I am a college professor in exercise physiology. The attached ECG was obtained during a submax treadmill test on a student (rest & recovery shown). Can someone please ‘interpret’ this for me – specifically what appears to be a second S-wave seen in aVF and II (in rest & recovery) and aVL (in recovery).
Also why did QRS switches from mostly positive to mostly negative in aVL?
These two things appeared “abnormal” to me so I searched the internet for an explanation but had no luck.
Note: the subject had a hairy chest and towards the end of the test electrode VI was not sticking very well so he held it in place.
My sincere thanks for your help!!