When I did my medical for my PPL aged 60 the ECG picked up an anomaly. The guys reaction was "I've never seen one like that before!" Anyway I was sent to a cardiologist and had the lot, echocardiogram etc and he found nothing. In the end the chap just said "it's just a funny ECG -it happens"
Anyway, passed my medical, and my heart is still ticking away ok 9 years later