ABSTRACT
The EVAHEART 1 left ventricular assist device was miniaturized to the EVAHEART 2, with a new inflow cannula designed to mitigate the risks of malposition. To evaluate the safety of the new double-cuff tipless inflow cannula, in vivo studies were performed in healthy bovines. Eight consecutive studies were done: five short-term studies of hematological adaptation and three long-term studies of tissue adaptation. Each inflow cannula was purposefully implanted in the worst-case setting with marked malposition. Two studies terminated early: one because of an animal-specific ancillary component and one because of an accidental radial fracture. Six studies reached the study endpoint without major adverse events. One animal could not achieve proper anticoagulation because of warfarin resistance. Pump speed and power were maintained within stable, normal ranges. There were no major organ dysfunction or suction events. Necropsy results showed two cases of pannus formation around the inflow ostium because of warfarin resistance and hyperinflammation at the inflow cuff suture line. There was one case of trivial pannus; four cases were pannus-free, with no evidence of ventricular wall suction. No wedge thrombus formation occurred. The EVAHEART 2 tipless inflow cannula may reduce adverse events attributable to the inflow cannula, such as stroke.
Subject(s)
Heart-Assist Devices , Animals , Cattle , Equipment Design , Female , Male , Models, AnimalABSTRACT
BACKGROUND: In Japan, ventricular assist devices (VADs) have been used for patients with severe heart failure as a bridge to transplantation (BTT) since 1992. However, it was not until 1997, when the Organ Transplant Law was enacted, that medical devices received approval by the national health insurance system for that use. To encourage research and development of innovative medical devices, the Pharmaceuticals and Medical Devices Agency has established a public-private partnership in collaboration with academic societies, hospitals and manufacturers. METHODS: The Japanese registry for Mechanically Assisted Circulatory Support (J-MACS) is a prospective registry designed to be harmonized with the Interagency Registry of Mechanically Assisted Circulatory Support (INTERMACS). Participation in J-MACS is mandatory for device manufacturers to meet the conditions of approval as well as for hospitals to obtain authorization for reimbursement from the national health insurance system. RESULTS: From June 2010 to April 2015, 476 patients were registered at 31 hospitals. Of these, analysis of primary VAD patients (n = 332) revealed that their overall 360-day survival was 91% (implantable 93%, extracorporeal 84%). CONCLUSIONS: This initial report from J-MACS focuses on patients' demographics, device types, survival, competing outcomes, adverse events and successful examples of system failure detection.
