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Europace (2008) 10, 998–1003
doi:10.1093/europace/eun121
Natural history of ventricular premature contractions
in children with a structurally normal heart: does
origin matter?
Gertie C.M. Beaufort-Krol, Sebastiaan S.P. Dijkstra, and Margreet Th.E. Bink-Boelkens*
Beatrix Children’s Hospital, Division of Pediatric Cardiology, University Medical Center Groningen, University of Groningen,
Hanzeplein 1, PO Box 30.001, 9700 RB Groningen, The Netherlands
Received 10 November 2007; accepted after revision 15 April 2008; online publish-ahead-of-print 6 May 2008
KEYWORDS
Aims Premature ventricular contractions (PVCs) are thought to be innocent in children with normal
hearts, especially if they disappear during exercise. The aim of our study was to study the natural
history of PVCs in childhood and whether there is a difference between PVCs originating from the
right [premature ventricular contraction with left bundle branch block (PVC-LBBB)] or the left ventricle
[premature ventricular contraction with right bundle branch block (PVC-RBBB)].
Methods and results We evaluated children with frequent PVCs and anatomically normal hearts (n ¼
59; 35M/24F) by 12-lead ECG, echocardiography, Holter recording, and an exercise test. Age at the
first visit was 7.1 + 4.3 years (mean + SD), and follow-up was 3.1 + 3.1 years. We could evaluate
each child for 2.5 + 1.5 times. Premature ventricular contraction with left bundle branch block was
seen in 41% of the children; PVC-RBBB in 36%; and undetermined in 23%. Mean percentage PVCs in
the Holter recording decreased (14.3 + 13.7% in the age group 1–3 years to 4.8 + 7.2% in the age
group 16 years; P ¼ 0.08). Mean percentage PVC-LBBB did not change (12.3 + 21.4 vs. 11.7 +
5.5%), whereas PVC-RBBB decreased (16.3 + 4.2 to 0.6 + 1.4%; P , 0.02).
Conclusion We conclude that there is a difference in the natural history between PVC-LBBB and PVCRBBB in children with an anatomically normal heart. Premature ventricular contraction with right
bundle branch block disappears during childhood. Follow-up of these children seems not necessary. Premature ventricular contraction with left bundle branch block does not disappear and, therefore, it may
be necessary to follow these children even during adulthood.
Introduction
Frequent premature ventricular contractions (PVCs) are rare
in healthy children and young adults. They are extremely
rare in children below the age of 9 years, but also only
2–6% of older children and young adults have more than 50
PVCs/24 h.1–4 These PVCs are, in general, considered
benign, if no underlying cardiac disease is diagnosed and if
the PVCs are suppressed by exercise. Although probably
true, this benign influence of suppression by exercise is
never proved by prospective studies. The opposite, induction of ventricular arrhythmias by exercise is of course a
sign of structural or electrical heart disease, although it
was occasionally found in otherwise healthy children.5 The
natural history of PVCs in children with a structurally
normal heart seems favourable as many studies, although
* Corresponding author. Tel: þ31 50 3612800; fax: þ31 50 3614235.
E-mail address: [email protected]
with small patient numbers, show a decrease in numbers
of PVCs during follow-up and no morbidity or mortality.
The only study with a larger number of patients (n ¼ 78)
found that PVCs disappeared in 28% of the patients after a
follow-up of 72 + 32 months.6
Although probably benign, there are two reasons to hesitate to discharge children with frequent PVCs from
follow-up. First, a prolonged period of very frequent PVCs
may lead to left ventricular (LV) dilatation7 and, secondly,
PVCs originating from the right ventricle (RV) might be the
first symptom of arrhythmogenic right ventricular cardiomyopathy (ARVC). Therefore, it is advised to follow these
children at 1–2 year intervals.8
The natural history studies in children considered PVCs,
irrespective of the origin from RV or LV. However, the
origin might be of importance, especially in view of the
presence of ARVC. Therefore, we retrospectively studied
the natural history of PVCs in relation to their origin in
Published on behalf of the European Society of Cardiology. All rights reserved. & The Author 2008.
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Natural history;
Paediatrics;
Premature ventricular
contractions;
Structurally normal heart
PVCs in children with normal hearts
children with a structurally normal heart. The aim of our
study was to judge if the natural history was different for
PVCs originating from the RV or LV and if this might have
consequences for the follow-up policy.
Methods
Patients
Fifty-nine children (35 M/24 F) with PVCs were admitted to our hospital since 1975. All parents provided informed consent for clinical
evaluation.
