During which part of the cardiac cycle are artifacts explained by the magnetohydrodynamic effect most likely observed?

The magnetohydrodynamic effect, which refers to the interaction of the flowing blood within the magnetic field of an MRI scanner, typically leads to artifacts that are most pronounced during the T wave of the cardiac cycle. The T wave represents the repolarization of the ventricles and occurs after the depolarization phase represented by the QRS complex.

During the T wave, the heart is in a state where electrical activity is returning to its baseline after contraction, and blood flow can be affected by the changes in magnetic fields. This effect can lead to alterations in signal intensity as the flowing blood creates currents in the magnetic field, thus producing noticeable artifacts in the resulting images.

In contrast, the R wave is the peak of the QRS complex, representing the rapid depolarization of the ventricles. The QRS complex itself reflects active contraction, while the P wave is associated with atrial depolarization, which generally occurs earlier in the cycle. Due to the dynamics of blood flow and magnetic field interaction, the T wave is the phase where these artifacts are more significantly observed, thereby making it the most relevant point in the cardiac cycle regarding the magnetohydrodynamic effect.