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According to available data the incidence of ventricular
tachyarrhythmias (VVTA) in subjects practicing sports is as yet not well defined. Moreover VVTA value can vary
within a large range: at one end they show a paraphysiologic, benign meaning, while in some cases they
underlie a structural cardiac disease, which, in turn, can preclude any sports practice.
While the casual appearence of VVTA on resting ECG in high level athletes is rare, in setting the baseline clinical
evaluation for legal admission to agonistic sport activity this finding is detected in about 25-35% of subjects1.
Even if epidemiological data offer a wide variability as regards VVTA incidence and prevalence, due to several
factors, such as the age difference, the groups selection, and the source of information (hospital, regional
committees, Institute of Sport Science – CONI), it can be approximately estimated that, among subjects practicing
agonistic sports, simple uncomplicated premature ventricular beats are present in 15-50%2 of cases, complex
premature ventricular beats in 1-10%1 of subjects, while figures concerning major arrhythmias (unsustained and
sustained ventricular tachycardias) are more difficult to exstract.
These epidemiological data are mostly obtained from studies on athletes based on Holter recordings (policentric
SIC sport study1). From them no significant difference was found between aerobic, anaerobic and mixed sports
performers3,4. Few authors have reported a higher prevalence of complex premature ventricular beats in
athletes in comparison with sedentary individuals, suggesting a proarrhythmic effect brought about by a training
– induced lengthening of electric systole5.
The pathophysiological mechanisms underlying VVTA in athletes can be caused by either sports-related
situations or intrinsic, concealed pathological substrates.
Among the former one can quote serum electrolytes alterations, the remarkable thickening of left ventricular
walls, cardiac cavities dilation, an unfavorable resetting of simpato – vagal balance and even the abuse of
stimulating drugs.
Concealed cardiac abnormalities which can represent the anatomic substrate of VVTA are fairly different in age
groups: in young subjects the most likely are anomalous origin development of coronary vessels, hypertrophic
cardiomyopathy, right ventricular arrhythmogenic cardiomyopathy, myocarditis (at every stage; active, in
regression, healed), mitral valve prolapse, isolated anomalies of conduction tissue, long QT syndrome, congenital
or acquired vascular diseases6-9. In middle-aged and older subjects, and any way in those aged more than 35-40
years, the prevailing anatomic pathological substrate of any VVTA is ischemic heart disease, both silent and
symptomatic.
Consequentely, the type and the depth of any diagnostic focusing on VVTA in subjects practicing sports change
according to their age group. In the middle-aged and older cohorts a VVTA needs to be studied by Holter
recording, echocardiography, and exercise stress testing; thereafter, in selected cases, a stress-echo or a
myocardial perfusional radionuclide examination may be advisable10. Among lab tests, thyroid hormones,
rheumatic activity and serum electrolytes determinations can be usefully added to routine samples. The
so-called third level arrhythmological evaluations, which comprise of signal-averaged ECG, head-up tilt testing,
transesophageal electric stimulation both at baseline and during exercise, and invasive electrophysiological
study, are the most advanced techniques for defining both arrhythmias features and risk patterns in VVTA.
In case of simple uncomplicated premature ventricular beats, if they are monomorphic, sporadic, without short
coupling intervals and not effort-related, and if they are detected in asymptomatic subjects, the prognostic value
is favourable and the go-ahead for agonistic sport activity can be given even in middle-aged or older subjects.
This finding, however, should be kept in consideration at subsequent examinations by the sport’s cardiologist
and sport medicine specialist.
In case of idiopathic ventricular tachycardia with typical monomorphology, having excluded any underlying
cardiac structural disease, it is recommended to apply a close follow-up, and to support the eventual temporary
permission for sport practice with third-level arrhythmological techniques.
In the period 1990-98, at our Center of Sport Medicine, among 3600 subjects aged more than 40 who were
submitted to clinical examination in order to have permission for agonistic sport activity, VVTA were found in
166 subjects, as follows:
1. in 127 subjects: simple uncomplicated premature ventricular beats;
2. in 36 subjects: complex premature ventricular beats (Lown II);
3. in 2 subjects: idiopathic ventricular tachycardia with RBBB morphology;
4. in 1 subject: idiopathic ventricular tachycardia with LBBB morphology.
All subjects in the first group were made idoneous to practice sports and checked in time with an average
follow-up of 3 years: only in one case at the last examination a silent ischemic heart disease was diagnosed.
Individuals in the second group were submitted to second- and third-level investigations, which identified a
mitral valve prolapse with mild valvular rigurgitation in two cases, and an asymmetric hypertrophic cardiopathy,
secondary to sistemic hypertension, in another case. None of the three patients showed any unfavourable
evolution and were given limited permission to practice sport, according to tab. A of COCIS Protocol11,12. A
further patient in group 2 was submitted to a myocardial perfusion radionuclide testing showing effort ischemia,
and to a coronary angiography, which identified an isolated stenosis in the left anterior descending coronary
artery, treated with percutaneous angioplasty. Finally it seems worth noting that 12 subjects belongings to this
group showed a reduction in their VVTA score (i.e. lowering in Lown class), up to a total disappearence of VVTA
at the ECG, Holter, and ergometric test performed in the following years.
Out of the three subjects showing idiopathic ventricular tachycardia, one was submitted to a successful
transcatheter radiofrequency ablation of arrhythmic substrate, another was effectively treated with verapamile.
In conclusion our results, together with available literature data, confirm that the observation of premature
ventricular beats in subjects practicing sport seem to be casual, aspecific and of low prognostic value, although
in our cases the short follow-up does not allow any definitive prognostic labelling. Furthermore, in such clincal
settings, the use of the second- and third-level diagnostic evaluation appears essential, above all in middle-age
subjects.
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