High-resolution longitudinal MRI of the transition to heart failure.

The development of heart failure (HF) is an evolving process that entails both structural and functional changes through time. While the physiological state of cardiac pathologies has been well characterized, less is known about the transition from a normal to a maladaptive state. Magnetic resonance imaging (MRI) is a noninvasive technique that facilitates longitudinal experiments to follow the progression of cardiac structural and physiological disorders over time. Transgenic murine models of cardiac disease, such as the muscle LIM protein-deficient strain used in this study, offer populations of a reproducible phenotype that readily lend themselves to serial studies. In this longitudinal study, high spatial and temporal resolution time-course MR images revealed an abrupt and brief phase of major anatomical restructuring during which the ventricular chamber dilated and the wall thinned. The ability of MRI to acquire spatially and temporally resolved images enabled the 3D estimation of cavity volume and wall mass changes with time. It was concluded that, using an imaging protocol of high temporal resolution, MRI has the adequate spatial and temporal imaging resolution to allow for the detection and quantification of rapidly occurring transitional phases in a single mouse heart as it progresses toward failure.