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: Background —Atrioventricular nodal radiofrequency ablation ( AVNA ) with permanent ventricular pacing can be used to control rate in patients with atrial fibrillation ( AF ) . However , long-term outcomes after AVNA are uncertain , especially in light of irreversible pacemaker dependence . Methods and Results —We examined 9122 consecutive patients with AF . The outcomes in 453 patients with AVNA ( 26 % of whom underwent an implantable cardiac defibrillator implant and 37 % underwent cardiac resynchronization therapy implant ) were compared with AF patients without AVNA after propensity score 1:1 matching . During follow-up in the propensity-matched cohort ( 2.41±3.23 years , median 1.23 , quartiles 0.33–3.12 ) , 100 patients died ( yearly rate of death 6.6 % ) . Mode of death was available in 86 % of patients , which was cardiovascular in 67 % of the patients ( related to heart failure in 38 % , sudden death in 5 % , and other cardiovascular reason in 24 % ) and noncardiovascular in 33 % . AVNA in patients with AF was associated with a lower risk of mortality ( odds ratio 0.47 , 95 % confidence interval , 0.29–0.77 ; P=0.003 ) , a lower risk of cardiovascular mortality ( odds ratio = 0.41 , 95 % confidence interval 0.23–0.73 ; P=0.003 ) , and nonsignificant lower risk of stroke and thromboembolic events ( odds ratio = 0.61 , 95 % confidence interval 0.36–1.06 ; P=0.08 ) . Conclusions —In sick AF patients with multiple comorbidities  , AVNA with permanent ventricular pacing for rate control seems safe during follow-up and may be associated with lower mortality Background A prolonged PR interval is known to be a poor prognostic factor in cardiovascular disease . The aim of this study was to investigate the association between PR interval and clinical outcome in patients undergoing radiofrequency catheter ablation ( RFCA ) of atrial fibrillation ( AF ) . Methods and Results We prospect ively included 576 patients with AF ( 75.5 % male , 57.8±11.6 years old , 68.8 % paroxysmal AF ) who underwent RFCA .  We analyzed preprocedural sinus rhythm ECGs obtained in the absence of antiarrhythmic drug , and all enrolled patients were categorized into 4 groups based on the quartile values of the PR interval ( 166 , 182 , and 202 ms ) , and were analyzed according to the left atrium ( LA ) volume ( CT ; Computed tomography ) , LA voltage ( NavX ) , and clinical outcome of AF ablation . Based on quartile value of PR interval , the highest quartile of PR interval ( Q4 ; PR ≥202 ms ) was oldest ( P<0.001 ) , and most likely to have persistent AF ( P<0.001 ) and hypertension ( P=0.013 ) compared with the other groups . However , there was no significant difference in LA conduction velocity and atrial effective refractory period . Q4 had the greatest LA dimension ( P<0.001 ) and volume index ( P<0.001 ) , and lowest LA appendage‐emptying velocity ( P<0.032 ) and LA voltage ( P<0.001 ) compared with the others . For 13.1±7.5 months , the classification based on the PR interval was a significant predictor of AF recurrence after RFCA of AF ( HR=1.969 , 95 % CI 1.343 to 2.886 , P=0.001 ) . Conclusions The PR interval was closely associated with advanced LA remodeling due to AF , and had a noninvasive significant predictive value of clinical recurrence of AF after RFCA Background —The optimal ablation strategy for persistent atrial fibrillation ( AF ) remains unclear . Methods and Results —This multicentre r and omized study compared circumferential pulmonary vein ablation+linear ablation ( control arm ) versus circumferential pulmonary vein ablation+linear ablation+complex fractionated atrial electrogram ( CFAE ) ablation ( CFAE arm ) in patients with persistent AF .  