US Patent 9498145 Cardiac event monitoring system

A cardiac event monitoring system may include a base unit including a base connector, a wearable electrode system, and a plug-in adapter. The wearable electrode system includes a cable, an electrode at one end of the cable, and a cable connector at the other end of the cable. The cable connector is configured to plug into the base connector. The plug-in adapter includes electrodes and an adapter connector that is configured to plug into the base connector. A handheld device may include a plug-in adapter having first and second electrodes and a controller that is configured to process electrical signals detected by at least one of the first or second electrodes that are indicative of a cardiac event.