Chronic in vivo studies have been conducted since 1990 with a completely implanted total artificial heart (TAH). The system requires no percutaneous conduits and is intended for use as an alternative to transplantation. It includes a dual pusherplate pump and rollerscrew actuator, implanted electronics and battery assembly, transcutaneous energy transmission system, 2-way wireless telemetry, and an intrathoracic compliance chamber. Accumulated test time in 53 animals exceeds 4.4 years, with 9 animals exceeding 12 weeks survival, and the longest surviving 23 weeks. The chronic studies are intended primarily to evaluate biological response, and secondarily to evaluate device performance and durability in actual use. Results show a low incidence of thromboembolism with modest anticoagulation, occurring in most cases secondary to abnormally low flow or sepsis. Sepsis occurs infrequently, except for studies using chronic indwelling catheters and in one case of perioperative contamination. Plasma hemoglobin typically returns to the normal range, indicating low hemolysis. Indicators of renal and hepatic function, including blood chemistry and histopathology, indicate normal end organ function. In terms of device performance, these studies demonstrate fully automatic control of cardiac output and left-right balance requiring no intervention, wireless energy transmission in everyday use, and stable function of a compliance chamber.
All Science Journal Classification (ASJC) codes
- Biomedical Engineering