The peak to mean pressure decrease ratio: a new method of assessing aortic stenosis

Background: The ratio of peak to mean pressure decrease is a new measure of transaortic continuous waveform shape that could be useful for grading aortic stenosis. Methods: We retrospectively analyzed echocardiograms in 163 patients with all grades of aortic stenosis as assessed by the continuity equation. Results: The peak to mean pressure decrease ratio was 1.75 (0.14) in mild stenosis, 1.66 (0.13) in moderate stenosis, 1.56 (0.10) in severe stenosis, and 1.57 (0.07) in severe aortic stenosis with left ventricular ejection fraction less than 40%. Receiver operating characteristic curve analysis showed that a threshold of less than 1.50 gave a specificity of 94% against continuity area whereas a ratio less than 1.75 gave a sensitivity of 96%. Conclusion:The peak to mean pressure decrease ratio is a simple and quick cue to the likelihood of severe aortic stenosis in patients with low left ventricular ejection fraction when transaortic pressure decreases appear only moderate.