<prompt> Water can appearance of heart shadow in a Chest X-ray is seen inPericardial effusionTetralogy of FallotEbsteins anomalyHypertropic cardiomyoathy E. F.  <response>: A Pericardial effusion PERICARDIAL EFFUSION defines the presence of an abnormal amount andor character of fluid in the pericardial space. It can be caused by a variety of local and systemic disorders, or it may be idiopathic. Pericardial space normally contains 15-50 mL of fluid, which serves as lubrication for the visceral and parietal layers of the pericardium. This fluid is thought to originate from the visceral pericardium and is essentially an ultrafiltrate of plasma. Total protein levels are generally low; however, the concentration of albumin is increased in pericardial fluids owing to its low molecular weight. Classic Beck triad of pericardial tamponade hypotension, muffled heart sounds, jugular venous distension Pulsus paradoxus: Exaggeration of physiologic respiratory variation in systemic blood pressure, defined as a decrease in systolic blood pressure of more than 10 mm Hg with inspiration, signaling falling cardiac output during inspiration. Pericardial friction rub:The most important physical sign of acute pericarditis may have up to 3 components per cardiac cycle and is high-pitched, scratching, and grating. Ewart sign - Dullness to percussion beneath the angle of left scapula from compression of the left lung by pericardial fluid Chest radiography Findings include enlarged cardiac silhouette so-called water-bottle heart or flask, pericardial fat stripe. A third of patients have a coexisting pleural effusion. Echocardiogram This is the criterion standard for noninvasive diagnosis. Pericardial effusion appears as an echo-free space between the visceral and parietal pericardium 