Monitoring parameters
We evaluated the children three-yearly during follow-up by history,
physical examination, ECG, 24-h Holter recording, echocardiography, and an exercise test. The data of the children were analysed
in different age groups (1–3, 3–5, 5–8, 8–12, 12–16, and 16
years).
Electrocardiogram
Results
Patients
Age at the first visit was 7.1 + 4.3 years (mean + SD) and
follow-up was 3.1 + 3.1 years. There was no difference in
follow-up duration in the LBBB and RBBB group (4.6 + 2.6
vs. 6.2 + 3.7 years; NS). We could evaluate each child for
2.5 + 1.5 times. Most children had no complaints at all
and were referred because of an accidentally found irregular heart rate. Eight children had complaints of chest pain
or irregular heart beat. Family history was negative for
cardiac diseases. There were two first or second degree
family members with complaints of irregular heart beat.
No morbidity or mortality occurred during follow-up.
Electrocardiogram
Heart rate, frontal axis, PQ interval, QRS width, and QTc
interval were normal. Representative ECGs demonstrating
the PVC morphology (BBB and frontal axis) to illustrate the
specific type of ventricular ectopy are shown in Figure 1.
Premature ventricular contraction with left bundle branch
block was seen in 41% of the children, PVC-RBBB in 36%,
and in 23%, the origin of the PVC could not be determined.
Of the children with PVC-LBBB, 83% had an inferior axis and
17% had a superior axis.
Holter recording
Holter recording
In the Holter recording, lowest, mean, and highest heart rates were
evaluated. Premature ventricular contractions were expressed as a
percentage of the total number of QRS complexes per 24 h. It was
determined whether the PVCs were uniform or multiform, and
whether there were couplets or ventricular tachycardias (VTs). Furthermore, the heart rate above which no PVCs were present was
determined.
Lowest, mean, and highest heart rates were within normal
values. For the total group, the mean percentage PVCs
decreased from 14.3 + 13.7% in the age group 1–3 years to
4.8 + 7.2% in the age group 16 years (P ¼ 0.08). Mean percentage PVC-LBBB did not change (Figure 2; 12.3 + 21.4 vs.
11.7 + 5.5%). Mean percentage PVC-RBBB decreased from
16.3 + 4.2 to 0.6 + 1.4% (Figure 3; P , 0.02). Most children
had uniform PVCs (uniform 69%, multiform 26%, and undetermined 5%). Couplets were found in 47% of the total
group of children and consisted mostly of PVC with a
fusion beat. The group of children with couplets had a
higher percentage of PVCs than the group without couplets
(15.6 + 12.4 vs. 9.8 + 9.8%; P , 0.05). Ventricular tachycardia (maximum three beats; most PVC/fusion beat/PVC)
mostly once per 24 h was found in 20% of the children.
There was no difference in the occurrence of couplets or
VT between the PVC-LBBB and PVC-RBBB groups. Mean
heart rate at which the PVCs disappeared was not different
between the PVC-LBBB and PVC-RBBB groups. For the total
group, this heart rate was higher in the age groups 8
years than in the age groups 8 years (Figure 4; e.g. 5–8
years: 163 + 24 vs. 16 years: 130 + 36 b.p.m.; P , 0.02).
None of the children developed repetitive monomorphic
VT or sustained VT of either the right ventricular or the LV
origin during follow-up.
Echocardiography
Echocardiography was performed to exclude anatomical abnormalities and cardiomyopathy. Measurements of LV dimensions and walls
were made by two-dimensional and M-mode echocardiography on a
parasternal short-axis view using standard techniques. All measurements were performed in triplicate and averaged. Left ventricular
end-diastolic diameter (LVEDD) was measured between the endocardium of the intraventricular septum and the posterior LV wall at the
chordal level, expressed in millimeters and plotted on percentile
curves adjusted for weight.9 Left ventricular end-systolic diameter
(LVESD) was measured likewise. Shortening fraction (SF) was calculated as (LVEDD 2 LVESD)/LVEDD. Repetitive echocardiograms were
performed when the children still had .10% PVCs in the Holter
recording.
Exercise test
During ergometry (7 years; bicycle test), heart rate at rest and
during exercise was measured. Furthermore, the heart rate above
which no PVCs were found was determined. The exercise test was
finished when complaints of fatigue or ventricular arrhythmias
(couplets or VT) occurred.
Statistical analysis
Data are expressed as mean + SD. Statistical analysis was performed
with a two-tailed Student’s t-test or x2 test. A P-value ,0.05 was
considered to be statistically significant.
