The present invention deal with a process to obtain a decoction from Vitis Labrusca and Vitis skins; process to obtain a hydro-alcoholic and hydro-alcoholic-ethyl acetate obtained from the decoction; pharmaceutical preparations containing the decoction and the before mentioned extracts and therapeutic utilization of the preparations and the prevention and treatment of arterial hypertension and other cardiovascular diseases. The decoctions and the extracts, when administered orally to rats with spontaneous arterial hypertension, hypertension induced by chronically inhibition of nitric oxide synthesis or induced by DOCA-salt administration induced a significant reduction of the high levels of arterial blood pressure. Capsules and tablets were prepared with the decoctions and extracts.