Continuous-flow left ventricular assist devices (CF-LVADs) are miniaturised devices implanted in end-stage heart failure patients to support the failing left ventricle. CF-LVADs alter the blood flow in the cardiovascular system, causing further complications. Additional health disorders during CF-LVAD support may increase morbidity and mortality in patients. Therefore, continuously monitoring blood flow through CF-LVADs may help to detect the complications early, allowing for timely interventions and reducing mortality in patients implanted with CF-LVADs. The lack of long-term reliable and implantable sensors in CF-LVADs does not allow for the real-time continuous monitoring of haemodynamic signals in the cardiovascular system.

In this study, intrinsic CF-LVAD electrical current signals were continuously monitored and analysed to evaluate cardiac function and detect cardiovascular disorders. CF-LVAD electrical current signal waveforms over a 600 s period in patient-specific RR intervals were analysed to detect normal sinus rhythm, Atrial Fibrillation (AF) with unimodal and bimodal RR interval distributions, and right ventricular failure during CF-LVAD support.

The average RR interval duration in sinus rhythm was 0.828±0.051 s and the coefficient of variation was 0.006. The average RR interval duration in AF with unimodal distribution was 0.512±0.106 s and the coefficient of variation was 0.207, whereas the mean of the RR intervals in AF with a bimodal distribution was 0.884±0.260 s and the coefficient of variation was 0.294. The CF-LVAD electrical current signal waveform was altered because of right ventricular failure and AF with both unimodal and bimodal cardiac RR interval distributions. The amplitude of the CF-LVAD electrical current signal was relatively small because of right ventricular failure and AF with bimodal cardiac RR interval distribution, which caused the amplitude to vary over each cardiac cycle.

Cardiovascular disorders can be detected by monitoring and analysing the features of CF-LVAD electrical current signals in patients supported with CF-LVADs.