The impact of respiratory motion on electromagnetic fields and specific absorption rate in cardiac imaging at 7T.

Respiratory motion does not only affect the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msubsup><mml:mi>B</mml:mi> <mml:mn>1</mml:mn> <mml:mo>+</mml:mo></mml:msubsup> </mml:mrow> <mml:annotation>$$ {B}_1^{+} $$</mml:annotation></mml:semantics> </mml:math> distribution and hence the image contrast, but also location and magnitude of the peak spatial SAR. Therefore, respiration effects may need to be included in safety analyses of RF coils applied to the human thorax.