Alterations in physiologic properties induced by pharmacologic agents may provide useful data to clarify the mechanism of atrial flutter (AF) inman. In 15 pts, all with common type of AF, we performed one or more drug tests using: 1) Verapamil (V), to abolish abnormal automaticity like triggered activity; 2) Edrophonium chloride (EC), a cholinergic compound to shorten atrial refractoriness; 3) propaphenon (P), which has been shown to prolong atrial conductionand refractoriness. V, 0.10 mg/Kg i.v. in 5 pts (average AF cycle length 248 msec ± 11) and EC, 0.15 mg/Kg i.v. in 6 pts (average cycle length 246 msec ± 14), neither terminated AF nor changed AF cycle length significantly. P, 1.5 mg/Kg i.v. in 8 pts (average AF Cycle length 236 ms ± 25), always increased AF cycle length (average increase 62 msec, that is 26.2% of the base cycle).Thespite the complexity of drug action inman, these results are in favor of a reeentry circuit as electrogenetic mechanism of common AF.
Effects of Pharmacological Agents in the Study of Atrial Flutter Mechanism
Kirchner, Michele;
1984-01-01
Abstract
Alterations in physiologic properties induced by pharmacologic agents may provide useful data to clarify the mechanism of atrial flutter (AF) inman. In 15 pts, all with common type of AF, we performed one or more drug tests using: 1) Verapamil (V), to abolish abnormal automaticity like triggered activity; 2) Edrophonium chloride (EC), a cholinergic compound to shorten atrial refractoriness; 3) propaphenon (P), which has been shown to prolong atrial conductionand refractoriness. V, 0.10 mg/Kg i.v. in 5 pts (average AF cycle length 248 msec ± 11) and EC, 0.15 mg/Kg i.v. in 6 pts (average cycle length 246 msec ± 14), neither terminated AF nor changed AF cycle length significantly. P, 1.5 mg/Kg i.v. in 8 pts (average AF Cycle length 236 ms ± 25), always increased AF cycle length (average increase 62 msec, that is 26.2% of the base cycle).Thespite the complexity of drug action inman, these results are in favor of a reeentry circuit as electrogenetic mechanism of common AF.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
