Abstract
Right ventricular isometric systolic tension (IST) was measured with a strain gauge lever system prior to and 25-30 days following surgically induced tricupid insufficiency and pulmonary stenosis (TI and PS), each animal serving as its own control. IST was shown to be markedly reduced (53.7%) in heart failure dogs with TI and PS. This decrease in IST was accompanied by a 26.8% increment in heart rate and a decrease in the rate of myocardial relaxation. These and several other factors were discussed in relation to cardiac reserve and decompensation.