Circumferential pulmonary vein ablation was performed followed by roof and mitral isthmus ablation , before CFAE ablation in the CFAE arm . Ablation strategy was maintained at the first redo procedure . Sixty-five patients were recruited in each arm . The mean age was 61±10 years , 75 % were men , median AF duration was 2 years , 42 % had long-lasting persistent AF , 68 % had associated cardiovascular disease , mean left atrial dimension was 46±6 mm , and median CHA2DS2-VASc score was 2 .  Ablation and procedure times were significantly longer in the CFAE arm ( 70±20 versus 55±17 ; 201±35 versus 152±45 minutes ; P<0.005 ) . After a mean follow-up of 35±5 months , single-procedural success off antiarrhythmic drugs at 12 months ( CFAE : 30/65 [ 46 % ] versus control : 37/65 [ 57 % ] ; P=0.29 ) and multiprocedural success ( CFAE : 51/65 [ 78 % ] versus control : 52/65 [ 80 % ] ; P=1.0 ) were not significantly different . At the first redo procedure , patients in the CFAE arm had a higher incidence of organized atrial tachycardia/flutter ( 24/33 [ 73 % ] versus 11/31 [ 35 % ] ; P=0.005 ) and gap-related macro – re-entrant flutter ( 8/33[24 % ] versus 1/31[3 % ] ; P=0.03 ) . Early recurrence of atrial arrhythmia was an independent predictor of late recurrence . Conclusions —CFAE ablation did not confer incremental benefit when performed in addition to circumferential pulmonary vein ablation and linear ablation . It was associated with a higher incidence of gap-related flutter . Clinical Trial Registration —URL : http://www . clinical trials.gov . Unique identifier : NCT01711047 BACKGROUND The aims of the study are 1 ) to assess antiarrhythmic prophylaxis efficacy during the first 2 months after  radiofrequency ablation ( ARF ) due to AF ; 2 ) to define risk factors for early AF recurrence ( EAFR ) after ARF ; 3 ) to determine the long-term follow-up results and risk factors for late AF recurrence ( LAFR ) . METHODS A total number of 210 consecutive patients who had undergone ARF due to AF were analyzed . Patients were r and omized into three groups : Group 1 ( G1 ) , without any anti-arrhythmic drug ( AAD ) ; Group 2 ( G2 ) , with amiodarone or sotalol ; Group 3 ( G3 ) , with last ineffective AAD . The study was design ed to analyze two periods : short-term observation , the first 2 months after ARF ; and at least 2 years of long-term follow-up . RESULTS After 2 months , clinical data were collected from 171 patients ( 123 males , mean age of 50.3 years ; persistent AF in 19.8 % ; lone AF in 36.6 % ) .  Sinus rhythm ( SR ) was maintained in 84 ( 49.1 % ) patients ; 35 ( 20.4 % ) patients presented with a single episode of AF , 39 ( 23 % ) patients experienced a reduction in number of AF episodes , and 13 ( 7.5 % ) patients showed no improvement . No predisposing factor for early recurrence was found . After a mean follow-up of 55 months , clinical data were collected in 137 patients , of which 47 ( 34 % ) maintained SR . Those more likely to sustain SR were : males ( 82.9 % vs. 62.2 % ; p = 0.018 ) , younger patients ( 44.8 ± 12.7 vs. 52.5 ± 9.9 ; p = 0.0001 ) , patients with smaller left atrium diameter ( 4.05 ± ± 0.49 cm vs. 4.25 ± 0.51 cm ; p = 0.04 ) , and those without any AF recurrence during the first 2 months after ARF ( 78.7 % vs. 35.6 % ; p < 0.0001 ) . In the multivariable analysis , the independent risk factors for LAFR were hypertension ( p < 0.001 ) and persistent AF ( p = 0.014 ) . CONCLUSIONS Antiarrhythmic prophylaxis does not affect the number of AF recurrences during the first 2 months after ablation . SR maintenance during a blanking period after AF ablation is a positive prognostic factor in