Background: Degenerative mitral valve disease is the most common heart disease in dogs. Successful development of a percutaneous transcatheter mitral valve would have a dramatic effect on the treatment of this disease.Hypothesis/
Objective: We hypothesized that our valve could be deployed through a 9.5Fr catheter via the trans-jugular transseptal route without untoward effects on the heart.Animals: Two purpose-bred research dogs were used in this study.
Methods: The study was a case-series design. Valve delivery was performed through a 9.5Fr steerable sheath under fluoroscopic and transesophageal echocardiographic guidance. Deployment of three anchors in the LV apex preceded the valve assembly implantation in the mitral annulus. Echocardiographic evaluations of heart function and valve performance were performed post-implantation, and Days 1, 14, 30. Animals were euthanized at Day 30, and the hearts underwent histologic assessment.
Results: Successful deployment and anchoring of the valve in the mitral annulus was achieved in one dog. In the other, the anchoring system deployed successfully but there was malalignment of the valve assembly. Trace MR was observed in both dogs after implantation without LVOT obstruction or pericardial effusion. Follow-up echocardiograms indicated that the devices remained in the initial position, with mean transvalvular pressure gradient of 1mmHg and trace to mild MR. Normal LV function was maintained without LVOT obstruction (mean PG< 3mmHg) or pericardial effusion observed from Day 1 to Day 30.Conclusions and clinical importance: Transcatheter placement of the valves had no negative effects on the subjects, which will allow us to proceed to clinical trials.