Peter Leslie was the first to record a His Bundle electrogram on 23/11/1972.

Two years later, on 6/11/1974, I undertook the first programmed electrical stimulation study, using a stimulator constructed by Don McCallum.  The stimulator produced pacing trains only.

My interest in electrophysiology dated from a lecture by Dr Dirk Durrer from Amsterdam on the topic of re-entry, given at the National Heart Hospital in London in 1968.   During a period of study-leave in 1975, I spent some time in Amsterdam observing electrophysiology studies, and returned to Wellington keen to put what I had learned into practice.

Don McCallum built a new stimulator for me, which delivered programmed single extrasystoles.