long-term follow-up . Persistent AF and hypertension are independent risk factors for late AF recurrence after pulmonary vein isolation Aims The choice between initiating a non-vitamin K antagonist oral anticoagulant ( NOAC ) and a vitamin K antagonist ( VKA ) in patients with atrial fibrillation ( AF ) may be challenging . To assist in this decision , we developed a risk score to identify patients for whom a therapeutic benefit of NOACs over VKA is predicted . Methods and results ENGAGE AF-TIMI 48 was a r and omized clinical trial of edoxaban vs. warfarin in 21 105 patients with AF . Cox proportional hazard models identified factors associated with a serious net clinical outcome ( NCO ) of disabling stroke , life-threatening bleeding , and all-cause mortality in VKA naïve patients from the warfarin arm . These were used to develop an integer risk score . Performance was assessed by C-indices and validation by bootstrapping . Kaplan-Meier analyses were stratified by three score categories and treatment arm . Over a median of 2.7 years , 457  NCO events occurred in 2898 patients with a total person-time of 7549.5 years ( 6.05%/year ) . The risk prediction model ( C = 0.693 ) for the NCO was translated into a 17-point integer score , with annualized event rates for the low , intermediate , and high-risk categories in the warfarin arm of 3.5 % , 9.9 % , and 20.8 % , respectively . Therapeutic benefit of higher- and lower-dose edoxaban over warfarin was demonstrated in the high- and intermediate-risk , with equal benefit in the low-risk categories ( P-interaction 0.008 and 0.014 , respectively ) . Conclusion In VKA naive patients with AF , the TIMI-AF score can assist in the prediction of a poor composite outcome and guide selection of anticoagulant therapy by identifying a differential clinical benefit with a NOAC or VKA BACKGROUND Patients with a variety of clinical presentations undergo atrial fibrillation ( AF ) ablation .  Long-term ablation success rates can vary considerably . OBJECTIVE The purpose of this study was to develop a clinical scoring system to predict long-term freedom from AF after ablation . METHODS We retrospectively derived the scoring system on a development cohort ( DC ) of 1125 patients undergoing AF ablation  and tested it prospect ively in a test cohort ( TC ) of 937 patients undergoing AF ablation .  RESULTS The demographics of the DC patients were as follows : age 62.3 ± 10.3 years , male sex 801 ( 71.2 % ) , left atrial size 4.30 ± 0.69 cm , paroxysmal AF 348 ( 30.9 % ) , number of drugs failed 1.3 ± 1.1 , hypertension  525 ( 46.7 % ) , diabetes 100 ( 8.9 % ) , prior stroke/transient ischemic attack 78 ( 6.9 % ) , prior cardioversion 528 ( 46.9 % ) , and CHADS2 score 0.87 ± 0.97 . Multivariate analysis showed 6 independent variables predicting freedom from AF after final ablation : coronary artery disease ( P = .021 ) , atrial diameter ( P = .0003 ) , age ( P = .004 ) , persistent or long-st and ing AF ( P < .0001 ) , number of antiarrhythmic drugs failed ( P < .0001 ) , and female sex ( P = .0001 ) . We created a scoring system ( CAAP-AF ) using these 6 variables , with scores ranging from 0 to 13 points . The 2-year AF-free rates by CAAP-AF scores were as follows : 0 = 100 % , 1 = 95.7 % , 2 = 96.3 % , 3 = 83.1 % , 4 = 85.5 % , 5 = 79.9 % , 6 = 76.1 % , 7 = 63.4 % , 8 = 51.1 % , 9 = 53.6 % , and ≥10 = 29.1 % . Ablation success decreased as CAAP-AF scores increased ( P < .0001 ) . The CAAP-AF score also predicted freedom from AF in the TC . The 2-year Kaplan-Meier AF-free rates by CAAP-AF scores were as follows : 0 = 100 % , 1 = 87.0 
    Output:
    
agent
