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Published on: February 28, 2012
In vivo Hemodynamic Evaluation of an Implantable Left Ventricular Assist Device in a Long-term Anti-coagulation
Insights
This study shows the CH-VAD™ left ventricular assist device (LVAD) is well tolerated in calves. An effective anticoagulation regimen using warfarin prevented thrombosis and hemolysis, paving the way for future studies.
Area of Science:
- Cardiovascular Engineering
- Biomedical Devices
- Hematology
Background:
- Severe heart failure necessitates advanced treatments like left ventricular assist devices (LVADs).
- Thrombosis and bleeding are critical complications requiring optimized anticoagulation.
- The CH-VAD™ offers superior hemocompatibility due to its magnetically levitated rotor design.
Purpose of the Study:
- To evaluate the hemocompatibility of the CH-VAD™ in a bovine model.
- To establish a safe and effective anticoagulation regimen for CH-VAD™ implantation.
- To prepare for future Good Laboratory Practice (GLP) studies.
Main Methods:
- Implantation of the CH-VAD™ in two calves.
- Perioperative heparin infusion followed by oral warfarin for anticoagulation (target INR 2.0-3.0).
- Monitoring of pump performance, animal health, hematology, and thrombus formation over approximately 60 days.
Main Results:
- The CH-VAD™ demonstrated good hemocompatibility in the bovine model.
- The anticoagulation regimen effectively prevented significant thrombus and thromboembolic lesions.
- Low plasma free hemoglobin levels indicated minimal hemolysis.
Conclusions:
- The CH-VAD™ is well-tolerated in a bovine model with the established anticoagulation protocol.
- This study provides a foundation for future GLP investigations of the CH-VAD™.
- The findings support the potential of the CH-VAD™ for treating advanced heart failure.
Abstract:
Left ventricular assist devices (LVADs) are used to treat patients with severe (New York Heart Association class IV) heart failure. Thrombosis and bleeding are severe LVAD-related complications; thus, an effective anticoagulation regimen is crucial for successful postoperative management. The CH-VAD™ (CH Biomedical, Inc.) is a small, implantable, full-support (>5 L/min) LVAD with a centrifugal flow pump that has a fully magnetically levitated rotor, which confers superior hemocompatibility. In this study, the CH-VAD™ was implanted in two calves to evaluate its hemocompatibility and to establish an anticoagulation regimen for future GLP (good laboratory practice) studies. Heparin infusion was used during the surgery, and during postoperative management, the proper dosage of warfarin was given orally to maintain an international normalized ratio (INR) between 2.0 and 3.0. Pump performance, animal condition, and hematology results were recorded throughout the study (approximately 60 days). The results show that under the established anticoagulation regimen, the CH-VAD™ was well tolerated in the bovine model, with no significant thrombus or thromboembolic lesion formation in distal end organs. Low plasma free hemoglobin levels suggest that the device did not cause hemolysis. These results and the experience gained pave the way for future GLP studies.
