[Phenomenon of post-stress rigidity in the left ventricular myocardium].

The effect of emotional painful stress on myocardial distensibility and contractility was studied on an isolated papillary muscle of the rat left ventricle. The EPS resulted in decreased distensibility and depressed amplitude of papillary muscle contraction. These disturbances are suggested to play the main role in the development of heart insufficiency under stressful situations.