The Relationship Between R-Wave Magnitude and Ventricular Volume During Continuous Left Ventricular Assist Device Assistance: Experimental Study

The current use of left ventricular assist devices (LVADs) as destination therapy is associated with the clinical need of monitoring patient-pump interaction. To this aim, the present work investigated the possibility of getting useful information about the status of the assisted left ventricle using electrocardiographic (ECG) data. A total of six animals, undergoing Gyro Centrifugal Pump 2 implantation (a new version of Gyro Centrifugal Pump C1E3 [Kyocera Corporation, Kyoto, Japan]) and CircuLite Synergy Micropump (CircuLite, Inc., Saddlebrooke, NJ, USA) in atrio-aortic connection, were analyzed. Data refer to different LVAD speeds with consequently different levels of ventricular unloading. From ECG signal, the R wave peak was individuated together with the corresponding left ventricular volume. Then on both signals, a moving average analysis was performed to reduce the effect of the ventilation. A regression and correlation analysis performed on the two resulting signals evidenced that the R wave peak and the ventricular volume are strictly related. Specifically, any change of LVAD speed, inducing a change in ventricular volume, is associated with a change in R wave peak value. The present work is a first step in investigating the usefulness of the ECG signal during LVAD therapy, for the monitoring of mechanical parameters of the heart such as the ventricular volumes. The correlation found between the ECG and the ventricular volume can be a promising starting point for possible future noninvasive LVAD patient monitoring.