Preliminary study on local medical treatment of aortic valve calcification: Drug delivery to aortic valve in rat

Background Aortic valve stenosis （AVS） is the most common heart valve disease in elderly society. The effective treatment for AVS is surgical aortic valve replacement but with extremely invasive. Although transcatheter aortic valvereplacement also is performed for highly risk patients with minimally invasive, it has to resolve the problem ofbioprosthetic valve durability in future. However, there is no effective medical treatment established for AVS toinhibit acceleration of aortic valve calcification. Objectives We aimed to confirm whether the ascending aorta is the best location for AVS to innovate local and selective medicaltherapy or not. Methods and Results After anesthetized by isoflurane, the wild type rat was stablished on operating table. Opening chest to heart bymedian sternotomy approach, the catheter was inserted into left ventricular from apical for body perfusion. Weinjected saturated solution of amido black 10B （AB） into ascending aorta above sino-tubular junction about 0.5 cmfrom aortic valves without aortic dissection observed, and body perfusion was performed by saline containing heparinin order to prevent embolism happened in vascular. After 30 minutes, the heart with the ascending aorta wasextracted. We used optical microscope to check the existence of AB at around of aortic valves or not. Interestingly,AB was detected at around of aortic valves and valsalva sinus of the aorta and myocardium in all rats. Conclusions These results suggested that AB injected is delivered from the ascending aorta to aortic valves through vasavasorum. These data provide very important evidences for local medical therapy development for AVS patients.