Enhanced piezoelectric sensor to distinguish real-time arrhythmia for predicting heart failure

Monitoring cardiac rhythm is crucial for diagnosis of heart failure. However, the deficient sensitivity of polyvinylidene fluoride (PVDF) sensors impede their application in monitoring of cardiac rhythm due to the limited piezoelectricity. Here, doping of CoFe₂O₄ and aligning fibers were jointly adopted to enhance the piezoelectricity of PVDF, attributed to the transformation of α-PVDF to β-PVDF from 51.54 to 82.36 % confirmed by FTIR and First Principles simulation. Then the higher sensitivity piezoelectric sensors were developed based on aligned PVDF/CoFe₂O₄ accompanying with the superior frequency characteristics, rapid response, endurance stability, permeability and self-cleaning capabilities, compared to that of random PVDF/CoFe₂O₄ and PVDF sensors, which were 17.28, 13.40 and 2.16 mV kPa ^-1, respectively. Thus, the sensitivity of PVDF/CoFe₂O₄ sensors was sufficient to distinguish the variations of cardiac rhythm or arrhythmia of the established and verified heart failure rat model, including amplitude, cycle and frequency. The notable characteristic of an evolving heart failure was the significantly decreased amplitude initially, followed by a dramatic drop in the cycles of cardiac impulse. Hence, this non-invasive method is promise in providing valuable warning signs for predicting heart failure based on aligned PVDF/CoFe₂O₄ sensors, as well as in the prevention its occurrence.