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 ?
Techniques, evaluation, and consequences of linear block at the left atrial roof in paroxysmal atrial fibrillation: a prospective randomized study.
BACKGROUND There are no reports describing the technique , electrophysiological evaluation , and clinical consequences of complete linear block at roofline joining the superior pulmonary veins ( PVs ) in patients with paroxysmal atrial fibrillation ( AF ) . METHODS AND RESULTS Ninety patients with drug-refractory paroxysmal AF undergoing radiofrequency ablation  were prospect ively r and omized into 2 ablation strategies : ( 1 ) PV isolation ( n=45 ) or ( 2 ) PV isolation in combination with linear ablation joining the 2 superior PVs ( roofline ; n=45 ) . In both groups , the cavotricuspid isthmus , fragmented peri-PV-ostial electrograms , and spontaneous non-PV foci were ablated . Roofline ablation was performed at the most cranial part of the left atrium ( LA ) with complete conduction block demonstrated during LA appendage pacing by the online mapping of continuous double potential and an activation detour propagating around the PVs to activate caudocranially the posterior wall of the LA . The effect of ablation at the LA roof was evaluated by the change in fibrillatory cycle length , termination and noninducibility of AF , and clinical outcome . PV isolation was achieved in all patients with no significant differences in the radiofrequency duration , fluoroscopy , or procedural time between the groups . Roofline ablation required 12+/-6 ( median 11 , range 3 to 25 ) minutes of radiofrequency energy delivery with a fluoroscopic duration of 7+/-2 minutes and was performed in 19+/-7 minutes . Complete block was confirmed in 43 patients ( 96 % ) and result ed in an activation delay that was shorter circumventing the left than the right PVs during LA appendage pacing ( 138+/-15 versus 146+/-25 ms , respectively ; P=0.01 ) . Roofline ablation result ed in a significant increase in the fibrillatory cycle length ( 198+/-38 to 217+/-44 ms ; P=0.0005 ) , termination of arrhythmia in 47 % ( 8/17 ) , and subsequent noninducibility of AF in 59 % ( 10/17 ) of the patients inducible after PV isolation . However , LA flutter , predominantly perimitral , could be induced in 10 patients ( 22 % ) after roofline ablation . At 15+/-4 months , 87 % of the roofline group and 69 % with PV isolation alone are arrhythmia free without antiarrhythmics ( P=0.04 ) . CONCLUSIONS This prospect i ve r and omized study demonstrates the feasibility of achieving complete linear block at the LA roof . Such ablation result ed in the prolongation of the fibrillatory cycle , termination of AF , and subsequent noninducibility and is associated with an improved clinical outcome compared with PV isolation alone
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 ?