THE DYNAMIC CHANGES IN THE VENTRICLES FOLLOWING LIGATION OF THE RAMUS DESCENDENS ANTERIOR

Publisher Website
Google Scholar
Abstract
The changes in the ventricular beat following ligation of the isolated ramus descendens branch of the anterior coronary artery in the dog were studied by optically recording the pressure pulses from the ventricular cavities, aorta and pulmonary artery. Ligation was uniformly followed by typical hypodynamic beats, the systolic discharge being greatly reduced; systolic and diastolic pressures fell. These effects, however, were compensated for within 4-7 min. through an increase in diastolic size and a rise of initial tension. In approximately & of the experiments, systolic pressures in the aorta and ventricle were not decreased primarily, but the typical initial abbreviation of contraction was always present. The results indicated: (1) that the primary depression of contraction and decrease in ventricular systole are caused by deletion of fractionate contractions in potentially in-farcted areas; (2) that absence of the initial depression may be accounted for by primary anoxemia of some affected muscle fractions, but (3) that the real compensation by which the contractions are restored is due to the increase in diastolic size and initial tension.

This publication has 1 reference indexed in Scilit: