human
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective To assess the efficacy of video-assisted minimally invasive surgical vs. catheter ablation for the long-st and ing persistent AF . Methods We performed a retrospective comparative analysis in a series of 166 long-st and ing persistent AF patients treated between 2006 and 2009 with either video-assisted minimally invasive ablation ( 83 patients ) , or catheter ablations ( 83 patients ) . The catheter group was screened using a ‘ pair-matched case-control ’ methodology in order to select appropriate statistical comparison c and i date s out of 169 long-st and ing persistent AF patients which were potentially suitable for surgery , but have been treated with catheter approaches in order to balance major prognostic factors between the two groups . Follow-up for all patients ranged from 1 to 3.6 years . Results No patient died postoperatively . One patient suffered from stroke in the surgical group but recovered before discharge . Freedom from AF was obtained in 59.0 % and 74.7 % during follow-up in the catheter group and the surgical group respectively ( P = 0.047 ) . Patients in the catheter group had a significantly higher rate of recurrent arrhythmia ( P = 0.011 , hazard ratio : 0.555 , 95 % CI : 0.354 to 0.872 ) compared with the surgically treated group . The freedom from antiarrhythmic drugs was 44.6 % in the catheter group and 61.4 % in the surgical group ( P = 0.043 ) . Conclusions The video-assisted minimally invasive ablation was safe and effective , and had an optimistic success rate for patients with long-st and ing persistent AF in our retrospective comparative study . Thus , further r and omized studies addressing this issue seem to be justified Background — Catheter ablation ( CA ) and minimally invasive surgical ablation ( SA ) have become accepted therapy for antiarrhythmic drug – refractory atrial fibrillation . This study describes the first r and omized clinical trial comparing their efficacy and safety during a 12-month follow-up . Methods and Results — One hundred twenty-four patients with antiarrhythmic drug – refractory atrial fibrillation with left atrial dilatation and hypertension ( 42 patients , 33 % ) or failed prior CA ( 82 patients , 67 % ) were r and omized to CA ( 63 patients ) or SA ( 61 patients ) . CA consisted of linear antral pulmonary vein isolation and optional additional lines . SA consisted of bipolar radiofrequency isolation of the bilateral pulmonary vein , ganglionated plexi ablation , and left atrial appendage excision with optional additional lines . Follow-up at 6 and 12 months was performed by ECG and 7-day Holter recording . The primary end point , freedom from left atrial arrhythmia > 30 seconds without antiarrhythmic drugs after 12 months , was 36.5 % for CA and 65.6 % for SA ( P=0.0022 ) . There was no difference in effect for subgroups , which was consistent at both sites . The primary safety end point of significant adverse events during the 12-month follow-up was significantly higher for SA than for CA ( n=21 [ 34.4 % ] versus n=10 [ 15.9 % ] ; P=0.027 ) , driven mainly by procedural complications such as pneumothorax , major bleeding , and the need for pacemaker . In the CA group , 1 patient died at 1 month of subarachnoid hemorrhage . Conclusion — In atrial fibrillation patients with dilated left atrium and hypertension or failed prior atrial fibrillation CA , SA is superior to CA in achieving freedom from left atrial arrhythmias after 12 months of follow-up , although the procedural adverse event rate is significantly higher for SA than for CA . Clinical Trial Registration — URL : http:// clinical trials.gov . Unique identifier : NCT00662701 BACKGROUND In our previous prospect i ve and r and omized study , we have demonstrated that the concomitant surgical ablation using saline-irrigated cooled tip radiofrequency ablation ( SICTRA ) system is more effective than subsequent circumferential pulmonary vein isolation ( CPVI ) combined with substrate modification in treating patients with long-st and ing persistent atrial fibrillation ( LS-AF ) and rheumatic heart disease ( RHD ) undergoing cardiac surgery during middle-term follow-up . Whether this strategy also decreases longer-term arrhythmia recurrence is unknown . This study