Aortic regurgitation is a condition in which blood flows backwards into the left side of the heart through the aortic valve. The aortic valve is a flap-like opening located between the left side of the heart and the aorta. The aorta is the main artery carrying blood from the heart.
The heart is divided into two halves, right and left. Each side has a pumping chamber, called a ventricle. The left ventricle receives blood from the lungs. During a heartbeat, the left heart chamber squeezes, generating enough pressure to open the aortic valve. Blood from the left side is then pumped into the aorta and out into the body for general circulation. As the left heart chamber empties, the aortic valve closes.
In a normal heart, the valve seals shut, and no blood is allowed to flow back into the left side. But when the aortic valve is abnormal, blood does flow backwards. This causes blood to flow into the left heart chamber from two sources. The first source is from the lungs, which is normal. The second source is from the backflow of blood across the leaky aortic valve. When the heart receives this excess amount of blood, the left side must work harder. This excess work can stress the left side of the heart and cause it to enlarge. This damage can happen slowly over time, or can get worse rather quickly.
There are many causes of aortic regurgitation. Some of the more common ones include: