This paper presents a wavelet-based framework for enhancing the coherent structures attributable to the target organ in cardiac Magnetic Resonance (MR) images. Previous approaches focus on the Rician nature of noise in magnitude MR images. Image noise is but only one of the confounding factors that obscure the anatomical structures of the target organ. This paper models the image noise in a magnitude MR image in terms of two noise classes which occur over different ranges of signal intensity. An adaptive enhancement scheme is developed to achieve simultaneous attenuation of the effects of these factors and improvement in image contrast.