Abstracts | EQUINE
Atrial premature depolarisations five days post electrical
cardioversion are related to atrial fibrillation recurrence risk
in horses
I. Vernemmen, D. De Clercq, A. Decloedt, L. Vera, G. Van Steenkiste, G. van Loon
Background
The number of atrial premature depolarisations (APDs)
is a known risk factor for atrial fibrillation (AF) recurrence
in humans.
Objectives
To evaluate if the number of APDs over a 24‐h period 5
days post cardioversion predicts AF recurrence within 1
year in horses, taking the multifactorial nature of AF into
account.
Study design
Retrospective case series.
Methods
Eighty horses met these inclusion criteria: first
AF episode, no AF recurrence within 5 days post
cardioversion,
cardioversion
by
transvenous
electrical cardioversion (TVEC), 24‐h ECG recording
and echocardiographic examination 5 days post
cardioversion, no antiarrhythmic treatment during the
ECG recording and follow‐up of minimum 1 year. To
compare the APD burden between the recurrence and
non‐recurrence group a Mann–Whitney U test was used.
A multivariable survival model was built to identify
additional risk factors for AF recurrence.
Results
The patient population mainly consisted of Warmbloods
(93%). Twenty‐six horses (33%) experienced AF
recurrence within 1 year. The number of APDs (median
[range]) was significantly higher (P = 0.01) in the
recurrence group (15 [1–152]) compared with the
non‐recurrence group (7 [0–304]). In the multivariable
survival model, APDs ≥25/24 h (hazard ratio [HR] 2.9,
95% confidence interval [CI] 1.2–6.8, P = 0.02), mitral
regurgitation (HR 8.6, 95% CI 2.6–28.9, P<0.001), left
atrial active fractional area change ≤9.6% (HR 2.6, 95% CI
1.0–6.5, P = 0.04) and lower body weight (HR 0.99, 95%
CI 0.98–0.99, P = 0.001) were significantly associated
with AF recurrence.
Main limitations
This study did not evaluate early AF recurrence within 5
days. The results cannot necessarily be extrapolated to
other treatment methods, as only horses converted by
TVEC were included.
Conclusions
The APD burden 5 days post cardioversion could be
a useful predictive value for AF recurrence within 1
year in horses. However, other factors such as mitral
regurgitation and atrial contractile function must also
be taken into account.
• Volume 21 Issue 4 | December 2019 •
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