describes the 4-year efficacy of SICTRA for these patients . Furthermore , we seek to compare the electrophysiological characteristics for recurrent atrial tachyarrhythmia ( ATa ) at the session of catheter ablation between two groups . METHODS Long-term follow-up was performed in 95 patients who underwent the catheter ablation strategy ( n=47 , Group A ) or SICTRA ( n=48 , Group B ) combined with valvular surgery for symptomatic LS-AF patients with RHD . RESULTS After one procedure , Group B had a significantly higher freedom from ATa compared with Group A ( 29/48 vs 15/47 , P=0.005 ) after a mean follow-up of 54 months ( range 48 to 63 months ) . Catheter-based mapping and ablation of recurrent ATa showed larger amounts of macro-reentrant atrial tachycardias ( ATs ) in Group B and higher incidence of pulmonary vein ( PV ) recovery in Group A. After multiple catheter ablations for recurrent ATa , sinus rhythm ( SR ) could be maintained equally between two groups . CONCLUSIONS Single procedure success seems to be higher with SICTRA but repeated catheter ablation potentially results in comparable outcomes in treating patients with LS-AF and RHD during long-term follow-up . More macro-reentrant ATs and more PV recoveries are identified to be responsible for ATa in SICTRA and catheter ablation group , respectively Background —The Cox Maze procedure for treatment of medically refractory atrial fibrillation ( AF ) is limited by its complexity and requirement for cardiopulmonary bypass . Long-term follow-up and success using criteria established by the Heart Rhythm Society/European Heart Rhythm Association/European Cardiac Arrhythmia Society consensus statement have not been reported for surgical AF ablation . We describe the results of using a thorascopic approach and radiofrequency energy to perform bilateral pulmonary vein isolation and left atrial ganglionic plexi ablation for treatment of AF . Methods and Results —Forty-five ( 33 paroxysmal ; 12 persistent ) consecutive patients underwent thorascopic bilateral radiofrequency pulmonary vein isolation , ganglionic plexi ablation , ligament of Marshall ablation , and left atrial appendage exclusion by a single surgeon . Forty-three patients were prospect ively followed without antiarrhythmic drugs for a minimum of 1 year with a 30-day continuous event monitor or pacemaker interrogation at 6 and 12 months . Failure was defined as any atrial tachyarrhythmia of > 30 seconds ’ duration occurring > 90 days after surgery . Mean follow-up was 516±181 days ( 202 to 858 days ) . Twenty-eight ( 65 % ) patients had no atrial tachyarrhythmia > 30 seconds by 1 year , and 15 ( 35 % ) patients had atrial tachyarrhythmia recurrences by 1 year . Eight of 15 patients with recurrent AF had catheter ablation result ing in elimination and /or reduction of AF episodes in 7 of 8 patients . Four of 15 patients had AF elimination or reduction with antiarrhythmic drugs alone . Three patients did not benefit from surgery and received rate control only . There were no deaths ; 1 phrenic nerve injury and 2 pleural effusions were the only major complications . Conclusions —The single procedure success at 1-year follow-up for surgical pulmonary vein isolation and ganglionic plexi ablation is 65 % . Atrial tachyarrhythmia recurrences after surgery are usually responsive to catheter ablation and /or antiarrhythmic drugs Purpose Minimally invasive surgical ablation for atrial fibrillation ( AF ) has shown good results and low complications incidence . Our objective was to evaluate feasibility and efficacy of this technique in our center . Methods The procedure included pulmonary vein isolation , ganglionic plexi ablation , ligament of Marshall resection , and left atrial appendage exclusion through beating heart minimally invasive bilateral thoracotomies . Patients were monitored daily by telemedicine during the first 4 months and then by quarterly 24-h Holter monitoring or by implantable cardiac monitor . Ablation success was defined as freedom from any atrial tachyarrhythmia recurrence lasting more than 30 s and from antiarrhythmic drugs . All patients were followed up for a minimum of 12 months . Results Twenty-two consecutive patients with AF , paroxysmal in 27 % and persistent in 73 % , were treated . Mean age was 63 ± 10 years , 86 % were men . Seventy-three percent of patients had previously undergone to one or more catheter ablations . Median follow-up period was 22 months ( 25 ° –75 ° percentile , 20–27 ) . Patients free from any arrhythmia recurrence for at least 6 consecutive months discontinued antiarrhythmic therapy . Ablation was successful in 73 % of patients at 12 months . Freedom from AF recurrences independently from antiarrhythmic therapy status was 91 % at 12 months . Results were consistent in patients that reached 24 months follow-up . There were no deaths . Complications were : one conversion to sternotomy owing to thoracic adherences , one pacemaker implant , and one postoperative hemothorax requiring surgical revision . Conclusions Our results show that minimally invasive surgical ablation was feasible and gave satisfactory results at long-term term follow-up in patients with AF AIMS Pulmonary vein isolation ( PVI ) can be considered for treatment of symptomatic atrial fibrillation ( AF ) . Nowadays , in addition to transcatheter ablation , thoracoscopic surgical PVI is available . The aim of this study is to compare clinical outcome of surgical with transcatheter PVI as first invasive treatment strategy of AF . METHODS AND RESULTS From June 2009 to November 2011 , 33 patients underwent minimally invasive surgical PVI , and were matched ( 1:2 fashion ) retrospectively according to age , sex , and AF type , with 66 patients who underwent transcatheter PVI .  Success was defined as freedom from atrial arrhythmias on 24 h Holter monitoring without use of anti-arrhythmic drugs ( AADs ) at 1 year . Mean age was 52 ± 10 years , 82 % were male . Paroxysmal AF was present in 76 patients ( 77 % ) , persistent AF in 23 ( 23 % ) patients . None underwent prior ablations , and failed on 1.2 ± 0.6 AADs . At 12 months , complete freedom from atrial arrhythmias without AADs in the surgical PVI group was 88 % compared with 41 % in the transcatheter PVI group ( P < 0.001 ) . Freedom from atrial arrhythmias with AADs was 91 vs. 62 % , in the surgical vs. transcatheter PVI group , respectively ( P = 0.002 ) . Complications occurred in seven ( 21 % ) surgical PVI patients , and three ( 5 % ) transcatheter PVI patients ( P = 0.015 ) . CONCLUSION In present matched study comparing a surgical with transcatheter PVI treatment strategy in symptomatic AF patients failed on AADs , but without prior ablations , a surgical PVI strategy was more effective to prevent recurrence of atrial arrhythmias , than a transcatheter PVI treatment strategy . However , complications were more frequent with surgical PVI BACKGROUND Advances in technology such as epicardial bipolar radiofrequency pulmonary vein isolation , ganglionated plexi identification , and isolation and thoracoscopic left atrial appendage exclusion have enabled less invasive surgical options for management of atrial fibrillation . METHODS We performed a prospect i ve , nonr and omized study of consecutive patients with symptomatic paroxysmal atrial fibrillation undergoing a video-assisted , minimally invasive surgical ablation procedure .  The procedure consisted of bilateral , epicardial pulmonary vein isolation with bipolar radiofrequency , partial autonomic denervation , and selective excision of the left atrial appendage . Minimum follow-up was 1 year with long-term monitoring ( 24-hour continuous , 14-day event or pacemaker interrogation ) . RESULTS Between March 2005 and January 2008 , 52 patients ( 35 male ) , mean age 60.3 years ( range , 42 - 79 years ) underwent the procedure . The left atrial appendage was isolated in 88.0 % ( 44/50 ) . Average hospital stay was 5.2 days ( range 3 - 10 days ) . There were no operative deaths or major adverse cardiac events . On long-term monitoring , freedom from atrial fibrillation/flutter/tachycardia was 86.3 % ( 44/51 ) and 80.8 % ( 42/52 ) at 6 and 12 months , respectively . Antiarrhythmic drugs were stopped in 33 of 37 patients and warfarin in 30 of 37 of 
    Output:
    
agent
Subgroup analysis demonstrated similar trends , with higher freedom from AF in the surgical ablation group for paroxysmal AF patients .
The incidence of pacemaker implantation was higher , while no difference in stroke or cardiac tamponade was demonstrated for the surgical versus catheter ablation groups .
