OptiVol for Volume Assessment in Patients With Continuous Flow Left Ventricular Assist Device

OptiVol (Medtronic PLC, Minneapolis, MN) is a diagnostic feature of some cardiac implantable electronic devices (CIEDs) based on changes in thoracic impedance (TI) over time. Changes in TI can predict heart failure (HF) hospitalizations and mortality in HF populations. However, the utility of this feature is unknown in patients with a left ventricular assist device (LVAD). To determine if OptiVol and TI correlate with clinical HF events in a population of LVAD patients, hospitalization outcomes were collected retrospectively from the electronic health records at a single academic medical center in 80 LVAD patients with an OptiVol-capable CIED. Demographics, medical history, and available clinical data were reviewed and reported. The primary outcomes of interest were TI and OptiVol trends before and after hospitalization, and association of trends before and after these events was evaluated. Most patients had a HeartMate II LVAD and most CIEDs were defibrillators, and 23 (29%) had at least one HF hospitalization during the study period. HF hospitalizations were preceded by signs of volume overload in Optivol (60%) and TI (78%) with recovery of these measures post hospitalization in 33% and 25% of patients, respectively. Monitoring of TI and OptiVol may be one effective component of HF management in LVAD patients as part of a comprehensive program.