[Acute effects of propafenone in patients with ventricular pre-excitation].

Abstract

PURPOSE:

To evaluate the electrophysiological effects of intravenous propafenone in the anterograde and retrograde effective refractory period of the accessory pathways (AP), in patients with Wolff-Parkinson-White syndrome.

METHODS:

Forty symptomatic patients were studied. All patients were undergone to electrophysiologic study at baseline and after IV propafenone (2.0mg/kg). Drug effects were analysed according to the basal state of the anterograde and retrograde effective refractory periods of the AP > < 270ms.

RESULTS:

The mean anterograde and retrograde effective refractory periods of the AP were 275 +/- 76ms and 264 +/- 44ms at the control and 462 +/- 190ms and 438 +/- 184ms after drug respectively (p < 0.01 in both situations). The mean anterograde effective refractory period of the AV node was 236 +/- 40ms (control) and 276 +/- 57ms (post-drug)- p < 0.05. The mean atrial and right ventricular effective refractory period in the control were 210 +/- 23ms and 240 +/- 34ms passing to 215 +/- 24ms and 250 +/- 40 ms after drug respectively (p = ns). After drug, complete anterograde and retrograde block of the AP, occurred in 15 (42%) and 12 (35%) patients respectively. Out of 15 patients with complete anterograde block of the AP, 11 had anterograde effective refractory period of the AP > 270ms and 4, < 270ms (p < 0.02). Out of 12 patients with complete retrograde block of the AP after drug, 4 had retrograde effective refractory period > 270ms and 8, < 270ms (p: ns).

CONCLUSION:

Propafenone caused significant increase in the anterograde and retrograde effective refractory periods of the AP. There was a tendency of the drug to show better effectiveness in patients with anterograde effective refractory period of the AP > 270ms. This results were not seen in relation to the retrograde effective refractory period of the AP.

• Authors: I G Maia, F Cruz Filho, M L Fagundes, L H Loyola, J Pimenta, A M Lorga
• Journal: Arquivos brasileiros de cardiologia (Arq Bras Cardiol) Vol. 61 Issue 1 Pg. 23-6 (Jul 1993) ISSN: 0066-782X [Print] Brazil
• Vernacular Title: Efeitos agudos da propafenona em pacientes com pré-excitação ventricular.
• PMID: 8285860 (Publication Type: Clinical Trial, Comparative Study, English Abstract, Journal Article)

Chemical References

• Propafenone

Topics

• Adolescent
• Adult
• Atrioventricular Node (abnormalities, drug effects)
• Electrocardiography
• Female
• Heart Block (chemically induced)
• Humans
• Male
• Middle Aged
• Propafenone (administration & dosage, pharmacology)
• Tachycardia, Paroxysmal (chemically induced)
• Wolff-Parkinson-White Syndrome (drug therapy, physiopathology)