Patients with late potentials on the signal averaged electrocardiogram
(SAECG) are more at risk of lethal arrhythmias in the period after acute
myocardial infarction (AMI). To assess the effect ofintravenous thrombolysis
on the incidence ofventricular late potentials, 68patients surviving a
first anteriorAMI were included in the present study: 52 patients ( 76.5%)
(43 males, 9females, mean age 5611 years) received intravenous streptokxnase
(SK) group A and 16 patients (23.5%) (12 males, 4 females,
mean age 58+10 years ) received conventional medical treatment. A time
domain SAECG, echocardiography andHottermonitoring were performed
at the time ofhospital discharge. There was no difference between group
A and groupBpatients in terms ofmean LVejectionfraction (EF) ( 55+8
us 51+11, P=NS). The incidence ofventricular late potentials was 17.3%
vs 50%ingroupA&Brespectively (P<0,01). Therewas significant differ
ence in LVEF, dyskinesia and ventricular arrhythmias between patients
with late potentials (LP) and thosewithout. Therewas also significant dif
ference in LVEF, dyskinesia and SAECG data betweenpatients who had
arrhythmic events and those who did not Thrombolysis significantly re
duces the rate oflatepotentials. The reduced rate oflatepotentials in the
present study suggests an improved ventricular stability after thrombolysis.
Since the risk ofventricular arrhythmia is higher in patients with late
potentials, this may partly explain the beneficial effects of thrombolysis
afterAMI. |
