Resolving Apparent Inconsistencies Between Area, Flow, and Gradient Measurements in Patients With Aortic Valve...

Inconsistencies between area (aortic valve area [AVA])-flow-gradient are common during the echocardiographic assessment of aortic stenosis (AS). This study was conducted to investigate the importance of these inconsistencies and the impact of 3 methods to resolve these inconsistencies. The study population consisted of 327 patients (age: 76.3 ± 8.6 years, 49.5% males) with severe AS (SAS) (AVA ≤ 1 cm²) and preserved left ventricular ejection fraction (≥50%). Inconsistent findings between AVA, flow, and mean gradient (MG) were observed in 78 (23.9%) patients with low flow and a high MG, 52 (15.9%) patients with normal flow and a low MG, and 37 (11.3%) patients with a low flow and a low MG. Using stroke volume index by catheterization for AVA recalculation showed the greatest effect to resolve inconsistencies in the low flow and a high MG group (85%). Decreasing the AVA cut-off values for SAS to ≤0.8 cm² resulted in a shift from SAS to moderate AS in 36 patients (69%) in the normal flow and a low MG. Indexing AVA to body surface area had only a minor impact on reclassification. In conclusion, in patients with SAS and preserved left ventricular ejection fraction, the majority of area-flow-gradient inconsistencies at echocardiography can be resolved by correcting errors in stroke volume index measurements by alternative techniques and by redefining the cut-off value for SAS to ≤0.8 cm².