14th International Congress
THE "NEW FRONTIERS"
OF ARRHYTHMIAS 2000

Jan. 29 - Feb. 5, 2000
Marilleva, Trento, Italy

RT-90

Calcium-channel-blockers and efficacy of external cardioversion of persistent atrial fibrillation. Prevention of electrical remodeling?

Giovanni Luca Botto, Roberto Bonatti, Giuseppe De Nittis, Mario Susta, Franco Tettamanti, Alessandro Politi, Tiziana Broffoni, Giovanni Ferrari.
Department of Cardiology, S. Anna Hospital, Como, Italy

Abstract

Atrial fibrillation (AF) is a self-perpetuating arrhythmia causes electrophysiological changes that are mediated by rate-induced intracellular calcium overload. Calcium-channel-blockers (CCBs) could be effective in preventing atrial electrical remodeling.

We evaluate the effect of the concomitant use of CCBs on efficacy of electrical cardioversion (EC) of persistent AF and on early AF relapses after successful EC.

Four-hundred-thirthy-seven consecutive patients (pts) (mean age 62±12 years), NYHA class I-II, experienced EC for permanent AF (mean arrhythmia duration 96±129 days). One-hundred-thirty-five pts (31%) were treated with CCBs before EC and 48 hours after (Group A), while 302 pts (69%) didn’t receive them (Group B). Pts with AD > 72 hours were anticoagulated for 3 weeks prior to EC and for 4 weeks after. We define EC technical failure (TF) the inability of interrupting AF, and EC clinical failure (CF) early relapse of AF 48 hour after successful EC.

The two groups were comparable in terms of clinical variable and concomitant use of antiarrhythmic drugs. The prevalence of arterial hipertension (HTx) or coronary disease (CD) was higher in Group A pts (HTx 49/135 pts, 36% vs 74/302 pts, 25%; p<0.05, CD 18/135 pts, 13% vs 15/302 pts, 5%; p<0.0001). TF was lower in pts who received CCBs (Group A 5/135 pts, 4% vs Group B 30/302 pts, 10%; p=0.043) while no differences were detected between the two groups concerning CF (Group A 20/135 pts, 15% vs Group B 39/302 pts, 13%; p=NS). Only one patient (0.2%) experienced an embolic event 37 hours after successful EC while he was correctly anticoagulated. A pre-treatment with CCBs is useful in reducing technical failure of persistent AF, while no effects are detectable on the prevention of early relapses of the arrhythmia after successful EC. Randomized studies are mandatory to confirm the present data.

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