Fast, high-resolution in vivo cine magnetic resonance imaging in normal and failing mouse hearts on a vertical 11.7 T system.

Abstract

To establish fast, high-resolution in vivo cine magnetic resonance imaging (cine-MRI) on a vertical 11.7-T MR system and to investigate the stability of normal and failing mouse hearts in the vertical position. To optimize the method on a high-field system, various MR-related parameters, such as relaxation times and the need for respiratory gating, were quantitatively investigated. High-resolution cine-MRI was applied to normal mice and to a murine heart failure model. Cardiac functional parameters were compared to matched mice imaged previously on a horizontal MR system. A T(1) of 1.10 +/- 0.27 seconds and a T(2) of 18.5 +/- 3.9 msec were measured for murine myocardial tissue. A quantitative analysis also proved respiratory gating to be essential for obtaining artifact-free cine images in the vertical position at this field strength. Cardiac functional parameters of mice, obtained within one hour, agreed well with those from previous studies of mice in the horizontal position. This work shows that MR systems with a vertical bore design can be used to accurately measure cardiac function in both normal and chronically failing mouse hearts within one hour. The increased signal-to-noise ratio (SNR) due to the higher field strength could be exploited to obtain higher temporal and spatial resolution compared to previous studies that were performed on horizontal systems with lower field strengths.