This review article provides an overview on the published clinical risk scores related to outcomes of rhythm control strategy or AF progression
***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: Background —Atrioventricular nodal radiofrequency ablation ( AVNA ) with permanent ventricular pacing can be used to control rate in patients with atrial fibrillation ( AF ) . However , long-term outcomes after AVNA are uncertain , especially in light of irreversible pacemaker dependence . Methods and Results —We examined 9122 consecutive patients with AF . The outcomes in 453 patients with AVNA ( 26 % of whom underwent an implantable cardiac defibrillator implant and 37 % underwent cardiac resynchronization therapy implant ) were compared with AF patients without AVNA after propensity score 1:1 matching . During follow-up in the propensity-matched cohort ( 2.41±3.23 years , median 1.23 , quartiles 0.33–3.12 ) , 100 patients died ( yearly rate of death 6.6 % ) . Mode of death was available in 86 % of patients , which was cardiovascular in 67 % of the patients ( related to heart failure in 38 % , sudden death in 5 % , and other cardiovascular reason in 24 % ) and noncardiovascular in 33 % . AVNA in patients with AF was associated with a lower risk of mortality ( odds ratio 0.47 , 95 % confidence interval , 0.29–0.77 ; P=0.003 ) , a lower risk of cardiovascular mortality ( odds ratio = 0.41 , 95 % confidence interval 0.23–0.73 ; P=0.003 ) , and nonsignificant lower risk of stroke and thromboembolic events ( odds ratio = 0.61 , 95 % confidence interval 0.36–1.06 ; P=0.08 ) . Conclusions —In sick AF patients with multiple comorbidities  , AVNA with permanent ventricular pacing for rate control seems safe during follow-up and may be associated with lower mortality Background A prolonged PR interval is known to be a poor prognostic factor in cardiovascular disease . The aim of this study was to investigate the association between PR interval and clinical outcome in patients undergoing radiofrequency catheter ablation ( RFCA ) of atrial fibrillation ( AF ) . Methods and Results We prospect ively included 576 patients with AF ( 75.5 % male , 57.8±11.6 years old , 68.8 % paroxysmal AF ) who underwent RFCA .  We analyzed preprocedural sinus rhythm ECGs obtained in the absence of antiarrhythmic drug , and all enrolled patients were categorized into 4 groups based on the quartile values of the PR interval ( 166 , 182 , and 202 ms ) , and were analyzed according to the left atrium ( LA ) volume ( CT ; Computed tomography ) , LA voltage ( NavX ) , and clinical outcome of AF ablation . Based on quartile value of PR interval , the highest quartile of PR interval ( Q4 ; PR ≥202 ms ) was oldest ( P<0.001 ) , and most likely to have persistent AF ( P<0.001 ) and hypertension ( P=0.013 ) compared with the other groups . However , there was no significant difference in LA conduction velocity and atrial effective refractory period . Q4 had the greatest LA dimension ( P<0.001 ) and volume index ( P<0.001 ) , and lowest LA appendage‐emptying velocity ( P<0.032 ) and LA voltage ( P<0.001 ) compared with the others . For 13.1±7.5 months , the classification based on the PR interval was a significant predictor of AF recurrence after RFCA of AF ( HR=1.969 , 95 % CI 1.343 to 2.886 , P=0.001 ) . Conclusions The PR interval was closely associated with advanced LA remodeling due to AF , and had a noninvasive significant predictive value of clinical recurrence of AF after RFCA Background —The optimal ablation strategy for persistent atrial fibrillation ( AF ) remains unclear . Methods and Results —This multicentre r and omized study compared circumferential pulmonary vein ablation+linear ablation ( control arm ) versus circumferential pulmonary vein ablation+linear ablation+complex fractionated atrial electrogram ( CFAE ) ablation ( CFAE arm ) in patients with persistent AF .  