BACKGROUND: The electrical alternans shown on an ST segment, ST alternans, is known as one of the most important predictors of @entity2224 ( @entity2224 ). It has also been reported that @entity1372 channel inhibition changes action potential configuration, especially on the repolarization phase. Thus, the @entity1372 channel blocker may produce ST alternans and trigger reentrant @entity943 . METHODS AND RESULTS: A @entity1372 channel blocker ( @entity7306 , @entity3303 , or @entity6237 ) was infused selectively into the left anterior descending coronary artery in anesthetized, open-chest @entity235 . Sixty unipolar electrograms were simultaneously recorded from the entire cardiac surface of the heart. The amplitude of ST alternans (STa) was determined as the difference in the ST-segment magnitude between 2 consecutive electrograms. We accepted the greatest STa among 60 leads for evaluation. High-dose @entity6237 (100 microg. kg-1. min-1) increased STa and evoked a spontaneous @entity2224 . The STa in high-dose @entity6237 loading (8.7+/-3.4 mV; mean+/-SEM) was significantly greater than that in @entity7306 or @entity3303 (0. 9+/-0.4 and 0.8+/-0.2 mV, P<0.05). Treatment of @entity973 ( @entity974 ) suppressed the increase in STa and the occurrence of @entity2224 evoked by @entity6237 , while @entity9690 or @entity1855 did not inhibit those. CONCLUSIONS: @entity6237 caused the ST alternans that was closely correlated to the occurrence of @entity2224 . Because the ST alternans was suppressed by @entity974 treatment, a @entity974 -sensitive current such as Ito or Isus may play an important role on this phenomenon.

Intracoronary @entity6237 induces ST alternans and reentrant @entity943 on intact @entity235 heart: A role of XXXX -sensitive current.

@entity235 :: ('9615', 'Species') :: ['dogs'] @entity1855 :: ('MESH:D014700', 'Chemical') :: ['verapamil'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity6237 :: ('MESH:D005424', 'Chemical') :: ['flecainide', 'Flecainide'] @entity974 :: ('CHEBI:34385', 'Chemical') :: ['4-AP'] @entity3303 :: ('MESH:D008012', 'Chemical') :: ['lidocaine'] @entity7306 :: ('MESH:D004206', 'Chemical') :: ['disopyramide'] @entity2224 :: ('MESH:D014693', 'Disease') :: ['VF', 'ventricular fibrillation'] @entity9690 :: ('MESH:C063968', 'Chemical') :: ['E4031'] @entity973 :: ('MESH:D015761', 'Chemical') :: ['4-aminopyridine'] @entity943 :: ('MESH:D001145', 'Disease') :: ['arrhythmia']
@entity973 :: (MESH:D015761,Chemical) :: ['4-aminopyridine']
