INTRODUCTION: @entity907 characterized by @entity551 and @entity1168 . The presence of @entity7129 along with @entity713 during @entity1163 in @entity1 with @entity907 has not been described previously. METHODS AND RESULTS: Two female @entity1 (18 and 16 years old) with recurrent @entity7129 at the time of @entity1163 are described. @entity1 1 had recurrent episodes of @entity1163 . During one of these episodes, which occurred while she was being monitored, @entity7129 along with high-grade @entity713 was seen at the time of @entity1163 and @entity551 . @entity1 2 had a history of recurrent @entity1163 and @entity410 . During one of these episodes, she was documented to have ventricular asystole lasting for about 39 seconds. The sinus rate was 480 msec at the beginning, before slowing down to 960 msec prior to restoration of sinus rhythm with 1:1 AV conduction. The same scenario was repeated during head-up tilt testing. Both @entity1 were treated successfully with oral @entity7306 and, during a follow-up of 28 months and 9 months, have remained symptom-free. CONCLUSION: Sinus acceleration along with high-grade @entity713 during @entity1163 and @entity551 can occur in some @entity1 with @entity907 . The exact mechanism of this phenomenon is unclear.

@entity7129 with XXXX : an unusual presentation during @entity907 .

@entity1 :: ('9606', 'Species') :: ['patients', 'Patient'] @entity410 :: ('MESH:D012640', 'Disease') :: ['seizure'] @entity907 :: ('MESH:D019462', 'Disease') :: ['Neurocardiogenic (vasovagal) syncope is', 'neurocardiogenic syncope'] @entity713 :: ('MESH:D054537', 'Disease') :: ['AV block'] @entity1163 :: ('MESH:D013575', 'Disease') :: ['syncope'] @entity7306 :: ('MESH:D004206', 'Chemical') :: ['disopyramide'] @entity7129 :: ('MESH:D013616', 'Disease') :: ['sinus tachycardia', 'syncope and documented sinus tachycardia'] @entity551 :: ('MESH:D007022', 'Disease') :: ['hypotension'] @entity1168 :: ('MESH:D001919', 'Disease') :: ['bradycardia']
@entity713 :: (MESH:D054537,Disease) :: ['atrioventricular block']
