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 ?
Circumferential pulmonary-vein ablation for chronic atrial fibrillation.
BACKGROUND We conducted a r and omized , controlled trial of circumferential pulmonary-vein ablation for the treatment of chronic atrial fibrillation . METHODS A total of 146 patients with a mean ( + /-SD ) age of 57+/-9 years who had chronic atrial fibrillation were r and omly assigned to receive amiodarone and undergo two cardioversions during the first three months alone ( the control group ) or in combination with circumferential pulmonary-vein ablation . Cardiac rhythm was assessed with daily telephonic transmissions for one year . The left atrial diameter and the severity of symptoms were assessed at 12 months . RESULTS Among the 77 patients assigned to undergo circumferential pulmonary-vein ablation , ablation was repeated because of recurrent atrial fibrillation in 26 percent of patients and atypical atrial flutter in 6 percent . An intention-to-treat analysis showed that 74 percent of patients in the ablation group and 58 percent of those in the control group were free of recurrent atrial fibrillation or flutter without antiarrhythmic-drug therapy at one year ( P=0.05 ) . Among the 69 patients in the control group , 53 ( 77 percent ) crossed over to undergo circumferential pulmonary-vein ablation for recurrent atrial fibrillation by one year and only 3 ( 4 percent ) were in sinus rhythm without antiarrhythmic-drug therapy or ablation . There were significant decreases in the left atrial diameter ( 12+/-11 percent , P<0.001 ) and the symptom severity score ( 59+/-21 percent , P<0.001 ) among patients who remained in sinus rhythm after circumferential pulmonary-vein ablation . Except for atypical atrial flutter , there were no complications attributable to circumferential pulmonary-vein ablation . CONCLUSIONS Sinus rhythm can be maintained long term in the majority of patients with chronic atrial fibrillation by means of circumferential pulmonary-vein ablation independently of the effects of antiarrhythmic-drug therapy , cardioversion , or both . The maintenance of sinus rhythm is associated with a significant decrease in both the severity of symptoms and the left atrial diameter
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 ?