Arrhythmias An arrhythmia is any kind of abnormal heartbeat—too fast, too slow, or irregular. Here's information on what you can do if you have an arrhythmia. Coronary Artery Disease Coronary artery disease is primarily caused by atherosclerosis, a process in which a substance called plaque builds up on the inner walls of the arteries. Heart Attack The most common warning signs of a heart attack are a severe pressure or squeezing in the center of the chest and pain or discomfort that spreads to the shoulders, neck, or arms. Heart Valve Disease When heart valves malfunction, the implications for the heart can be serious. Heart valve problems are one cause of heart failure. Heart Failure Heart failure usually has an underlying cause. That could be high blood pressure, heart valve disease, coronary artery disease, or another problem that affects heart health. High Blood Pressure Blood pressure that's higher than normal makes the heart work harder to pump blood. If untreated, it can lead to heart failure, heart attack, or stroke. Other Heart Conditions Other problems that can affect the heart include inflammation, rheumatic heart disease, and a rare type of cancer.