Hemodynamic alterations in dogs with shock induced by intravenous injection of heartworm extract.

摘要: To elucidate one way of the shock mechanisms, hemodynamic alterations were examined in 7 dogs with heartworm (HW) extract-induced shock. The first alteration observed after injection HW extract was a decrease right ventricular end-diastolic pressure (RVEDP). After that, left (LV) pressure, LV systolic and dp/dt fell significantly, followed by cardiac output all to below detectable level (1.00 l/min). Since RVEDP depends on blood flow into ventricle, means reduction venous return. Therefore, this study showed that trigger is