A slow heartbeat rate is called bradycardia . A slow heart rate does not necessarily mean a patient has an underlying health problem. Athletes, for example, can have very slow resting heart rates and be perfectly healthy. If a slow heart rate, however, fails to supply the body with enough blood and oxygen, bradycardia is a severe health issue. Untreated bradycardia can lead to heart failure or sudden cardiac death. The only way to treat bradycardia long-term is to implant a pacemaker. A pacemaker is a small device that is implanted under the skin or chest muscle near the collarbone. It is connected to the heart with one or two electrodes (also called “leads”) and serves as the heart’s artificial “timekeeper.” The pacemaker continuously monitors the heart’s activity, sending electrical impulses to restore a normal rhythm if it beats too slowly or irregularly.