Remote health monitoring is becoming increasingly important for securing independent lives as the population of aged people increases. Online, continuous monitoring allows us to detect emergencies and abrupt changes in the patient's condition. Especially for cardiac patients, online, long-term monitoring plays a pivotal role. It provides critical information for long-term assessment and preventive diagnosis for which long-term trends and signal patterns are of special importance. Such trends and patterns can hardly be identified by traditional examinations. Those cardiac problems that occur frequently during normal daily activities may disappear the moment the patient is hospitalized, causing diagnostic difficulties and consequently possible therapeutic errors. In this sense, continuous and ambulatory monitoring systems are needed to detect the traits. It is important that the ambulatory monitoring devices should be easy to wear in everyday life. Such long-term, ambulatory devices must be compact, lightweight, and comfortable to wear at all times.