Symptoms and Signs of Cardiac Tamponade Classically, patients have Beck's triad, which consists of the following: Hypotension Muffled heart tones Venous pressure increase (eg, neck vein distention) However, hypotension has multiple potential causes in trauma patients, muffled heart tones can be difficult to assess during a noisy trauma resuscitation, and neck vein distention can be absent due to hypovolemia.