Current evidence suggests that epicardial ablative strategies are associated with higher freedom from AF , higher pacemaker implantation rates and comparable neurological complications and cardiac tamponade incidence to catheter ablative treatment .
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective To assess the efficacy of video-assisted minimally invasive surgical vs. catheter ablation for the long-st and ing persistent AF . Methods We performed a retrospective comparative analysis in a series of 166 long-st and ing persistent AF patients treated between 2006 and 2009 with either video-assisted minimally invasive ablation ( 83 patients ) , or catheter ablations ( 83 patients ) . The catheter group was screened using a ‘ pair-matched case-control ’ methodology in order to select appropriate statistical comparison c and i date s out of 169 long-st and ing persistent AF patients which were potentially suitable for surgery , but have been treated with catheter approaches in order to balance major prognostic factors between the two groups . Follow-up for all patients ranged from 1 to 3.6 years . Results No patient died postoperatively . One patient suffered from stroke in the surgical group but recovered before discharge . Freedom from AF was obtained in 59.0 % and 74.7 % during follow-up in the catheter group and the surgical group respectively ( P = 0.047 ) . Patients in the catheter group had a significantly higher rate of recurrent arrhythmia ( P = 0.011 , hazard ratio : 0.555 , 95 % CI : 0.354 to 0.872 ) compared with the surgically treated group . The freedom from antiarrhythmic drugs was 44.6 % in the catheter group and 61.4 % in the surgical group ( P = 0.043 ) . Conclusions The video-assisted minimally invasive ablation was safe and effective , and had an optimistic success rate for patients with long-st and ing persistent AF in our retrospective comparative study . Thus , further r and omized studies addressing this issue seem to be justified Background — Catheter ablation ( CA ) and minimally invasive surgical ablation ( SA ) have become accepted therapy for antiarrhythmic drug – refractory atrial fibrillation . This study describes the first r and omized clinical trial comparing their efficacy and safety during a 12-month follow-up . Methods and Results — One hundred twenty-four patients with antiarrhythmic drug – refractory atrial fibrillation with left atrial dilatation and hypertension ( 42 patients , 33 % ) or failed prior CA ( 82 patients , 67 % ) were r and omized to CA ( 63 patients ) or SA ( 61 patients ) . CA consisted of linear antral pulmonary vein isolation and optional additional lines . SA consisted of bipolar radiofrequency isolation of the bilateral pulmonary vein , ganglionated plexi ablation , and left atrial appendage excision with optional additional lines . Follow-up at 6 and 12 months was performed by ECG and 7-day Holter recording . The primary end point , freedom from left atrial arrhythmia > 30 seconds without antiarrhythmic drugs after 12 months , was 36.5 % for CA and 65.6 % for SA ( P=0.0022 ) . There was no difference in effect for subgroups , which was consistent at both sites . The primary safety end point of significant adverse events during the 12-month follow-up was significantly higher for SA than for CA ( n=21 [ 34.4 % ] versus n=10 [ 15.9 % ] ; P=0.027 ) , driven mainly by procedural complications such as pneumothorax , major bleeding , and the need for pacemaker . In the CA group , 1 patient died at 1 month of subarachnoid hemorrhage . Conclusion — In atrial fibrillation patients with dilated left atrium and hypertension or failed prior atrial fibrillation CA , SA is superior to CA in achieving freedom from left atrial arrhythmias after 12 months of follow-up , although the procedural adverse event rate is significantly higher for SA than for CA . Clinical Trial Registration — URL : http:// clinical trials.gov . Unique identifier : NCT00662701 BACKGROUND In our previous prospect i ve and r and omized study , we have demonstrated that the concomitant surgical ablation using saline-irrigated cooled tip radiofrequency ablation ( SICTRA ) system is more effective than subsequent circumferential pulmonary vein isolation ( CPVI ) combined with substrate modification in treating patients