Summary: Cardiac magnetic resonance imaging (MRI) has advanced to become a powerful tool in clinical practice. Extraction of morphological and functional features from cardiac MR imaging for diagnosis and disease monitoring remains a time-consuming task for clinicians. We present a fully automatic approach to extracting the structures and dynamics for both left and right ventricles. The cine short-axis stack of a cardiac MR scan is used to reconstruct a 3D volume sequence. A joint LV-RV model is introduced to delineate the boundaries of both left and right ventricles in each frame, and to combine both spatial and temporal context to track the chamber boundary motion over cardiac cycles. Both qualitative and quantitative results show promise of the proposed method.