Phonocardiogram (PCG) signal processing systems and methods for determining cardiac tissue and valvular blood flow parameters

A method for computing proxy metrics for echocardiographic parameters, the method comprising:

• (a) receiving PCG acoustic signals from one or more sensors attached to a subject;
• (b) receiving simultaneously electrocardiogram (ECG) signals from one or more sensors attached to the subject;
• (c) processing the denoised PCG signals into one or more of temporal features, amplitude features, frequency features, or spectral entropy features for each heartbeat of the same subject;
• (d) converting the extracted features into a plurality of cardiac tissue and valvular blood flow parameter analogues (proxy metrics) based on a set of predetermined conversion equations, said conversions comprising;
• (i) processing the amplitude features for all heartbeats of the same subject into a proxy metric for the peak velocity of blood flow through the subject's mitral valve during early diastole (peak E velocity);
• (ii) processing the frequency features for all heartbeats of the same subject into proxy metrics for the average flow velocity through the subject's mitral valve during early diastole (e′ velocity) and the maximum volume of the subject's left atrium indexed to the subject's body surface area (LAVi);
• and
• (iii) processing the spectral entropy features for all heartbeats of the same subject into a proxy metric for the ratio of early-to-late peak flow velocities through the subject's mitral valve during diastole (E/A ratio) and the peak velocity of blood backflow through the subject's tricuspid valve during systole (peak TR velocity).