At an Inventors weekend at Whiteley Shopping Outlet in Farnham
2-3/8/2003, this trace was carried out on a 79 year old man with a pacemaker

I showed him this trace of another man with a pacemaker

He decided to go and have his pacemaker looked at
and the battery was found to be flat

Invented / Developed / Designed /Manufactured by Mr Robert Merlyn Farwell 
PIElectronics (Pioneering Inventions & Electronics)
Camalot Castle Parkfield Road Stourbridge DY8 1HD. UK