title: Implantable physiologic controller for left ventricular assist devices with telemetry capability.
abstract: OBJECTIVE
  Rotary type left ventricular assist devices have mitigated the problem of durability associated with earlier pulsatile pumps and demonstrated improved survival. However, the compromise is the loss of pulsatility due to continuous flow and retained percutaneous driveline leading to increased mortality and morbidity. Lack of pulsatility is implicated in increased gastrointestinal bleeding, aortic incompetence, and diastolic hypertension. We present a novel, wirelessly powered, ultra-compact, implantable physiologic controller capable of running a left ventricular assist device in a pulsatile mode with wireless power delivery.
  
  
  METHODS
  The schematic of our system was laid out on a circuit board to wirelessly receive power and run a left ventricular assist device with required safety and backup measures. We have embedded an antenna and wireless network for telemetry. Multiple signal processing steps and controlling algorithm were incorporated. The controller was tested in in vitro and in vivo experiments.
  
  
  RESULTS
  The controller drove left ventricular assist devices continuously for 2 weeks in an in vitro setup and in vivo without any failure. Our controller is more power efficient than the current Food and Drug Administration-approved left ventricular assist device controllers. When used with electrocardiography synchronization, the controller allowed on-demand customization of operation with instantaneous flow and revolutions per minute changes, resulting in a pulsatile flow with adjustable pulse pressure.
  
  
  CONCLUSIONS
  Our test results prove the system to be remarkably safe, accurate, and efficient. The unique combination of wireless powering and small footprint makes this system an ideal totally implantable physiologic left ventricular assist device system.
authors.affiliation: Bonde Artificial Heart Laboratory, Department of Surgery, Yale School of Medicine, New Haven, Conn.
authors.forename: Siavash S
authors.initials: SS
authors.lastname: Asgari
authors.affiliation: Bonde Artificial Heart Laboratory, Department of Surgery, Yale School of Medicine, New Haven, Conn. Electronic address: pramod.bonde@yale.edu.
authors.forename: Pramod
authors.initials: P
authors.lastname: Bonde
mesh_terms: D000465:Algorithms; D000818:Animals; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory / Q000295:instrumentation*; D015716:Electrocardiography, Ambulatory / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D006339:Heart Rate; D006353:Heart-Assist Devices; D008422:Materials Testing; D023421:Models, Animal; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D011673:Pulsatile Flow; D012815:Signal Processing, Computer-Assisted; D013552:Swine; D013686:Telemetry / Q000295:instrumentation*; D013997:Time Factors; D016277:Ventricular Function, Left; D059015:Wireless Technology / Q000295:instrumentation*
keywords: 27; ECG; EMF; FREE-D; Free-Range Resonant Electrical Energy Delivery; LVAD; MCL; UMC-Physio; difference between systolic and diastolic pump speeds; electrocardiography; electromotive force; left ventricular assist device; mock circulation loop; revolutions per minute; rpm; ultra-compact implantable physiologic controller; ΔRPM