causes of fluid pounding
Buildup of excess fluid in body tissues (edema) ...swelling in the feet, ankles, legs or abdomen or weight gain. You may find that your shoes feel tight. As blood flow out of the heart slows, blood returning to the heart through the veins backs up, causing fluid to build up in the tissues. The kidneys are less able to dispose of sodium and water, also causing fluid retention in the tissues. Tiredness, fatigue.
When the left ventricle fails, fluid backs up in the lungs. In turn, pressure from excess fluid can damage the heart's right side as it works to pump blood into the lungs. Heart failure usually is a chronic, or long-term, condition that gradually gets worse.