Measures intracardiac pressure with non-invasive, high accuracy, and high time resolution. The pressure is calculated from the attenuation curve and resonance curve of the signal reflected from the ultrasound contrast agent. In addition, a multi-component droplet type contrast agent is injected into the body, the composition is set so that the pressure range to be detected becomes gas-liquid equilibrium, and the bubble diameter depends on the pressure, increasing the pressure to the attenuation curve and resonance curve. Reflect and realize highly accurate pressure measurement.非侵襲・高精度・高い時間分解能で心内圧を計測する。超音波造影剤から反射された信号の減衰曲線、共鳴曲線から圧力を計算する。また、多成分液滴型造影剤を体内に注入し、検出したい圧力範囲を気液平衡になるように組成を設定し、気泡径を圧力に依存させて、減衰曲線、共鳴曲線へ圧力を強く反映させ、高精度な圧力計測を実現する。