with long-st and ing persistent atrial fibrillation ( LS-AF ) and rheumatic heart disease ( RHD ) undergoing cardiac surgery during middle-term follow-up . Whether this strategy also decreases longer-term arrhythmia recurrence is unknown . This study describes the 4-year efficacy of SICTRA for these patients . Furthermore , we seek to compare the electrophysiological characteristics for recurrent atrial tachyarrhythmia ( ATa ) at the session of catheter ablation between two groups . METHODS Long-term follow-up was performed in 95 patients who underwent the catheter ablation strategy ( n=47 , Group A ) or SICTRA ( n=48 , Group B ) combined with valvular surgery for symptomatic LS-AF patients with RHD . RESULTS After one procedure , Group B had a significantly higher freedom from ATa compared with Group A ( 29/48 vs 15/47 , P=0.005 ) after a mean follow-up of 54 months ( range 48 to 63 months ) . Catheter-based mapping and ablation of recurrent ATa showed larger amounts of macro-reentrant atrial tachycardias ( ATs ) in Group B and higher incidence of pulmonary vein ( PV ) recovery in Group A. After multiple catheter ablations for recurrent ATa , sinus rhythm ( SR ) could be maintained equally between two groups . CONCLUSIONS Single procedure success seems to be higher with SICTRA but repeated catheter ablation potentially results in comparable outcomes in treating patients with LS-AF and RHD during long-term follow-up . More macro-reentrant ATs and more PV recoveries are identified to be responsible for ATa in SICTRA and catheter ablation group , respectively Background —The Cox Maze procedure for treatment of medically refractory atrial fibrillation ( AF ) is limited by its complexity and requirement for cardiopulmonary bypass . Long-term follow-up and success using criteria established by the Heart Rhythm Society/European Heart Rhythm Association/European Cardiac Arrhythmia Society consensus statement have not been reported for surgical AF ablation . We describe the results of using a thorascopic approach and radiofrequency energy to perform bilateral pulmonary vein isolation and left atrial ganglionic plexi ablation for treatment of AF . Methods and Results —Forty-five ( 33 paroxysmal ; 12 persistent ) consecutive patients underwent thorascopic bilateral radiofrequency pulmonary vein isolation , ganglionic plexi ablation , ligament of Marshall ablation , and left atrial appendage exclusion by a single surgeon . Forty-three patients were prospect ively followed without antiarrhythmic drugs for a minimum of 1 year with a 30-day continuous event monitor or pacemaker interrogation at 6 and 12 months . Failure was defined as any atrial tachyarrhythmia of > 30 seconds ’ duration occurring > 90 days after surgery . Mean follow-up was 516±181 days ( 202 to 858 days ) . Twenty-eight ( 65 % ) patients had no atrial tachyarrhythmia > 30 seconds by 1 year , and 15 ( 35 % ) patients had atrial tachyarrhythmia recurrences by 1 year . Eight of 15 patients with recurrent AF had catheter ablation result ing in elimination and /or reduction of AF episodes in 7 of 8 patients . Four of 15 patients had AF elimination or reduction with antiarrhythmic drugs alone . Three patients did not benefit from surgery and received rate control only . There were no deaths ; 1 phrenic nerve injury and 2 pleural effusions were the only major complications . Conclusions —The single procedure success at 1-year follow-up for surgical pulmonary vein isolation and ganglionic plexi ablation is 65 % . Atrial tachyarrhythmia recurrences after surgery are usually responsive to catheter ablation and /or antiarrhythmic drugs Purpose Minimally invasive surgical ablation for atrial fibrillation ( AF ) has shown good results and low complications incidence . Our objective was to evaluate feasibility and efficacy of this technique in our center . Methods The procedure included pulmonary vein isolation , ganglionic plexi ablation , ligament of Marshall resection , and left atrial appendage exclusion through beating heart minimally invasive bilateral thoracotomies . Patients were monitored daily by telemedicine during the first 4 months and then by quarterly 24-h Holter monitoring or by implantable cardiac monitor . Ablation success was defined as freedom from any atrial tachyarrhythmia