Hyperdynamic circulation is abnormally increased circulatory volume. Systemic vasodilation and the associated decrease in peripheral vascular resistance results in decreased pulmonary capillary wedge pressure and decreased blood pressure, presenting usually with a collapsing pulse, but sometimes a bounding pulse. In effort to compensate the heart will increase cardiac output and heart rate, which accounts for the increased pulse pressure and sinus tachycardia.[1] The condition sometimes accompanies septic shock, preeclampsia, and other physiological and psychiatric conditions.__TOC__