Objective: Cardiopulmonary exercise testing (CPET) in patients with complex congenital heart
disease (CHD) provides relevant information for clinical evaluation and risk stratification.
The goal of this retrospective study was to assess predictability of ventricular arrhythmias
during CPET for severe arrhythmic events (SAEs) later in life.
Methods: Number of premature ventricular complexes and occurrence of couplets, triplets, bigeminy,
trigeminy, and nonsustained or sustained ventricular tachycardia (VT) were recorded
from CPET data. Outcome during 36 months follow-up after CPET was recorded from medical
chart review. SAEs were defined as a composite of sudden death, aborted sudden death,
appropriate discharge of implantable cardioverter-defibrillator (ICD), hospitalization
for ventricular arrhythmias, and occurrence of nonsustained or sustained VT on Holter,
pacemaker, or ICD read.
Results: Clinical data from 371 patients (42.6% female) were analyzed. Diagnoses were single
ventricle physiology in 68, tetralogy of Fallot in 131, transposition of the great
arteries in 116, Ebstein anomaly in 35, and truncus arteriosus in 21 patients. Age
at the time of CPET was 25.0 ± 10.7 years.
The table shows the comparison of patients with and without SAEs on follow-up with
regard to ventricular rhythm disturbances during CPET. Patients with no ventricular
arrhythmia at CPET had a lower occurrence of SAEs. Frequency and mean duration of
bigeminy and trigeminy and presence of couplets and triplets were not different between
patients with and without SAEs on follow-up. No patient experienced VT during CPET.
Conclusion: Patients with complex CHD and no ventricular arrhythmia during CPET are at a slightly
lower risk for SAEs during follow-up. Severity of ventricular rhythm disturbances
did not seem to influence outcome in this cohort. Risk stratification for SAEs in
patients with complex CHD should include evaluation of rhythm disturbances during
CPET, but more sensitive markers are warranted.
|
No severe arrhythmic event
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Severe arrhythmic event
|
p-Value
|
|
Abbreviations: PVC, premature ventricular complex; std, standard deviation.
|
|
aBigeminy and trigeminy length defined as number of beats in longest episode that occurred.
|
|
No ventricular arrhythmia, N/n (%)
|
176/319 (55.2)
|
20/52 (38.5)
|
0.035
|
|
PVC number (mean ± std)
|
5.1 ± 13.2
|
10.0 ± 21.3
|
0.115
|
|
Bigeminy, N/n (%)
|
14/319 (4.4)
|
3/52 (5.8)
|
0.717
|
|
Bigeminy lengtha (mean ± std)
|
12.1 ± 14.6
|
17.0 ± 9.2
|
0.587
|
|
Trigeminy, N/n (%)
|
3/319 (0.9)
|
2/52 (3.9)
|
0.146
|
|
Trigeminy lengtha (mean ± std)
|
26.7 ± 29.0
|
3 ± 0
|
0.354
|
|
Couplets, N/n (%)
|
30/319 (9.4)
|
10/52 (19.2)
|
0.186
|
|
Triplets, N/n (%)
|
6/319 (1.9)
|
1/52 (1.9)
|
1
|
