Physical mechanism of inhomogeneous left ventricular echocontrast

Streaky contrast and cyclic variations are often seen in video images of hearts during ultrasonic examinations when using intravenous injection of a transpulmonary ultrasound contrast agent. Several suggestions have been made in the literature to explain these phenomena, e.g. destruction of contrast agent by blood pressure variations between systole and diastole or blood jets emerging from small veins in the myocard (Thebesian veins) into the heart cavity. However, the results of this study demonstrate that inhomogeneous contrast and cyclic variations bath mainly depend on the acoustical intensity (I_max) and on flow conditions inside the heart