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<h5 class="section-title" id="d14520467e388">Objectives</h5>
<p id="P1">The study objective was to determine the predictors of new-onset arrhythmia
among
infants with single-ventricle anomalies during the post-Norwood hospitalization and
the association of those arrhythmias with postoperative outcomes (ventilator time
and length of stay) and interstage mortality.
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<h5 class="section-title" id="d14520467e393">Methods</h5>
<p id="P2">After excluding patients with preoperative arrhythmias, we used data from
the Pediatric
Heart Network Single Ventricle Reconstruction Trial to identify risk factors for tachyarrhythmias
(atrial fibrillation, atrial flutter, supraventricular tachycardia, junctional ectopic
tachycardia, and ventricular tachycardia) and atrioventricular block (second or third
degree) among 544 eligible patients. We then determined the association of arrhythmia
with outcomes during the post-Norwood hospitalization and interstage period, adjusting
for identified risk factors and previously published factors.
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<h5 class="section-title" id="d14520467e398">Results</h5>
<p id="P3">Tachyarrhythmias were noted in 20% of subjects, and atrioventricular block
was noted
in 4% of subjects. Potentially significant risk factors for tachyarrhythmia included
the presence of modified Blalock–Taussig shunt (
<i>P</i> = .08) and age at Norwood (
<i>P</i> = .07, with risk decreasing each day at age 8–20 days); the only significant
risk
factor for atrioventricular block was undergoing a concomitant procedure at the time
of the Norwood (
<i>P</i> = .001), with the greatest risk being in those undergoing a tricuspid valve
procedure.
Both tachyarrhythmias and atrioventricular block were associated with longer ventilation
time and length of stay (
<i>P</i><.001 for all analyses). Tachyarrhythmias were not associated with interstage
mortality;
atrioventricular block was associated with mortality among those without a pacemaker
in the unadjusted analysis (hazard ratio, 2.3;
<i>P</i> = .02), but not after adding covariates.
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<h5 class="section-title" id="d14520467e418">Conclusions</h5>
<p id="P4">Tachyarrhythmias are common after the Norwood procedure, but atrioventricular
block
may portend a greater risk for interstage mortality.
</p>
</div><p id="P5">Atrioventricular block, but not tachyarrhythmia, is associated with
increased mortality
after the Norwood procedure.
</p><p id="P6">
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<img alt="" class="figure" src="/document_file/a35c1300-e91b-4ad4-b353-a55b4a7f5649/PubMedCentral/image/nihms835372u1.jpg"/>
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