Advanced 400 mr system

Mice were anesthetized with isoflurane (2%) and imaged in a vertical 9.4-T, 89-mm bore size magnet equipped with 1500 mT/m gradients and connected to an advanced 400 MR system (Bruker Biospin) using a quadrature-driven birdcage coil with an inner diameter of 3 cm. Respiration and ECG were continuously monitored and maintained at 20–60 breaths per minute and 400–600 bpm, respectively. ParaVison 4.0 and IntraGate software (Bruker Biospin GmH) were used for cine MR acquisition and reconstruction. After orthogonal scout imaging, short-axis (oriented perpendicular to the septum) cardiac cine MR images were acquired. Semi-automatic contour detection software (CVI^{42 (link)}, version 5.6.6, Circle Cardiovascular Imaging, Canada) was used for the determination of the LV end-diastolic volume, LV end-systolic volume, stroke volume, and ejection fraction (EF), as described^{53 (link)}.

Cardiac MRI measurements have been previously described in more detail [12 (link)]. After anesthesia with 2% isoflurane, mice were placed in a vertical 9.4-T, 89-mm bore size magnet equipped with 1500 mT/m gradients and connected to an advanced 400 MR system (Bruker Biospin) using a quadrature-driven birdcage coil with an inner diameter of 3 cm. With the ECG Trigger Unit (RAPID biomedical GmBH), respiration and heart rate were registered. Respiration rate was kept between 20–60 breaths per minute and heart rate between 400–600 beats per minute. Cine MR acquisition and reconstruction was performed with ParaVison 4.0 and IntraGate software (Bruker Biospin GmH). For mice with ischemic heart failure, 8–9 slices were needed for cardiac cine MR images and 7 for control animals. The software QMass (version MR 6.1.5, Medis Medical Imaging Systems) was used to obtain the left ventricular (LV) end-diastolic volume (LVEDV), LV end-systolic volume (LVESV) and LV ejection fraction (LVEF).