Circumferential pulmonary vein ablation was performed followed by roof and mitral isthmus ablation , before CFAE ablation in the CFAE arm . Ablation strategy was maintained at the first redo procedure . Sixty-five patients were recruited in each arm . The mean age was 61±10 years , 75 % were men , median AF duration was 2 years , 42 % had long-lasting persistent AF , 68 % had associated cardiovascular disease , mean left atrial dimension was 46±6 mm , and median CHA2DS2-VASc score was 2 .  Ablation and procedure times were significantly longer in the CFAE arm ( 70±20 versus 55±17 ; 201±35 versus 152±45 minutes ; P<0.005 ) . After a mean follow-up of 35±5 months , single-procedural success off antiarrhythmic drugs at 12 months ( CFAE : 30/65 [ 46 % ] versus control : 37/65 [ 57 % ] ; P=0.29 ) and multiprocedural success ( CFAE : 51/65 [ 78 % ] versus control : 52/65 [ 80 % ] ; P=1.0 ) were not significantly different . At the first redo procedure , patients in the CFAE arm had a higher incidence of organized atrial tachycardia/flutter ( 24/33 [ 73 % ] versus 11/31 [ 35 % ] ; P=0.005 ) and gap-related macro – re-entrant flutter ( 8/33[24 % ] versus 1/31[3 % ] ; P=0.03 ) . Early recurrence of atrial arrhythmia was an independent predictor of late recurrence . Conclusions —CFAE ablation did not confer incremental benefit when performed in addition to circumferential pulmonary vein ablation and linear ablation . It was associated with a higher incidence of gap-related flutter . Clinical Trial Registration —URL : http://www . clinical trials.gov . Unique identifier : NCT01711047 BACKGROUND The aims of the study are 1 ) to assess antiarrhythmic prophylaxis efficacy during the first 2 months after  radiofrequency ablation ( ARF ) due to AF ; 2 ) to define risk factors for early AF recurrence ( EAFR ) after ARF ; 3 ) to determine the long-term follow-up results and risk factors for late AF recurrence ( LAFR ) . METHODS A total number of 210 consecutive patients who had undergone ARF due to AF were analyzed . Patients were r and omized into three groups : Group 1 ( G1 ) , without any anti-arrhythmic drug ( AAD ) ; Group 2 ( G2 ) , with amiodarone or sotalol ; Group 3 ( G3 ) , with last ineffective AAD . The study was design ed to analyze two periods : short-term observation , the first 2 months after ARF ; and at least 2 years of long-term follow-up . RESULTS After 2 months , clinical data were collected from 171 patients ( 123 males , mean age of 50.3 years ; persistent AF in 19.8 % ; lone AF in 36.6 % ) .  Sinus rhythm ( SR ) was maintained in 84 ( 49.1 % ) patients ; 35 ( 20.4 % ) patients presented with a single episode of AF , 39 ( 23 % ) patients experienced a reduction in number of AF episodes , and 13 ( 7.5 % ) patients showed no improvement . No predisposing factor for early recurrence was found . After a mean follow-up of 55 months , clinical data were collected in 137 patients , of which 47 ( 34 % ) maintained SR . Those more likely to sustain SR were : males ( 82.9 % vs. 62.2 % ; p = 0.018 ) , younger patients ( 44.8 ± 12.7 vs. 52.5 ± 9.9 ; p = 0.0001 ) , patients with smaller left atrium diameter ( 4.05 ± ± 0.49 cm vs. 4.25 ± 0.51 cm ; p = 0.04 ) , and those without any AF recurrence during the first 2 months after ARF ( 78.7 % vs. 35.6 % ; p < 0.0001 ) . In the multivariable analysis , the independent risk factors for LAFR were hypertension ( p < 0.001 ) and persistent AF ( p = 0.014 ) . CONCLUSIONS Antiarrhythmic prophylaxis does not affect the number of AF recurrences during the first 2 months after ablation . SR maintenance