Pace the heartbeat by double-heartbeat-frequency sound wave

In our previous study, we developed a method to pace the heartbeat of rats externally by applying heartbeat-synchronizing mechanical stimulation. Meanwhile, the blood pressure also changed accordingly with the heart rate. The external sound wave may assist the blood distribution, and this phenomenon may provide a new direction for study of cardiovascular diseases, such as arrhythmia and hypertension. The kidneys occupy the largest portion of cardiac output, abnormalities of the renal arterial system are thought to be the main cause of hypertension. Since we found that the resonance frequency of renal vasculature is double that of heart rate, we now focused on the effects of a sound wave with double-heartbeat-frequency.