. Beck's Triad Is seen in -

Beck's triad is a pathognomic feature of cardiac tamponade Beck's triad is a collection of three medical signs associated with acute cardiac tamponade, an emergency condition wherein fluid accumulates around the hea and impairs its ability to pump blood. The signs are low aerial blood pressure, distended neck veins, and distant, muffled hea sounds. Ref Harrison 20th edition pg 1416