Cardiac 23Na MRI

Cardiac 23Na MRI

Absolute tissue sodium concentration is elevated in myocardial infarction and has been suggested as a biomarker for cell viability. We have developed a method to quantitatively measure cardiac sodium content in rats with good spatial resolution. This method offers a new tool for studying myocardial ion homeostasis in vivo and may be of interest for different areas of cardiovascular disease, e.g. myocardial infarction, myocardial hypertrophy, but could also be used to study other organs like kidney, liver or tumours.

23Na MRI has the potential to become a new tool for assessment of myocardial viability, which can help the cardiologist to decide whether an operation will be beneficial for a particular patient suffering from coronary artery disease when used in conjunction with existing 1H MRI techniques (e.g. late Gd-enhanced MRI). However, 23Na MRI is challenging due to relatively low sodium concentrations in biological tissues, low NMR sensitivity and the short T2 of the 23Na nucleus. On the other hand, the relatively short longitudinal relaxation time (T1) of the 23Na nucleus (~30 ms), allows quantitative imaging with short repetition times (TR). For imaging of the in vivo heart, ECG-triggering is required to minimize image blurring due to cardiac motion, which poses restrictions on TR.

Research Objectives:

  • To implement and test a new 23Na chemical shift imaging method for imaging of the in vivo rat heart during several different phases of the cardiac cycle with sufficient spatial resolution.
  • To test this new method in different models of cardiovascular disease (e.g. acute myocardial infarction)

Research Methods: 23Na chemical shift imaging of live rats at 7T.

Principal Investigator: Dr Maurits Jansen

Co-Investigators: Dr Ian Marshall, Dr Gillian Gray