Echocardiography
All children had a normal anatomy of the heart with LV
dimensions that were within normal limits. No signs of cardiomyopathy or abnormalities of the RV were found. The echocardiograms at last follow-up (4.6 + 3.9 years; n ¼ 15)
showed normal LV function (SF 0.35 + 0.04).
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In a 12-lead ECG (rest; supine position), heart rate (b.p.m.), frontal
axis, PQ interval (ms), QRS width, and QTc interval were evaluated.
If PVCs were present, it was determined whether they originated
from the RV [premature ventricular contraction with left bundle
branch block (PVC-LBBB)] or from the LV [premature ventricular
contraction with right bundle branch block (PVC-RBBB)]. If possible,
the axis of the PVCs was also determined.
999
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G.C.M. Beaufort-Krol et al.
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Figure 1 Examples of representative electrocardiograms (leads I, AVF, V1, and V6) demonstrating the premature ventricular contraction
morphology to illustrate the specific type of ventricular ectopy. (A) Premature ventricular contraction with left bundle branch block inferior
axis; (B) premature ventricular contraction with left bundle branch block superior axis; and (C ) premature ventricular contraction with right
bundle branch block.
Exercise test
Discussion
All children had a normal exercise performance. Rise in
heart rate during exercise was normal. Premature ventricular contractions were suppressed by exercise in most
patients. In eight children, the PVCs did not disappear but
decreased in percentage at the highest heart rates. In all
children, PVCs disappeared at about the same heart rate
as during the Holter recording. Ventricular tachycardias
during exercise were not found. Exercise tests at last
follow-up (5.2 + 3.9 years; n ¼ 24) showed a normal
maximal exercise capacity (97 + 14% of the normal value
for age and length).10
Our study showed that indeed the percentage of PVCs in
children with a structurally normal heart decreases spontaneously with age. However, if the origin of the premature
beats is taken into account, this is only true for premature
beats originating from the LV (PVC-RBBB). The percentage
of premature beats originating from the RV (PVC-LBBB) did
not change over time. This is a new finding with consequences for the follow-up of these children. Like others
we found that PVCs in children with a structurally normal
heart were well tolerated, without morbidity or mortality.
All children had a normal LV function and exercise capacity
PVCs in children with normal hearts
1001
Figure 3 Percentage (mean + SD) premature ventricular contraction with right bundle branch block of total number of QRS complexes per
24 h in the Holter recording per age group. *P , 0.02; #P , 0.01.
at last follow-up. None of the children needed pharmacological treatment during follow-up.
Are there reasons to follow these children? There are indications from studies in adults with structurally normal
hearts that frequent premature ventricular beats may influence LV function. Facchini et al.7 found a subclinical but significant increase of LV dimensions in patients with frequent
PVCs compared with the control group. A recent study of
Bogun et al.11 found a decreased LV ejection fraction in
37% of the patients with frequent premature beats, which
normalized after radiofrequency ablation of the premature
beats. In both studies, the majority of the premature
beats originated from the RV. We do not know the response
of the PVCs to exercise in these patients, and it is not known
whether the PVCs were already present in the childhood or
developed later in the adulthood.
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Figure 2 Percentage (mean + SD) premature ventricular contraction with left bundle branch block of total number of QRS complexes per
24 h in the Holter recording per age group.
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G.C.M. Beaufort-Krol et al.
Figure 4 Heart rate (mean + SD) in the Holter recording at which premature ventricular contractions disappeared. *P , 0.01; #P , 0.06.
Limitations of the study
To study the natural history it was necessary to analyse the
data in different age groups, which unfortunately resulted in
small numbers of children in some age group. To determine
the natural history of PVCs, a much longer follow-up, in
which the data are collected prospectively, would have
been desirable.
Conclusion
We conclude that the natural history of PVCs in children with
an anatomically normal heart differs depending on the origin
of the PVCs. Premature ventricular contractions originating
from the LV disappear during childhood. Follow-up of these
children seems not necessary. In contrast, PVCs from the
RV do not disappear. Left ventricular dysfunction found in
adults with frequent PVCs may be an argument to continue
to follow these children, as well as the potential, but
small risk of developing ARVC. We advise that follow-up of
children consists of Holter recording, echocardiogram, and
exercise testing.
Conflict of interest: none declared.
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Moreover, in adults with frequent premature beats from
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Knowing that PVCs from the LV nearly disappear during
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the echocardiogram and if the PVCs disappear with exercise.
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