Jm. Alegret et al., Effects of thrombolysis in the evolution of right bundle-branch block complicating an acute anterior myocardial infarction, ACT CARDIOL, 56(5), 2001, pp. 297-301
Introduction - There is scant information about the effects of thrombolysis
in the evolution of right bund(e-branch block (RBBB) in the setting of acu
te anterior myocardial infarction. The aim of this study has been to analys
e these effects and its impact on prognosis.
Methods - We studied 54 patients who presented a RBBB related to an acute a
nterior myocardial infarction. We defined two groups: those who received th
rombolytic treatment and those who did not. We analysed the evolution of RB
BB (transience, moment of onset, moment of disappearance) and its relations
hip with in-hospital mortality. Twenty-one patients (39%) received thrombol
ytic treatment (group T) and 33 patients (61%) (group NT) did not.
Results - The incidence of late appearance (> 6 h) of RBBB was less frequen
t in group T compared ;with group NT (10% vs. 33%, p = 0.04). The incidence
of transient block was similar in the two groups (57% vs. 45%, p ns). Howe
ver, early disappearance of RBBB (in < 6 hours) was more common in group T
than in group NT (33% vs. 9%, p = 0.04). Mortality was higher in patients w
ith RBBB present at 24 h after admission) than in those with RBBB resolved
in less than 24 hours (in group NT 55% vs. 8%, p = 0.02 and in group T 50%
vs. 0%, p = 0.02, respectively).
Conclusions - Thrombolysis seems to influence the moment of onset and disap
pearance of RBBB by promoting its early disappearance and avoiding its late
appearance. Disappearance of RBBB is associated with a better prognosis.