Evaluation of a Ventricular Assist Device System

Abstract

Inadequate research exists regarding testing of a ventricular assist device (VAD) for susceptibility to radiation damage. Specifically, minimal data are available to radiation oncologists prescribing treatment plans for patients with an implanted VAD. As the number of implanted devices increases, patients requiring radiation at tissue sites near or at the device will increase. The purpose of this study is to provide the first analysis of radiation effects of proton beams on VADs. Five left VAD (LVAD) pumps (HeartWare Inc., Miami Lakes, FL) were exposed to proton beam radiation at a calibrated dose rate of 5 Gy/min up to a cumulative dose of 70 Gy. The Heartware LVAD pump recorded parameters including power (W), speed (revolutions/min), and estimated flow (L/min). Analysis of collected data after each irradiation found no deviation in pump parameters from baseline values. The Heartware LVAD pump exhibited no change in device function when directly irradiated by a high energy proton beam. Secondary neutron fluence created in the proton beam during irradiation had no effect on external components including the system controller and batteries powering the Heartware LVAD.

In Vitro PET Imaging of a Miniature Ventricular Assist Device

“…The secondary findings of this study regard image quality and retention of radiotracers inside the pump. Our previous testing of x-ray and proton radiation therapies on the HVAD pump (a pump that is currently commercially available from HeartWare Ò , Inc.) showed scattering and attenuation on the images (16,17). PET imaging in the current study clearly showed the inflow and outflow regions of the pump; only the portion of the pump with the spinning impeller was obscured (Fig.…”

Safe delivery of lung stereotactic body radiation therapy in a patient with a left ventricular assist device and implantable cardioverter defibrillator

“…The impeller contains multiple large rare earth motor magnets, which are driven by electromagnetic force. This device further has an external microprocessor‐based controller, connected to the internal pump via a percutaneous driveline, which operates the pump, manages power sources, monitors pump function, provides diagnostic information, and stores pump parameter data …”

“…They further suggested that computer modeling underestimates the pretreatment dose in patients when the device is in the radiation field . Similarly, no change in HVAD function (n = 5) was found in response to proton beam therapy up to 70 GyE . No case reports of photon radiation in the specific setting of a third‐generation LVAD exist, although 4 case reports of safe treatment with radiation in earlier generation LVADs are available …”

“…Yet, no large clinical studies have been done to establish the safety or dose constraints of radiation in these cardiac devices. The evidence regarding radiation in an LVAD‐dependent patient is limited to case reports and in vitro studies . Here, we report the first case of thoracic stereotactic body radiation therapy (SBRT) to the left lower lobe of the lung for a suspected solitary lung carcinoma in a patient with a third generation LVAD (Heartware ® ) and ICD.…”

“…The evidence regarding radiation in an LVAD-dependent patient is limited to case reports and in vitro studies. [5][6][7][8][9][10] Here, we report the first case of thoracic stereotactic body radiation therapy (SBRT) to the left lower lobe of the lung for a suspected solitary lung carcinoma in a patient with a third generation LVAD (Heartware ® ) and ICD. This report illustrates that this treatment approach can be safely and successfully used to manage this complex patient population.…”