Abstract: Devices and methods are described for treatment of cardiac arrhythmias, particularly atrial fibrillation. A three-dimensional computer model of the patient's heart produced from imaging data is used to fabricate a personalized or patient-specific customized ablation catheter. The personalized ablation catheter is shaped to fit the unique anatomy of the patient's left atrium and has ablation elements that correspond with each of the patient's pulmonary vein ostia. Ostial fitment elements engage the ostia to align the ablation elements and a base ring attached by spring members urges the ablation elements into apposition with the inner wall of the left atrium. A neuroprotective mesh is attached across the ring to capture and remove potential emboli. Ablation energy, such as radiofrequency energy, is applied through the ablation elements. Electrodes located on the personalized ablation catheter are used to verify electrical isolation of the pulmonary veins at the completion of the procedure.