[Atrial systole. Study of its role in the normal subject and in left ventricular insufficiency]

In order to study the importance of atrial systole, the authors used different stimulus modalities at the same rate; they stimulated the right ventricle, the right atrium, and the two. The haemodynamic parameters were monitored by microcatheterisation of both right and left sides. A comparative study using controls and patients with left ventricular failure showed the improvement in the haemodynamic picture which was obtained in the latter group when the atrio-ventricular sequence was correct.