[The sympathetic innervation of the myocardium and its damage in acute massive pulmonary embolism].

The state of the adrenergic heart innervation and injuries of right (RV) and left (LV) ventricles in experimental massive embolism of pulmonary arteries (MEPA) were studied in 62 dogs under conditions of the intact thorax and natural respiration. The degree of focal myocardial injuries depended upon the density of the sympathetic innervation: when the density of adrenergic nerves (AN) was high the number of injuries decreased. Hypercatecholaminemia developing at the early period of MEPA has a cardiotoxic effect, more pronounced in dogs with decompensation. A decrease of the AN density and increase of injuries in RV and LV were observed in long-term experiments. The results allow explaining the possibility of the adaptation processes breakdown by the development of heart failure in acute MEPA.