Candiovascular System Arry thmias A heart arrhythmia is an irregular heartbeat rhythm caused by the electrical impulses that contro the heart's rhythm. In other words, the internal conduction system of the heart is not properly functioning. An arrythmia may cause the heart to beat too fast (tachycardla), too slow (bradycardla), or in an Irregular pattern, potentially affecting the heart's ability to pump blood and deliver oxygen to tissues effectively. Arrhythmias can vary in severity, ranging from harmless and brief irregularities to potentially life-threatening conditions. 1. What occurs within the cardiovascular system to cause an arrythmia? 2. square .