Mitral regurgitation is a condition in which disease or injury has caused the heart’s mitral valve to become leaky. The four heart valves function as one-way valves, allowing blood to be pumped forward and preventing blood from regurgitating backwards. When the mitral valve becomes leaky, blood may back up into the lungs, causing shortness of breath. An untreated leaky valve can lead to heart failure.
In patients with mitral regurgitation, the lungs become congested with fluid. As fluid accumulates in the lungs, it interferes with the absorption of oxygen from the lungs into the bloodstream. This leads to shortness of breath. Some patients feel short of breath when they exercise or exert themselves. Others they lie down at night. They may need to sleep with their heads elevated to avoid waking up in the middle of the night feeling short of breath.