St. Jude Medical, Inc. designs, manufactures, and distributes cardiovascular medical devices and implantable neurostimulation devices worldwide. It operates in four segments: Cardiac Rhythm Management, Cardiovascular, Atrial Fibrillation, and Advanced Neuromodulation Systems. The Cardiac Rhythm Management segment offers products for cardiac arrhythmias, or irregular heart beats. Its products include tachycardia implantable cardioverter defibrillator systems to provide therapy to patients suffering from lethal heart conditions, such as sudden cardiac arrest; cardiac resynchronization therapy devices to treat heart failure patients; pacemakers to help people whose hearts beat too slowly or who suffer from other cardiac arrhythmias; and leads, which connect devices to the heart and carry the electrical impulses to the heart and information from the heart back to the device. The Cardiovascular segment provides mechanical and tissue replacement heart valves, as well as heart valve repair products. It also offers disposable interventional devices, including vascular closure devices, patent foramen ovale closure devices, embolic protection systems, wire control catheters, percutaneous catheter introducers, diagnostic guidewires, and temporary bipolar pacing catheters. The Atrial Fibrillation segment provides a system of products for access, diagnosis, visualization, and ablation that assist physicians in diagnosing and treating various irregular heart rhythms. This segment offers electrophysiology introducers and catheters, cardiac mapping and navigation systems, and ablation systems. The Advanced Neuromodulation Systems segment offers a range of neurostimulation systems, including rechargeable implantable pulse generators, conventional implantable pulse generators, and radio frequency powered systems. St. Jude Medical markets its products through a direct sales force and independent distributors. The company was founded in 1976 and is headquartered in St. Paul, Minnesota.