Table 2.

The new FWR clinical classification.

	Cardiac arrest type (83.3%)	Unstable type (9.0%)	Stable type (7.7%)
Main criteria	Instantaneous circulatory collapse with massive pericardial effusion and cardiac tamponade	Sudden clinical condition changes∗ with moderate/massive pericardial effusion	Hypotension with moderate/massive pericardial effusion
Additional conditions for diagnosis of FWR	None	Pericardiocentesis showing bloody fluid or no/mild pericardial effusion 24 hours ahead of FWR onset	Pericardiocentesis showing bloody fluid
Manifestations and signs	(i) Sudden loss of consciousness (ii) Cardiac arrest	(i) Patients with sudden changes in the clinical condition (such as syncope, transient arrhythmia, transient gatism, transient EMD, and sudden angina pectoris) (ii) Most patients with cardiac tamponade (jugular venous distention, muffled heart sounds, and a paradoxical pulse)	(i) Persistent hypotension or refractory angina pectoris or restlessness or no apparent symptom etc. (ii) Hypotension (iii) Some patients with cardiac tamponade (jugular venous distention, muffled heart sounds, and a paradoxical pulse)
Hemodynamic	(i) Sudden collapse	(i) Unstable and gradual worsening	(i) Stable, but may worsen
Pericardial effusion	(i) Massive pericardial effusion (ii) No/mild pericardial effusion ahead of FWR onset	(i) Moderate/massive pericardial effusion (ii) No/mild pericardial effusion ahead of FWR onset	(i) Moderate/massive pericardial effusion (ii) Pericardial effusion increased gradually
EMD	Most patients with EMD (59/65)	Some patients with EMD (3/7)	None
Get accurate rupture time	Yes	Yes	No
Hospital mortality	100%	85.7%	16.7%

^∗Syncope, transient arrhythmia, transient gatism, transient EMD, sudden angina pectoris, etc. EMD: electromechanical dissociation; FWR: free wall rupture.