Erica Dall'Armellina1, Craig A. Lygate1, Hannah Barnes1, Ricardo Carnicer1, Stefan Neubauer1, Michael Markl2, Bernd A. Jung2, Jurgen E. Schneider1
1Department of Cardiovascular Medicine, University of Oxford, Oxford, Oxon, UK; 2University Hospital Freiburg, Freiburg, Germany
Direct intra-myocardial injections are often used for viral gene transfer experiments in the mouse, however, myocyte transfection by this route is inhomogeneous, localised mainly around the sites of injection. Tissue phase mapping (TPM) could be a useful tool to detect small changes to regional function in vivo after direct injection of genetic material. However, it is first necessary to determine whether the surgical intervention required injecting the heart, has itself an effect on regional cardiac function and on baseline TPM parameters. We have therefore used TPM longitudinally in the same mouse to track changes in regional function at baseline, and 24 hours and 8 days after direct intra-myocardial injection of saline. We found that only the anterior wall exhibited a relative impairment in regional function after surgery, which may be related to the removal of the pericardium rather than the injection. Importantly, no change in global cardiac function (i.e. ejection fraction (EF) and stroke volume (SV)) could be detected