Contribution This systematic review found that radiofrequency ablation after a failed drug course maintained sinus rhythm more often than continuation of drug therapy alone .
The benefits of maintaining sinus rhythm with antiarrhythmic drugs appeared to be offset by the serious adverse effects of the drugs .
Context Is radiofrequency catheter ablation a better alternative than medical therapy for patients with atrial fibrillation ?
The Editors Atrial fibrillation is the most common sustained arrhythmia in clinical practice ( 1 ) .
Its prevalence increases with age , from 0.1 % in people younger than 55 years to more than 9 % by 80 years of age ( 2 ) .
The heavy burden of atrial fibrillation on morbidity , mortality , and health care re sources creates a pressing need for novel approaches to management .
In some patients , adequate pharmacologic slowing of the ventricular response rate ( a rate-control strategy ) is sufficient to control symptoms .
However , many patients remain symptomatic from the lack of organized atrial contraction and the persistent irregularity of the ventricular response in atrial fibrillation .
In such patients , the appropriate treatment is restoration of normal sinus rhythm , achieved electrically or chemically ( a rhythm-control strategy ) ( 2 ) .
Radiofrequency catheter ablation is a promising approach that offers the benefits of maintaining sinus rhythm without the adverse effects of antiarrhythmic drugs .
Catheter ablation for atrial fibrillation is based on the underst and ing that electrical activity emanating from the pulmonary veins frequently serves as a trigger for atrial fibrillation .
In the late 1990s , Hassaguerre and colleagues ( 5 ) observed that elimination of local electrograms at these foci with radiofrequency energy reduced the risk for recurrence of atrial fibrillation .
Currently , the foundation of most atrial fibrillation ablation procedures is to target and electrically isolate the pulmonary veins ( 6 ) .
This may be achieved by delivering lesions immediately outside the ostia of the pulmonary veins or along a wider area in the left atrium encircling the veins .
Additional lesion sets have been used to ablate nonpulmonary vein triggers of atrial fibrillation and to target atrial areas thought to be responsible for maintaining atrial fibrillation ( 6 ) .
These linear lesions may be created in the posterior left atrium , the roof of the left atrium , the interatrial septum , and the isthmus formed between the mitral annulus and the pulmonary vein or left atrial appendage .
At present , the Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation , put forth by the Heart Rhythm Society and endorsed by several professional organizations , states that the foundation of most atrial fibrillation ablation procedures is to target the pulmonary veins , pulmonary vein antra , or both ( 6 ) .
The panel advised us that 8-mmtip and irrigated-tip catheters are now the catheters of choice for radiofrequency ablation of atrial fibrillation in the United States .
The conventional 4-mmtip catheter is rapidly being phased out of use for this indication .
The following 3 key questions were formulated : 1 .
What is the effect of radiofrequency catheter ablation on short-term ( 6 to 12 months ) and long-term ( > 12 months ) rhythm control ; rates of congestive heart failure ; changes in the size of the left atrium and ventricle ; rates of stroke ; quality of life ; avoiding anticoagulation ; and readmissions for paroxysmal , persistent , and long-st and ing persistent ( chronic ) atrial fibrillation ?
2 .
How does the effect of radiofrequency ablation  on rhythm control differ among the various techniques used ?
3 .
What are the short- and long-term complications and harms associated with radiofrequency ablation ?
Left mitral isthmus ablation associated with PV Isolation: long-term results of a prospective randomized study.
