Is peripheral arterial pressure a satisfactory substitute for ascending aortic pressure when measuring aortic valve gradients?
Substitution of peripheral arterial pressure for ascending aortic pressure is a common but poorly validated practice in the assessment of aortic valve gradients by catheterization. The accuracy of this practice was assessed by comparing the left ventricular-ascending aortic mean gradient in 26 cases of aortic stenosis with the left ventricular-femoral artery gradient, both with and without compensation for temporal delay in femoral artery pressure. Aligned left ventricular-femoral artery gradients (matching upstrokes to compensate for peripheral time delay) underestimated the left ventricular-ascending aortic gradient by 10 mm Hg (range 0 to -17). Unaltered simultaneous left ventricular-femoral artery gradients overestimated the left ventricular-ascending aortic gradient by an average of 9 mm Hg (range +1 to +18). For both peripheral techniques, the error was relatively constant throughout the range of aortic valve gradients. The most accurate estimate of both aortic valve gradient and
