%0 Journal Article %T Atrial Fibrillation: New Horizons. %A Chi-Tai Kuo %A Nazar Luqman %A Kuo-Hung Lin %A Ying-Shiung Lee %J Chang Gung Medical Journal %D 2003 %I %X Atrial fibrillation (AF) is the most common cardiac arrhythmia seen in clinical practice.The understanding of the pathophysiology of AF has changed drastically during the last severaldecades. Recent observations have challenged the concept of the multiple circuit reentrymodel in favor of single focus or single circuit reentry models. Atrial electrical dysfunctionprovides a favorable substrate and transmembrane ionic currents are key determinants.Interest has also been generated in the role of angiotensin converting enzyme (ACE) inhibitionin reversing the electrical and structural remodeling. Reverting to the sinus rhythmseems to be the best way for reverse remodeling of atria during atrial fibrillation.Antiarrhythmic drugs (AADs) are only modestly effective. Of these amiodarone seems toprovide the most benefits. Drugs like verapamil and ACE inhibitors may also help as adjuvanttherapies in the reverse remodeling of atria. Nonpharmacological methods have beenused to control both rate and rhythm for patients with AF. Recently, there has been a surge ininterest to focal ablation of atrial foci. Focal sources of AF are commonly found in pulmonaryveins (PV). Ablation in pulmonary veins through identification of the earliest endocardialactivation has met with variable success. Anatomical approaches have involved circumferentialradiofrequency ablation of pulmonary vein ostia using novel techniques such asballoon based circumferential ultrasound ablation system and circular cryoablation catheter.Most recently the segmental approach is preferred because the myocardial fibers surroundingthe PV are not continuous. Segments where musculature is present can be identifiedusing high frequency depolarization signals recorded through multi-electrode loop catheteror even conventional catheters. %K atrial fibrillation %K atrial remodeling %K radiofrequency ablation %K pulmonary vein %U http://memo.cgu.edu.tw/cgmj/2610/261001.pdf