What is the condition known as when excess fluid compresses the heart?

Tamponade is a condition characterized by the accumulation of excess fluid in the pericardial space, which surrounds the heart. This fluid buildup creates pressure on the heart, restricting its ability to pump effectively. As the pressure increases, it leads to a decrease in the heart's filling capacity during diastole, potentially resulting in decreased cardiac output. Symptoms of cardiac tamponade can include shortness of breath, tachycardia, hypotension, and a characteristic triad of findings known as Beck's triad: hypotension, muffled heart sounds, and distended neck veins. This condition is typically considered a medical emergency and may require immediate intervention, such as pericardiocentesis, to relieve the pressure and restore normal heart function.

Myocarditis involves inflammation of the heart muscle itself, causing various symptoms but does not specifically refer to fluid accumulation around the heart. Cardiomyopathy refers to diseases of the heart muscle, affecting its size, shape, or thickness, while pericarditis is inflammation of the pericardium that can sometimes lead to fluid accumulation but does not inherently describe the compression of the heart caused by excess fluid.