Symptomatic Low Gradient Severe Aortic Stenosis with Preserved Left Ventricular Ejection Fraction: Now Less of a Clinical Conundrum
Accurate assessment of aortic stenosis (AS) severity is one of the more technically demanding studies in echocardiography. This is reflected in the Intersocietal Accreditation Commission for Echocardiography's standards that specify that aortic stenosis gradients must be measured from at least 3 different transducer positions as well as with a non-imaging dedicated continuous wave Doppler transducer (Pedhoff). The standards do not specify the measurement of any other valvular lesion. Submission and review of aortic stenosis cases is required for lab accreditation by that body. Given the complexity in echocardiographic assessment, the determination that a patient has severe aortic stenosis (defined as a valve area ≤ 1 cm2 or an indexed area ≤0.6 cm2/m2) but a mean gradient < 40 mm Hg despite a preserved LV ejection fraction (LVEF) is often met with skepticism by our interventional colleagues. Low gradient severe AS due to decreased LV systolic function can be assessed by dobutamine protocols intended to increased the flow across the valve and distinguish true from pseudo-AS.1 Such is usually not the case in patients with preserved LVEF.
- Received June 24, 2013.
- Accepted June 25, 2013.