TY - JOUR
T1 - Effects of verapamil and ibutilide on atrial fibrillation and postfibrillation atrial refractoriness
AU - Sticherling, Christian
AU - Hsu, William
AU - Tada, Hiroshi
AU - Bares, Anton C.
AU - Oral, Hakan
AU - Pelosi, Frank
AU - Knight, Bradley P.
AU - Strickberger, S. Adam
AU - Morady, Fred
PY - 2002
Y1 - 2002
N2 - Introduction: Early recurrence of atrial fibrillation (AF) after cardioversion may be related to shortening of the atrial effective refractory period (ERP). This study compared the effects of verapamil and ibutilide on AF cycle length (AFCL), atrial ERP, and susceptibility to recurrent AF. Methods and Results: In 33 adults, the atrial ERP was measured at basic drive CLs of 350 and 500 msec before and after a brief episode of pacing-induced AF. During AF, verapamil, ibutilide, or saline was infused in 11 patients each. Shortening of the post-AF atrial ERP was attenuated by verapamil and prevented by ibutilide. AFCL shortened by 32 ± 21 msec in the verapamil group (P < 0.01), prolonged by 44 ± 14 msec in the ibutilide group (P < 0.001), and did not change in the control group. AF converted to sinus rhythm within 10 minutes less often after verapamil (0%) than after ibutilide (82%) or than in the control group (73 %). Post-AF, AF lasting > 10 minutes was induced more often in the verapamil group than in the ibutilide group (26% vs 0%; P = 0.01). Another 10 patients received verapamil or ibutilide in the absence of AF. Atrial ERP was unchanged after verapamil and prolonged after ibutilide. Conclusion: Verapamil shortens AFCL and impedes the conversion of induced AF, whereas ibutilide prolongs AFCL and does not impede the early conversion of induced AF. Ibutilide is more effective than verapamil in preventing post-AF shortening of the atrial ERP and reducing the susceptibility toward reinduction of AF.
AB - Introduction: Early recurrence of atrial fibrillation (AF) after cardioversion may be related to shortening of the atrial effective refractory period (ERP). This study compared the effects of verapamil and ibutilide on AF cycle length (AFCL), atrial ERP, and susceptibility to recurrent AF. Methods and Results: In 33 adults, the atrial ERP was measured at basic drive CLs of 350 and 500 msec before and after a brief episode of pacing-induced AF. During AF, verapamil, ibutilide, or saline was infused in 11 patients each. Shortening of the post-AF atrial ERP was attenuated by verapamil and prevented by ibutilide. AFCL shortened by 32 ± 21 msec in the verapamil group (P < 0.01), prolonged by 44 ± 14 msec in the ibutilide group (P < 0.001), and did not change in the control group. AF converted to sinus rhythm within 10 minutes less often after verapamil (0%) than after ibutilide (82%) or than in the control group (73 %). Post-AF, AF lasting > 10 minutes was induced more often in the verapamil group than in the ibutilide group (26% vs 0%; P = 0.01). Another 10 patients received verapamil or ibutilide in the absence of AF. Atrial ERP was unchanged after verapamil and prolonged after ibutilide. Conclusion: Verapamil shortens AFCL and impedes the conversion of induced AF, whereas ibutilide prolongs AFCL and does not impede the early conversion of induced AF. Ibutilide is more effective than verapamil in preventing post-AF shortening of the atrial ERP and reducing the susceptibility toward reinduction of AF.
KW - Atrial fibrillation
KW - Atrial refractoriness
KW - Ibutilide
KW - Verapamil
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U2 - 10.1046/j.1540-8167.2002.00151.x
DO - 10.1046/j.1540-8167.2002.00151.x
M3 - Article
C2 - 11900290
AN - SCOPUS:0036198437
SN - 1045-3873
VL - 13
SP - 151
EP - 157
JO - Journal of cardiovascular electrophysiology
JF - Journal of cardiovascular electrophysiology
IS - 2
ER -