Mitral Valve Prolapse Mitral valve prolapse is a deformity of the mitral valve that can sometimes produce mitral regurgitation. Mitral valve prolapse produces a sound called a heart murmur that a doctor can hear through a stethoscope. This condition is…
Aortic Stenosis Aortic stenosis occurs when the aortic valve (the valve between the aorta and the left ventricle) becomes abnormally thick or the valve flaps (leaflets) become stuck together, narrowing the opening. The aorta is the artery through which the…
Mitral Regurgitation If the mitral valve does not close properly, the blood circulating through the heart may leak back into the left atrium (one of the two upper chambers of the heart) from the left ventricle (one of the two…
Mitral Stenosis Mitral stenosis occurs when the mitral valve, which is located between the left atrium (one of the two upper chambers of the heart) and the left ventricle (one of the two lower, pumping chambers of the heart), becomes…
Paroxysmal Atrial Tachycardia In healthy adults, the heart beats from 60 to 100 times per minute, and increases to about 160 beats per minute during physical activity. In an episode (or paroxysm) of atrial tachycardia, the heart rate suddenly jumps…
Heart Block The heart rate is controlled by a natural pacemaker called the sinoatrial node, a group of specialized cells in the wall of the right atrium (the upper right chamber of the heart). The sinoatrial node transmits electrical impulses…
Ectopic Heartbeats Ectopic heartbeats are irregular beats among otherwise normal heartbeats that feel as though the heart has either missed or gained a beat. This condition is common and usually does not require treatment. If you are bothered by an…
Atrial Fibrillation and Flutter In atrial fibrillation and flutter, the atria (the two upper chambers of the heart) contract (beat) irregularly and are not synchronized with the contractions (beating) of the ventricles (the two lower, pumping chambers of the heart).…
Cardiac Arrest Cardiac arrest means that the heart is beating ineffectively or has stopped beating. Possible causes of cardiac arrest include ventricular tachycardia (a rapid, ineffective heartbeat originating in the ventricles), ventricular fibrillation (a disorganized, ineffective attempt by the ventricles…
Arrhythmias A normal heart rate for a person who is resting is between 60 and 100 beats per minute, with some minor variations. The two major types of arrhythmias are bradycardias, in which the resting heartbeat is slower than 60…