It can be normal, leftward (left axis deviation, or LAD), rightward (right axis deviation, or RAD) or indeterminate (northwest axis). The QRS axis is the most important to determine. However ...

6,11 Heart rates ≥30 beats/min are considered normal in highly trained athletes. Sinus arrhythmia is also common, particularly in younger athletes. IRBBB (commonly characterised as an rSR′ pattern in ...

In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).

However, in this scenario the axis could fall between 0 and -30, which is technically a normal QRS axis. To further distinguish normal from left axis deviation in this setting, look at lead II.

The rhythm is regular, at a rate of 150 beats/min. The QRS complex duration is normal (0.08 sec) with normal morphology. The axis is normal between 0° and +90° (positive QRS complex in leads I ...

Normal ECGs include common, training-related findings in athletes such as high QRS amplitude meeting voltage criteria for ... pathological Q-waves, left axis deviation and conduction delays and ...