Abstract: Evaluating a cardiac lesion formed by an ablation procedure, by receiving, by processing circuitry and following conclusion of delivery of ablation energy, a bioelectrical signal from an electrode proximate to a target location of cardiac tissue for the cardiac lesion; determining, by the processing circuitry, one or more characteristics of the received bioelectrical signal in a frequency band of the received bioelectrical signal; and estimating, by the processing circuitry, an efficacy of the cardiac lesion based on a comparison of the determined amplitude of the bioelectrical signal and a threshold amplitude.