Neointimal hyperplasia is the principal mechanism of graft failure in coronary artery bypass surgery. Systemic administration of cilostazol has been reported to suppress neointimal hyperplasia in some vascular injury models. We sought to deliver cilostazol locally in an attempt to augment its beneficial effect to inhibit neointimal hyperplasia at an anastomotic site. We examined whether the external application of a novel cilostazol-eluting film can inhibit neointimal hyperplasia in a vascular anastomosis model. Canine femoral artery graft interposition was performed in 20 beagle dogs, assigned to 4 groups of 5 dogs each : a graft interposition without copolymer of L-lactide and ε-caprolactone (P (LA/CL) ) film (control group) and groups with P (LA/CL) film containing cilostazol of either 10 mg, 40 mg, or 80 mg doses. All the cilostazol-eluting film with 10 mg, 40 mg, and 80 mg dose groups had a reduced intima/media ratio compared to the control group (0.15±0.03, 0.11±0.03, and 0.12±0.03, vs. 0.31±0.03, p<0.05). Immunohistochemical analyses for proliferating cell nuclear antigens revealed reduced cellular proliferating activity associated with decreased α-actin positive cells in the cilostazol-eluting film groups compared to the control group. External application of cilostazol-eluting film can inhibit neointimal hyperplasia, at least in part, by inhibiting smooth muscle cell proliferation in the intima.

A 70-year-old female with a pulmonary embolism was admitted to a local hospital. On admission, transthoracic echocardiography detected a mobile cardiac tumor on the aortic valve. After medical treatment for a pulmonary embolism, she was slated for a resection of the tumor in our hospital. Although preoperative examinations showed an isolated tumor attached to the non-coronary cusp without valve dysfunction, meticulous intraoperative inspection revealed multiple fine villous tumors located in the left coronary cusp of the aortic valve. Being immersed in saline solution, these tumors had resembled a distinctive sea anemone-like appearance. These fine tumors could not be detected with intraoperative transesophageal echocardiography even in a retrospective manner. We eventually performed aortic valve replacement. The tumors of the two cusps were pathologically diagnosed as papillary fibroelastoma. Of note, a macroscopically undetected tumor was identified in the right coronary cusp by histopathological evaluation. Careful intraoperative observation is essential for surgical decision and patient’s prognosis. It is also considered that latent tumor might be concealed even in seemingly normal adjacent cusps in a case with multiple papillary fibroelastomas.