Mitral regurgitation means the valve between the left upper and lower heart chambers doesn’t seal, so blood leaks backward. Mild leaks are silent; bigger ones shout through your lungs and energy level. Shortness of breath is the star. You puff climbing one flight of stairs or can’t finish a sentence while walking. Fatigue creeps in. Legs feel heavy, and you need to sit after light chores that used to be easy. Night-time cough or wheezing shows up. Fluid backs up into the lungs, so you wake up gasping or need extra pillows. Heart flutter or skipped beats are common. You... Learn more