Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
HOW TO MEASURE AV NODAL REFRACTORINESS IN THE PRESENCE OF VERAPAMIL, AMIODARONE, DIGOXIN, AND DILTIAZEM
Autore:
STARK G; KASPER K; SCHULZEBAUER C; STARK U; DECRINIS M; TRITTHART HA;
Indirizzi:
KARL FRANZENS UNIV GRAZ,DEPT INTERNAL MED,AUENBRUGGERPL 15 A-8036 GRAZ AUSTRIA KARL FRANZENS UNIV GRAZ,DEPT MED PHYS & BIOPHYS A-8036 GRAZ AUSTRIA
Titolo Testata:
PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY
fascicolo: 2, volume: 19, anno: 1996,
pagine: 157 - 164
SICI:
0147-8389(1996)19:2<157:HTMANR>2.0.ZU;2-W
Fonte:
ISI
Lingua:
ENG
Soggetto:
CHRONIC ATRIAL-FIBRILLATION; GUINEA-PIG HEARTS; ATRIOVENTRICULAR-CONDUCTION; CHANNEL BLOCK; MECHANISM; EFFICACY; EXERCISE; SAFETY; RABBIT; LONG;
Keywords:
VERAPAMIL; AMIODARONE; DIGOXIN; DILTIAZEM; ATRIOVENTRICULAR CONDUCTION TIME; EFFECTIVE REFRACTORY PERIOD;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
27
Recensione:
Indirizzi per estratti:
Citazione:
G. Stark et al., "HOW TO MEASURE AV NODAL REFRACTORINESS IN THE PRESENCE OF VERAPAMIL, AMIODARONE, DIGOXIN, AND DILTIAZEM", PACE, 19(2), 1996, pp. 157-164

Abstract

On the AV node the negative dromotropic action of verapamil, amiodarone, digoxin, and diltiazem is known to be rate dependent. The effective refractory period of the AV node (AV-ERP) at a short cycle length isrelated to the AV conduction at that cycle length. We investigated how the number of stimuli during the conditioning train (S-1) (during measurement of refractoriness at a high pacing rate [cycle length = 180 ms]) might influence the AV-ERP in isolated guinea pig hearts in a Langendorff preparation. Verapamil (10 nM), amiodarone (10 nM), digoxin (0.6 nM), and diltiazem (30 nM) caused a comparable prolongation of theAV conduction time (AVCT). All four drugs caused a significant prolongation of the AV-ERP when evaluated by a standard stimulation protocolwith a conditioning train of 10 stimuli (10 S-1) at a pacing cycle length of 180 ms followed by the test stimulus (S-2). When the number ofstimuli during the conditioning train (S-1) was increased (>10), until the prolongation of AVCT reached steady state, the AV-ERP in the presence of verapamil (132 +/- 4 vs 141 +/- 3 ms; P < 0.05, mean +/- S.E.M.) and diltiazem (143 +/- 3 vs 151 +/- 3 ms; P < 0.05) was prolonged significantly further. These results indicate that the effect of drugson AV-ERP should be measured with a modified stimulation protocol, whereby the number of conditioning stimuli is comparable to the time constant characterizing the prolongation of AVCT at fast pacing rates.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/04/20 alle ore 09:38:25