13cases (17.8%) at one year. The elimination rates ofatrial fibrillation at of four points in time in group A were all higher than group B, and thedifference was statistically significant, P<0.05.3. Postoperative1-year follow-up results in two groups:186patients in group A(follow-up rate of72.4%) the cardiothoracic ratio were52.6±8.5mm, left atrial diameterranged43.2±6.7mm, left ventricular diameter ranged44.6±7.1mm and left ventricularejection fraction (%) were60.3±8.7;73patients in group B (follow-up rate of70.9%)the cardiothoracic ratio were58.4±9.7mm, left atrial diameter ranged48.9±5.4mm, leftventricular diameter ranged49.2±4.6mm and left ventricular ejection fraction (%) were60.0±9.1. The postoperative1-year indexes were compared to those before surgery in twogroups, and the results of cardiothoracic ratio, left atrial internal diameter and left ventricular transverse diameter showed a significant differences, P<0.05; but there was nosignificant difference in the left ventricular ejection fraction. The indexes of1-year followedup were compared with that at admitted each other respectively between two groups,cardiothoracic ratio, left atrial diameter and left ventricular diameter showed significantlydifferences, P<0.05; there was no significant difference in the left ventricular ejectionfraction.Conclusion:Bipolar radiofrequency ablation used in open heart surgery for patients with valvularheart disease and atrial fibrillation is a safe, feasible and effective method of treatment. Itcan eliminate the harm of postoperative atrial fibrillation to patient, effectively reduce theeconomic burden of drugs and interventional therapy due to atrial fibrillation. The methodof treatment have a satisfactory postoperative recovery of cardiac function and betterclinical efficacy.