RESUMO
BACKGROUND: Aortic valve sclerosis (AVS) is a chronic progressive disease involving lipid infiltration, inflammation, and tissue calcification. Despite its high prevalence, there are currently no clinically approved pharmaceuticals for the management of AVS. The objective of the current study was to elucidate the effects of an angiotensin II type 1 receptor blocker, alone or in combination with statin therapy, on the progression of AVS. METHODS: Male New Zealand white rabbits were fed an atherogenic diet for a period of 12 months to induce AVS. Once disease was established, rabbits were randomly assigned to receive no treatment, olmesartan medoxomil, atorvastatin calcium, or a combination of both drugs for a period of 6 months. Disease progression was monitored in vivo using clinically relevant magnetic resonance imaging, and aortic valve cusps were examined ex vivo using histologic and immunohistochemical methods. RESULTS: Cusp thickness significantly increased (0.58 ± 0.03 vs 0.39 ± 0.03 mm for cholesterol and control animals, respectively; P < 0.0001) and all classic hallmarks of disease progression-including lipid infiltration, inflammation, and tissue calcification-were observed after 12 months. Unfortunately, neither olmesartan medoxomil nor atorvastatin calcium were able to reverse or delay disease progression during the 6-month treatment period. However, several histologic changes were observed in the valvular microenvironment. CONCLUSIONS: The current study suggests that angiotensin receptor blockers, alone or in combination with statin therapy, may not be suitable for management of clinical AVS.
