hypotension and valvular dysfunction: chicken or the egg?

CASE PARTICULARS:

--SOB, hypotension

--labs notable for slightly elevated troponin, AKI

DIAGNOSTICS:

--could not undergo CTPA to r/o PE due to AKI
--ECHO in ED shows no RV dilation but did show severe MR and TR.
--pt intubated secondary to massive fluid resuscitation

--ECHO following day was normal. 

--Once rehydrated, pt did much better.  No PE was found on CTPA.

WHAT HAPPENED?

--hypovolemia exacerbated systolic anterior motion of mitral valve causing severe dynamic MR and TR, causing cardiogenic shock. 

TEACHING POINTS:
--This patient had LV outflow tract obstruction by a hyperdynamic anterior motion of the mitral valve leaflets during systole, causing a severe mitral regurgitation due to the blockage of the outflow tract as well as opening of the mitral valve during systole. 

--This mimics HOCM, but was in a structurally normal heart. 
--Obstructive physiology, and especially systolic anterior motion of the mitral valve, can be caused by various disorders including hypercontractile states such as hypovolemia, anemia, beta agonist drugs, D-transposition of the great arteries, congenital/acquired abnormalities of the mitral valve/papillary muscles, and immediately after aortic valve surgery for aortic stenosis (due to acute afterload reduction).

10-SECOND TAKEAWAY:

--suspect massive PE, can’t to CTPA, think of bedside echo to look for RV dilation/strain

--severe hypercontractile states (e.g. hypovolemia) can result in obstructive physiology, including valvular dysfunction

--can be transient, should improve with fluids (good idea for treatment)

Submitted by T. Boyd.

Refence(s): Rosen B et al. “Hypovolemia-Induced Reversible Severe Mitral Regurgitation Due to Left Ventricular Outflow Tract Obstruction.” Echocardiography. 19:8; Nov. 2002.