Basically, your aorta forces a certain amount of blood into your left ventricle every time your heart beats. If your left ventricle becomes enlarged either due to rheuamatic fever or congenitally it causes the heart to work harder than it should. To compensate for this enlargening of your left ventricle, over the years your heart has had to pump harder so that all that blood from your aorta gets into your left ventricle. Eventually just like any muscle (your heart is a muscle), the heart gets tired and doesn't pump as hard, so instead it pumps faster to further try and compensate by getting the needed amount of blood into your left ventricle. Your heart muscle is starting not to compensate as well as it used to, so now there is blood remaining in your aorta and not going into your left ventricle. Be aware if you start having difficulty breathing during minimal exertion (exertional dyspnea) or chest pain (angina) at rest or during exertion. These are not good signs for the long term. You are probably going to have a cardiac catheterization scheduled to determine the severity of this disease. I would not rule out having a valve replacement surgery down the road, but controlling your blood pressure through medications, stop smoking now if you do it, start exercising after you see your cardiologist, and watch your diet. Not gonna lie, it's something that can be controlled but it is serious.