Artificial Pacemaking and Sinus Rhythm.

The patients reported form part of a larger series of 60 patients with Stokes-Adams disease treated with artificial pacemakers, which is being reported in full elsewhere. The series contained 32 men between the ages of 39 and 81, and 28 women between 27 and 76. There was a bias towards the older age-groups with 53 per cent of the men and 62 per cent of the women being over 65 years. No patients with heart block following cardiac surgery have been included in this series. Artificial pacing was achieved by means of an electrode catheter passed to the right ventricle from a peripheral vein, the heart being driven by a small adjustable pacemaker (Davies, 1962). Exercise studies were carried out on a bicycle ergometer, electrocardiograms were taken on a Cambridge photographic recorder, and cardiac output was measured by a dye dilution technique using Coomassie blue as described in a previous publication (Sowton, 1964a).