during a blanking period after AF ablation is a positive prognostic factor in long-term follow-up . Persistent AF and hypertension are independent risk factors for late AF recurrence after pulmonary vein isolation Aims The choice between initiating a non-vitamin K antagonist oral anticoagulant ( NOAC ) and a vitamin K antagonist ( VKA ) in patients with atrial fibrillation ( AF ) may be challenging . To assist in this decision , we developed a risk score to identify patients for whom a therapeutic benefit of NOACs over VKA is predicted . Methods and results ENGAGE AF-TIMI 48 was a r and omized clinical trial of edoxaban vs. warfarin in 21 105 patients with AF . Cox proportional hazard models identified factors associated with a serious net clinical outcome ( NCO ) of disabling stroke , life-threatening bleeding , and all-cause mortality in VKA naïve patients from the warfarin arm . These were used to develop an integer risk score . Performance was assessed by C-indices and validation by bootstrapping . Kaplan-Meier analyses were stratified by three score categories and treatment arm . Over a median of 2.7 years , 457  NCO events occurred in 2898 patients with a total person-time of 7549.5 years ( 6.05%/year ) . The risk prediction model ( C = 0.693 ) for the NCO was translated into a 17-point integer score , with annualized event rates for the low , intermediate , and high-risk categories in the warfarin arm of 3.5 % , 9.9 % , and 20.8 % , respectively . Therapeutic benefit of higher- and lower-dose edoxaban over warfarin was demonstrated in the high- and intermediate-risk , with equal benefit in the low-risk categories ( P-interaction 0.008 and 0.014 , respectively ) . Conclusion In VKA naive patients with AF , the TIMI-AF score can assist in the prediction of a poor composite outcome and guide selection of anticoagulant therapy by identifying a differential clinical benefit with a NOAC or VKA BACKGROUND Patients with a variety of clinical presentations undergo atrial fibrillation ( AF ) ablation .  Long-term ablation success rates can vary considerably . OBJECTIVE The purpose of this study was to develop a clinical scoring system to predict long-term freedom from AF after ablation . METHODS We retrospectively derived the scoring system on a development cohort ( DC ) of 1125 patients undergoing AF ablation  and tested it prospect ively in a test cohort ( TC ) of 937 patients undergoing AF ablation .  RESULTS The demographics of the DC patients were as follows : age 62.3 ± 10.3 years , male sex 801 ( 71.2 % ) , left atrial size 4.30 ± 0.69 cm , paroxysmal AF 348 ( 30.9 % ) , number of drugs failed 1.3 ± 1.1 , hypertension  525 ( 46.7 % ) , diabetes 100 ( 8.9 % ) , prior stroke/transient ischemic attack 78 ( 6.9 % ) , prior cardioversion 528 ( 46.9 % ) , and CHADS2 score 0.87 ± 0.97 . Multivariate analysis showed 6 independent variables predicting freedom from AF after final ablation : coronary artery disease ( P = .021 ) , atrial diameter ( P = .0003 ) , age ( P = .004 ) , persistent or long-st and ing AF ( P < .0001 ) , number of antiarrhythmic drugs failed ( P < .0001 ) , and female sex ( P = .0001 ) . We created a scoring system ( CAAP-AF ) using these 6 variables , with scores ranging from 0 to 13 points . The 2-year AF-free rates by CAAP-AF scores were as follows : 0 = 100 % , 1 = 95.7 % , 2 = 96.3 % , 3 = 83.1 % , 4 = 85.5 % , 5 = 79.9 % , 6 = 76.1 % , 7 = 63.4 % , 8 = 51.1 % , 9 = 53.6 % , and ≥10 = 29.1 % . Ablation success decreased as CAAP-AF scores increased ( P < .0001 ) . The CAAP-AF score also predicted freedom from AF in the TC . The 2-year Kaplan-Meier AF-free rates by CAAP-AF scores were as follows : 0 = 100 % , 1 = 87.0 
    Output:
    