Authors: Guy Evans, Simon Laing / Codes: HAP5 / Published: 13/05/2015
Athletes in the ED, my ED, we hardly ever see them..or so you might think. Actually the definition of an athlete means you come across them far more often than you may first have thought.
Sudden cardiac death (SCD) is the leading cause of death in athletes during sport. Whether obtained for screening or diagnostic purposes, an ECG increases the ability to detect underlying cardiovascular conditions that may increase the risk for SCD.
As with most patients in the ED, ECGs are often obtained in athletes and can look quite abnormal due to the cardiac hypertrophy and increased vagal tone that occurs with regular physical training. It is important that we, as clinicians are able to decipher between normal changes associated with regular physical activity and those that may represent underlying cardiovascular pathology. By identifying these normal changes on an athletes ECG we can reduce the anxiety associated with onwards specialist cardiology referral.
An athlete is defined as an individual who engages in regular exercise or training for sport or general physical fitness, typically with a goal of improving performance. As you can see, this is quite a large cohort of patients attending the ED. To think of the definition of an athlete more quantitatively, we can define an athlete as someone who engages in >4 hours intensive physical activity a week.
Rather helpfully in 2012, a consensus statement was published outlining criteria that can be deemed as normal on an athletic ECG. If any of these criteria are identified, in the absence of symptoms, the clinician can be reassured that the changes are due to an athletic heart rather than cardiac pathology. These criteria were named the Seattle criteria after the venue at which the consensus statement took place. The criteria can be applied to asymptomatic athletes between the ages of 14-35 years old.
The criteria are extremely useful and are outlined below:
- Sinus bradycardia ( 30 bpm)
- Sinus arrhythmia
- Ectopic atrial rhythm
- Junctional escape rhythm
- 1 AV block (PR interval > 200 ms)
- Mobitz Type I (Wenckebach) 2 AV block
- Incomplete RBBB
- Isolated QRS voltage criteria for LVH
- Except: QRS voltage criteria for LVH occurring with any non-voltage criteria for LVH such as left atrial enlargement, left axis deviation, ST segment depression, T-wave inversion or pathological Q waves
- Early repolarisation (ST elevation, J-point elevation, J-waves or terminal QRS slurring)
- Convex (domed) ST segment elevation combined with T-wave inversion in leads V1V4 in black/African athletes
Table 1: Normal ECG findings in athletes
The criteria do have limitations however. ECGs alone cannot always identify underlying cardiac pathology and further investigation may be required especially if the athlete has cardiac sounding symptoms, or strong family history for cardiac disease. In these circumstances expert cardiology input is recommended.
The Seattle Criteria published paper also outlines a list of ECG findings in athletes that are suggestive of underlying cardiac pathology. These are outlined below:
|T-wave inversion||>1 mm in depth in two or more leads V2V6, II and aVF, or I and aVL (excludes III, aVR and V1)|
|ST segment depression||0.5 mm in depth in two or more leads|
|Pathologic Q waves||>3 mm in depth or >40 ms in duration in two or more leads (except for III and aVR)|
|Complete left bundle branch block||QRS 120 ms, predominantly negative QRS complex in lead V1 (QS or rS), and upright monophasic R wave in leads I and V6|
|Intraventricular conduction delay||Any QRS duration 140 ms|
|Left axis deviation||30 to 90|
|Left atrial enlargement||Prolonged P wave duration of >120 ms in leads I or II with negative portion of the P wave 1 mm in depth and 40 ms in duration in lead V1|
|Right ventricular hypertrophy pattern||RV1+SV5>10.5 mm AND right axis deviation >120|
|Ventricular pre-excitation||PR interval <120 ms with a delta wave (slurred upstroke in the QRS complex) and wide QRS(>120 ms)|
|Long QT interval*||QTc470 ms (male)QTc480 ms (female)QTc500 ms (marked QT prolongation)|
|Short QT interval*||QTc320 ms|
|Brugada-like ECG pattern||High take-off and downsloping ST segment elevation followed by a negative T wave in 2 leads in V1V3|
|Profound sinus bradycardia||<30 BPM or sinus pauses 3 s|
|Atrial tachyarrhythmias||Supraventricular tachycardia, atrial-fibrillation, atrial-flutter|
|Premature ventricular contractions||2 PVCs per 10 s tracing|
|Ventricular arrhythmias||Couplets, triplets and non-sustained ventricular tachycardia|
Table 2: ECG findings considered to be unrelated to regular training or expected physiological adaptation to exercise. These may suggest the presence of pathological cardiovascular disease, and require further diagnostic evaluation.
Further investigation is required if any of the findings in table 2 are present on the ECG.
In essence, the Seattle Criteria provide a useful tool in assessing ECGs in the athletic population and can serve to reduce the need for onward referral to specialist cardiology services and thus reduce the anxiety associated with further evaluation. The criteria are not to be used in symptomatic individuals and should be used in athletes between the ages of 14-35yrs old. Further evaluation is required if cardiac sounding symptoms are present or if there is a strong family history of cardiac pathology.
If you are interested in learning more about the interpretation of ECGs in athletes, you may find the FREE online learning modules helpful which can be found on the BMJ website at: http://learning.bmj.com/learning/course-intro/.html?courseId=10042239
I hope armed with this information you will find the approach to the athletes ECG a little easier. If you have any feedback or comments please post them below or contact me directly via my twitter handle @drguyevans.
Thanks for listening!
- Corrado D, Pelliccia A, Heidbuchel H, et al. Recommendations for interpretation of 12-lead electrocardiogram in the athlete. Eur Heart J 2010;31:24359
- Uberoi A, Stein R, Perez MV, et al. Interpretation of the electrocardiogram of young athletes. Circulation 2011;124:74657
- Drenzner J, Ackerman M, Anderson J, et al. Electrocardiographic interpretation in athletes: the Seattle Criteria. Br J Sports Med 2013;47:122-124