Methods: Catheterization of the coronary sinus (CS) from the femoral vein is widely used during electrophysiologic procedures. Access to the CS may be difficult. To address this problem we explored the utility of a long pre-formed (SAFL™) sheath in a cohort of consecutive patients requiring CS cannulation in the electrophysiology laboratory. This unique sheath has distal curvatures in 2 planes, potentially facilitating CS cannulation.Results: 68 patients were studied with an average age of 63±16 years. In twelve patients (18%), standard femoral CS cannulation was ineffective. In six of these patients, the SAFL™ sheath allowed for cannulation, and in six the subclavian approach was required. There were no significant differences in age, left ventricular ejection fraction, or echocardiographically estimated pulmonary artery systolic pressure between the various subgroups. There was a trend towards a larger left atrial size in the atrial flutter group (46mm±7.9) versus all others (40.6mm±6.3, P=.076). Left atrial size was 37 mm in the femoral sheath-requiring group versus 44 mm in all others (P=NS).Conclusion: Utilization of a unique commercially available long preformed sheath helps to provide femoral CS catheter access in selected cases in the electrophysiology laboratory