D. Restoration of sinus rhythm for monophasic vs. biphasic waveforms .
Another study showed that PVI result ed in long-term restoration
Atrial fibrillation ( AF ) is a major public health problem in the United States .
More than 2.3 million Americans are estimated to have AF ( 1 ) .
The known association between AF and substantial mortality , morbidity , and health care costs compounds the effect of this condition .
Not only is the risk for death in patients with AF twice that of patients without it , but AF can result in myocardial ischemia and infa rct ion , exacerbate heart failure ( HF ) , and cause tachycardia-induced cardiomyopathy if the ventricular rate is not well-controlled ( 25 ) .
The most dreaded complication of AF is thromboembolism , especially stroke ( 6 ) .
In some patients , AF or therapies to manage this condition can severely depreciate quality of life ( 710 ) .
Furthermore , the management of AF and its complications is responsible for nearly $ 16 billion in additional costs to the U.S. health care system per year ( 11 ) .
We conducted this systematic review to evaluate the comparative safety and effectiveness of rate- versus rhythm-control strategies ;  medications used for ventricular rate control ; strict versus more lenient rate-control strategies ; nonpharmacologic rate-control therapies  versus medications ; electrical cardioversion and antiarrhythmic medications  for restoration of sinus rhythm ;  and  catheter ablation , surgical ablation , and antiarrhythmic medications  for maintenance of sinus rhythm .
A randomized controlled trial of efficacy and ST change following use of the Welch-Allyn MRL PIC biphasic waveform versus damped sine monophasic waveform for external DC cardioversion.
OBJECTIVE Biphasic waveforms have similar or greater efficacy at cardioverting atrial and ventricular arrhythmias at lower energy levels than monophasic waveforms , and cause less ST depression following defibrillation of ventricular fibrillation . No studies have investigated this effect on ST change with atrial arrhythmias . We studied the efficacy of the Welch Allyn-MRL PIC biphasic defibrillator . METHODS One hundred and thirty-nine patients undergoing elective DC cardioversion for atrial arrhythmias were r and omised to cardioversion by monophasic ( Hewlett Packard Codemaster XL ; 100 , 200 , 300 , 360 and 360J ) or biphasic ( Welch Allyn-MRL PIC ; 70 , 100 , 150 , 200 and 300J ) defibrillator . We analysed success of cardioversion after 0 and 30min , cumulative energy , number of shocks and energy at successful cardioversion . The ST change in the recorded electrocardiogram was measured at 15s after all shocks using electronic callipers . RESULTS Immediately after cardioversion 59/68 ( 86.8 % ) of the monophasic group versus 56/60 ( 93.3 % ) of the biphasic group were in sinus rhythm . Of the monophasic group , 55/67 ( 82.1 % ) remained in sinus rhythm at 30min versus 53/58 ( 91.4 % ) of the biphasic group . These differences were not significant at 0min ( P=0.35 ) or 30min ( P=0.21 ) . The biphasic group required significantly fewer shocks ( P=0.006 ) , less cumulative energy ( P<0.0001 ) and required lower total energy for successful cardioversion ( P<0.0001 ) . Of the 102 patients with electrocardiogram recordings suitable for analysis , ST segment change was greater in the monophasic group ( P=0.037 ) . CONCLUSIONS The Welch Allyn-MRL biphasic waveform for DC cardioversion results in fewer shocks , with less cumulative energy delivered and less post shock ST change than with a Hewlett Packard Codemaster XL damped sine wave monophasic waveform
D. Restoration of sinus rhythm for monophasic vs. biphasic waveforms .
Another study showed that PVI result ed in long-term restoration
Atrial fibrillation ( AF ) is a major public health problem in the United States .
More than 2.3 million Americans are estimated to have AF ( 1 ) .
The known association between AF and substantial mortality , morbidity , and health care costs compounds the effect of this condition .
Not only is the risk for death in patients with AF twice that of patients without it , but AF can result in myocardial ischemia and infa rct ion , exacerbate heart failure ( HF ) , and cause tachycardia-induced cardiomyopathy if the ventricular rate is not well-controlled ( 25 ) .
The most dreaded complication of AF is thromboembolism , especially stroke ( 6 ) .
In some patients , AF or therapies to manage this condition can severely depreciate quality of life ( 710 ) .
Furthermore , the management of AF and its complications is responsible for nearly $ 16 billion in additional costs to the U.S. health care system per year ( 11 ) .
We conducted this systematic review to evaluate the comparative safety and effectiveness of rate- versus rhythm-control strategies ;  medications used for ventricular rate control ; strict versus more lenient rate-control strategies ; nonpharmacologic rate-control therapies  versus medications ; electrical cardioversion and antiarrhythmic medications  for restoration of sinus rhythm ;  and  catheter ablation , surgical ablation , and antiarrhythmic medications  for maintenance of sinus rhythm .