Safety and Effectiveness Outcomes of a Novel Sterile Titanium Clip Device-based Heart Valve Surgery in a Preclinical Disease Model

Background: Valvular heart disease (VHD) is a major subtype of life-threatening myocardial disease with high mortality, and in particular, among inpatients with degenerative valve diseases. There is an urgent need for the evaluation of the operability, effectiveness and safety of the novel sterile titanium clip device-based valve surgery with minimal level of invasion for VHD administration via preclinical studies. Methods: 18 small fat-tail sheep were prepared with extracorporeal circulation and performed upon thoracotomy and mitral valve shaping ring implantation. A total of 12 needles were conducted for mitral annulus suture, including 6 needles by utilizing the novel sterile titanium clip device (denoted as the experimental group) and another 6 needles by manual knotting (denoted as the control group), and the self-comparison was made at the indicated timepoints after surgery (30-day, 60-day, 90-day, 180-day). Along with recording the knotting time, echocardiography and blood tests were performed, with samples collected at the aforementioned timepoints. Pathological examination of the heart and vital organs was conducted to evaluate the safety and effectiveness of the implanted device. Results: Of the 18 sheep, 16 survived the operation for past-operation experimental data collection, including 3 at day 30, 3 at day 60, 4 at day 90, and 6 at day 180, respectively. Compared to the control group, the operation time was significantly reduced with clip implantation (P<0.01). The mitral valve forming ring was fixed firmly without disengagement or displacement, endothelializations were successful, with no peri-valvular leakage or marked thrombosis observed. The rate of thrombosis caused by thread ends in the experimental group was significantly higher than that in the control group at day 90, whereas no significant difference at day 180. Notably, with exception of two cases with visceral complications such as diffuse renal infarction caused by thromboembolism and small focal renal infarction, no significant differences in inflammatory response and other tissue responses or embolisms were observed in other organs. Conclusions: The novel aseptic clip device is much simpler and more convenient for significantly shortening the knot tying time during the flap annular implantation process, which demonstrated overall effectiveness and safety compare to manual knot tying.