recurrence lasting more than 30 s and from antiarrhythmic drugs . All patients were followed up for a minimum of 12 months . Results Twenty-two consecutive patients with AF , paroxysmal in 27 % and persistent in 73 % , were treated . Mean age was 63 ± 10 years , 86 % were men . Seventy-three percent of patients had previously undergone to one or more catheter ablations . Median follow-up period was 22 months ( 25 ° –75 ° percentile , 20–27 ) . Patients free from any arrhythmia recurrence for at least 6 consecutive months discontinued antiarrhythmic therapy . Ablation was successful in 73 % of patients at 12 months . Freedom from AF recurrences independently from antiarrhythmic therapy status was 91 % at 12 months . Results were consistent in patients that reached 24 months follow-up . There were no deaths . Complications were : one conversion to sternotomy owing to thoracic adherences , one pacemaker implant , and one postoperative hemothorax requiring surgical revision . Conclusions Our results show that minimally invasive surgical ablation was feasible and gave satisfactory results at long-term term follow-up in patients with AF AIMS Pulmonary vein isolation ( PVI ) can be considered for treatment of symptomatic atrial fibrillation ( AF ) . Nowadays , in addition to transcatheter ablation , thoracoscopic surgical PVI is available . The aim of this study is to compare clinical outcome of surgical with transcatheter PVI as first invasive treatment strategy of AF . METHODS AND RESULTS From June 2009 to November 2011 , 33 patients underwent minimally invasive surgical PVI , and were matched ( 1:2 fashion ) retrospectively according to age , sex , and AF type , with 66 patients who underwent transcatheter PVI .  Success was defined as freedom from atrial arrhythmias on 24 h Holter monitoring without use of anti-arrhythmic drugs ( AADs ) at 1 year . Mean age was 52 ± 10 years , 82 % were male . Paroxysmal AF was present in 76 patients ( 77 % ) , persistent AF in 23 ( 23 % ) patients . None underwent prior ablations , and failed on 1.2 ± 0.6 AADs . At 12 months , complete freedom from atrial arrhythmias without AADs in the surgical PVI group was 88 % compared with 41 % in the transcatheter PVI group ( P < 0.001 ) . Freedom from atrial arrhythmias with AADs was 91 vs. 62 % , in the surgical vs. transcatheter PVI group , respectively ( P = 0.002 ) . Complications occurred in seven ( 21 % ) surgical PVI patients , and three ( 5 % ) transcatheter PVI patients ( P = 0.015 ) . CONCLUSION In present matched study comparing a surgical with transcatheter PVI treatment strategy in symptomatic AF patients failed on AADs , but without prior ablations , a surgical PVI strategy was more effective to prevent recurrence of atrial arrhythmias , than a transcatheter PVI treatment strategy . However , complications were more frequent with surgical PVI BACKGROUND Advances in technology such as epicardial bipolar radiofrequency pulmonary vein isolation , ganglionated plexi identification , and isolation and thoracoscopic left atrial appendage exclusion have enabled less invasive surgical options for management of atrial fibrillation . METHODS We performed a prospect i ve , nonr and omized study of consecutive patients with symptomatic paroxysmal atrial fibrillation undergoing a video-assisted , minimally invasive surgical ablation procedure .  The procedure consisted of bilateral , epicardial pulmonary vein isolation with bipolar radiofrequency , partial autonomic denervation , and selective excision of the left atrial appendage . Minimum follow-up was 1 year with long-term monitoring ( 24-hour continuous , 14-day event or pacemaker interrogation ) . RESULTS Between March 2005 and January 2008 , 52 patients ( 35 male ) , mean age 60.3 years ( range , 42 - 79 years ) underwent the procedure . The left atrial appendage was isolated in 88.0 % ( 44/50 ) . Average hospital stay was 5.2 days ( range 3 - 10 days ) . There were no operative deaths or major adverse cardiac events . On long-term monitoring , freedom from atrial fibrillation/flutter/tachycardia was 86.3 % ( 44/51 ) and 80.8 % ( 42/52 ) at 6 and 12 months , respectively . Antiarrhythmic drugs were stopped in 33 of 37 patients and warfarin in 30 of 37 of 
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