The Nature of Fibrillary Contraction of the Heart. -its Relation to Tissue Mass and Form1 by Walter E. Garrey

I T is a noteworthy fact that the hearts (ventricles) of large animals fibrillate with great ease and only rarely recover from the fibrillary state, while small hearts rarely fail to recover. It was noted by McWilliam 2 that “spontaneous recovery may take place readily in the hearts of the cat, rabbit, rat, mouse, hedgehog, and fowl.” The ventricles of dogs do not usually recover spontaneously from fibrillation, although they do so in rare instances, as noted by Porter.3 The larger beef heart is one which enters into the fibrillary state with greatest ease and caprice. Erlanger 4 records this fact and states “that it is not often that fibrillation of the calves’ heart can be stopped, as in other hearts, by means of temporary perfusion with potassium chloride solution.” In this connection we may also refer to the well-known fact that fibrillation of the thin walled auricles is usually of a transitory nature, while that of the thicker ventricles of the same heart is much more prone to persist. It would appear obvious, from a consideration of these facts, that the size of the tissue masses involved in the process may have an important bearing on the induction of and recovery from the fibrillary state, yet, so far as we have been able to ascertain, these phenomena have never been systematically investigated from this viewpoint,