What is one of the criteria for defining CFAE signals?

The criteria for defining Complex Fractionated Atrial Electrograms (CFAE) signals include particular characteristics that differentiate them from other atrial signals. One of the key defining characteristics of CFAE signals is a low amplitude, particularly with magnitudes that can be less than 0.25 mV. This low-voltage activity reflects disorganized electrical activity in the atria, which is a hallmark of conditions like atrial fibrillation.

In contrast, other options do not accurately describe CFAE criteria. Higher amplitudes, such as those above 0.5 mV, would not typically fit the CFAE profile, nor would durations that are shorter than 30 ms, as CFAE signals often have prolonged durations indicative of complex fractionation. Continuous activity without any deflections might suggest a different form of electrical activity that doesn’t characterize CFAE. Hence, the defining feature of a magnitude less than 0.25 mV captures the essence of CFAE signals accurately.