Friedreich’s Sign

The normal jugular venous waveform contains two descents, x and y. The x descent, which corresponds to the combination of right atrial relaxation and depression of the atrial floor during ventricular contraction, is normally dominant. The y descent occurs as a result of passive ventricular filling during early diastole. A sharp and deep y descent that becomes more dominant than the x descent is known as Friedreich’s sign. It is associated with constrictive pericarditis and restrictive cardiomyopathy.

 

Patient 1:

This patient was admitted to the hospital with cardiac tamponade. After the effusion was drained, he developed signs of pericardial constriction, including Friedreich’s sign. The cause of the pericardial effusion was never determined, but in some cases, particularly in association with tamponade, transient acute constriction can ensue for days to weeks following the initial pericardial insult as a result of reversible inflammation and edema (transient constrictive pericarditis). These videos demonstrate a sharp and deep y descent of the jugular venous waveform. Note the comparatively smaller intervening x descent, which is normally the dominant trough of the jugular venous waveform.

Video courtesy of BMJ case reports: “Friedreich’s sign”

Friedreich’s sign

Annotated

Patient 2:

Middle-aged man with myelodysplasia, who had developed acute pericarditis several months ago, and now has effusive-constrictive pericarditis. In this video, he was in sinus tachycardia with requent premature atrial contractions, but you can appreciate his rapidly collapsing and deep Y waves

Patient 3:

This is a middle-aged man with recent orthotropic heart transplant complicated by hemorrhagic pericardial effusion who was admitted with dyspnea and elevated filling pressures along with Friedreich’s sign, concerning for constrictive physiology, perhaps subacute constrictive pericarditis.