Wearable and portable system and method for measuring cardiac parameters for detecting cardiopathies

A method for measuring cardiac parameters, comprising:

• generating a seismocardiographic signal;
• generating an envelope signal correlated to the seismocardiographic signal;
• segmenting the envelope signal into signal segments having a repetitive pattern, the segmenting of the envelope signal includes
• generating a sequence of quantized samples having a first logic level in a case where the envelope signal exceeds a threshold and a second logic level in a case where the envelope signal is lower than the threshold,
• searching, within the sequence of quantized samples, maximum values of the envelope signal between a switching time of the quantized samples between the second and the first logic levels and a successive switching time from the first to the second logic level, and
• associating the switching time and the successive switching time with respective maximum values of the envelope signal forming clusters;
• identifying, among the signal segments, pairs of successive peaks such that a first peak of each pair of successive peaks is a systolic peak and a second peak of each pair of successive peaks is a diastolic peak;
• and
• calculating a systolic period and a diastolic period for each pair of successive peaks.

A device, comprising:

• a sensor configured to generate a seismocardiographic signal;
• and
• a processor configured to:
• generate an envelope signal of the seismocardiographic signal;
• segment the envelope signal into signal segments having a repetitive pattern, the processor, in the segmentation of the envelope signal, generates a sequence of quantized samples having a first logic level in a case where the envelope signal exceeds a threshold and a second logic level in a case where the envelope signal is lower than the threshold;
• determine pairs of successive peaks in the signal segments, respectively, each of the pairs of successive peaks including a first peak having the first logic level and a subsequent second peak having the first logic level;
• and
• determine a plurality of characteristics including a heart rate, a systolic period, and a diastolic period based on the pairs of successive peaks, the processor, in the determination of the plurality of characteristics,
• determines the systolic period based on a first time length between the first peak and the second peak in a first pair of the pairs of successive peaks;
• determines the diastolic period based on a second time length between the second peak in the first pair of the pairs of successive peaks and the first peak of a second pair of the pairs of successive peaks;
• and
• determines the heart rate based on a sum of the first time length and the second time length.