The Beck triad, described in 1935 by Claude Beck, includes two characteristic triads for acute and chronic cardiac compression. In acute cardiac tamponade, the presence of the full triad of distended neck veins, diminished heart sounds, and hypotension is uncommon, occurring in only 10% to 40% of patients. Hypotension is present in 14% to 35% of patients, diminished heart sounds in 24% to 34%, and elevated jugular venous pressure in 53% to 88%. The most common presenting symptom in patients with symptomatic pericardial effusion requiring drainage is dyspnea (87%-88% sensitive), and the most sensitive and specific physical finding is pulsus paradoxus (98% sensitive, 83% specific with a >12 mm Hg change in pressure). Other signs and symptoms are listed in Table 12.4. Patients with loculated effusions or regional cardiac tamponade can present with very few or with an atypical constellation of these signs and symptoms.

The chronic cardiac compression triad consists of elevated jugular venous pressure, ascites, and diminished heart sounds. Beck described these signs in patients with tuberculous, idiopathic pericarditis, or constrictive pericarditis without effusion. The shift from hypotension to ascites reflects the longer-term restriction of venous return to the RA and RV, thereby leading to chronic passive hepatic congestion.

Hypertensive cardiac tamponade is an unusual variant thought to result from the sympathetic response to impaired cardiac filling in patients who develop cardiac tamponade over days to weeks. These patients challenge the classic aphorism of cardiac tamponade being a clinical diagnosis, with average systolic pressures of between 127 and 144 mm Hg at presentation based on six retrospective reviews including 239 patients. These patients all had echocardiographic criteria consistent with cardiac tamponade, including right atrial and RV collapse and exaggerated respiratory variation of RV and LV inflow velocities. Draining the effusion leads to normalization of blood pressure.

References

• Argulian E, Herzog E, Halpern DG, et al. Paradoxical hypertension with cardiac tamponade. Am J Cardiol. 2012;110:1066-1069.
• Argulian E, Messerli F. Misconceptions and facts about pericardial effusion and tamponade. Am J Med. 2013;126:858-861.
• Jacob S, Sebastian JC, Cherian PK, et al. Pericardial effusion impending tamponade: a look beyond Beck's triad. Am J Emerg Med. 2009;27:216-219.
• Roy CL, Minor MA, Brookhart MA, et al. Does this patient with a pericardial effusion have cardiac tamponade? JAMA. 2007;297:1810-1818.