BACKGROUND The deployment of an ablation line connecting the left inferior PV to the mitral annulus ( mitral isthmus line [ MIL ] ) enhances the efficacy of pulmonary vein disconnection ( PVD ) in preventing atrial fibrillation ( AF ) recurrences . OBJECTIVES To investigate the long-term effect of the additional linear lesion in a prospect i ve r and omized study . METHODS One hundred and eighty-seven patients ( 37 females , mean age : 55 + /- 11 years ) with paroxysmal ( 126 ) or persistent ( 61 patients ) AF , were prospect ively r and omized into two groups : PVD ( group A , 92 patients ) or PVD combined with MIL ( group B , 95 patients ) , performed by means of an irrigated-tip ablation catheter . RESULTS Successful disconnection of all PVs was achieved in all patients . A bidirectional block ( BB ) along the left atrial isthmus was obtained in 72 of 95 ( 76 % ) patients in group B , most of whom required additional RF pulses from within the distal CS . A transient ischemic attack occurred in 1 patient of group A , and a cardiac tamponade occurred in 1 patient of group B. At 1 year , 53 + /- 5 % ( group A ) and 71 + /- 5 % ( group B ) remained arrhythmia free ( P = 0.01 ) ; subgroup analysis highlights a higher improvement among patients with persistent AF ( 74 + /- 9 % vs 36 + /- 9 % ; P < 0.01 ) than what was observed in paroxysmal AF ( 76 + /- 6 % vs 62 + /- 6 % ; P < 0.05 ) ; antiarrhythmic drugs were continued in 56 % and 50 % , respectively , in groups A and B ( P = ns ) . CONCLUSIONS The addition of mitral isthmus line to the PV disconnection allows a significant improvement of sinus rhythm maintenance rate , particularly in patients with persistent AF , without the risk for major complications
Contribution This systematic review found that radiofrequency ablation after a failed drug course maintained sinus rhythm more often than continuation of drug therapy alone .
The benefits of maintaining sinus rhythm with antiarrhythmic drugs appeared to be offset by the serious adverse effects of the drugs .
Context Is radiofrequency catheter ablation a better alternative than medical therapy for patients with atrial fibrillation ?
The Editors Atrial fibrillation is the most common sustained arrhythmia in clinical practice ( 1 ) .
Its prevalence increases with age , from 0.1 % in people younger than 55 years to more than 9 % by 80 years of age ( 2 ) .
The heavy burden of atrial fibrillation on morbidity , mortality , and health care re sources creates a pressing need for novel approaches to management .
In some patients , adequate pharmacologic slowing of the ventricular response rate ( a rate-control strategy ) is sufficient to control symptoms .
However , many patients remain symptomatic from the lack of organized atrial contraction and the persistent irregularity of the ventricular response in atrial fibrillation .
In such patients , the appropriate treatment is restoration of normal sinus rhythm , achieved electrically or chemically ( a rhythm-control strategy ) ( 2 ) .
Radiofrequency catheter ablation is a promising approach that offers the benefits of maintaining sinus rhythm without the adverse effects of antiarrhythmic drugs .
Catheter ablation for atrial fibrillation is based on the underst and ing that electrical activity emanating from the pulmonary veins frequently serves as a trigger for atrial fibrillation .
In the late 1990s , Hassaguerre and colleagues ( 5 ) observed that elimination of local electrograms at these foci with radiofrequency energy reduced the risk for recurrence of atrial fibrillation .
Currently , the foundation of most atrial fibrillation ablation procedures is to target and electrically isolate the pulmonary veins ( 6 ) .
This may be achieved by delivering lesions immediately outside the ostia of the pulmonary veins or along a wider area in the left atrium encircling the veins .
Additional lesion sets have been used to ablate nonpulmonary vein triggers of atrial fibrillation and to target atrial areas thought to be responsible for maintaining atrial fibrillation ( 6 ) .
These linear lesions may be created in the posterior left atrium , the roof of the left atrium , the interatrial septum , and the isthmus formed between the mitral annulus and the pulmonary vein or left atrial appendage .
At present , the Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation , put forth by the Heart Rhythm Society and endorsed by several professional organizations , states that the foundation of most atrial fibrillation ablation procedures is to target the pulmonary veins , pulmonary vein antra , or both ( 6 ) .
The panel advised us that 8-mmtip and irrigated-tip catheters are now the catheters of choice for radiofrequency ablation of atrial fibrillation in the United States .
The conventional 4-mmtip catheter is rapidly being phased out of use for this indication .
The following 3 key questions were formulated : 1 .
What is the effect of radiofrequency catheter ablation on short-term ( 6 to 12 months ) and long-term ( > 12 months ) rhythm control ; rates of congestive heart failure ; changes in the size of the left atrium and ventricle ; rates of stroke ; quality of life ; avoiding anticoagulation ; and readmissions for paroxysmal , persistent , and long-st and ing persistent ( chronic ) atrial fibrillation ?
2 .
How does the effect of radiofrequency ablation  on rhythm control differ among the various techniques used ?
3 .
What are the short- and long-term complications and harms associated with radiofrequency ablation ?