The making of The Heart Cycle commenced in 1973 with a 'live' real-time, closed-circuit television (CCTV) solo, private performance, recorded to videotape. Live in the sense of performed iterations, proceeding toward the work's final completed duration, determined by the running time of  a 1950s era, 16mm, biology, instructional film of the same title.

Reference: "The transforming moves and exploratory probes employed in performing the mediums, (film and analogue video), is reflected in the heuristic production of evidence in viewing the completed artwork; light as abstract movement, with synchronous/asynchronous sound, as image of place and surface, as image of presence and agency, interrogated within a continuous present." (Kacunko, Re:live Media Art Histories 2009 Refereed Conference ...)
exhibition: The work was selected for the Video Show 1975, serpentine Gallery, London. and REWIND, ‘Early British Video Art,DVD’ box set pub. 2009 Lux, London.University of Dundee Artists’ Video Archive.

See also a later iteration The Heart Cycle 2021