Methods for estimating of the effectiveness of catheter ablation procedures to form lesions. Lesion effectiveness parameters are received, and effectiveness of a corresponding ablation (optionally planned, current, and/or already performed) is estimated. The estimating is based on use by computer circuitry of an estimator constructed based on observed associations between previously analyzed lesion effectiveness parameters, and observed lesion effectiveness. The estimator is used by application to the received lesion effectiveness parameters.