Background: Peak aortic valve Doppler velocity, mean aortic valve gradient, and Doppler estimated aortic valve area are key measures recommended for assessing aortic stenosis severity. Discordance often occurs among these measures, posing diagnostic challenges. Failure to accurately diagnose severe aortic stenosis is critical. This study focuses on the discordance between reported aortic valve area (AVA) and stenosis severity, comparing guidelines from the ASE and ACC seen in Table 1. Goals: Assess the incidence of discordance between reported AVA and severity of aortic stenosis and compare how the differing guideline recommendations of the ASE versus ACC for defining severe AS by AVA would affect reporting severity in a large clinical practice. Methods: A query of all transthoracic echocardiograms obtained in patients 18 years of age and above was performed in a large multi-hospital healthcare system between Jan 1 and Jun 30 of 2023. This group was then filtered to include only exams in which the reported aortic valve area was 1 cm2 or less, excluding all cases with prosthetic aortic valves. This group was then further filtered to contain only those patients in whom the physician did NOT report severe aortic stenosis. Results: Between Jan and June 2023, 16,675 subjects ages 18-95 (avg 74) underwent transthoracic echocardiograms in our healthcare system, with 190 (1.1%) reported as having an AVA ≤ 1 cm2. Of those exams, 63 (33% of those with AVA ≤ 1) were not reported as having severe aortic stenosis. Of those 63 exams, 35 (56%) had a reported SVI < 35 ml/m2 compatible with a low flow state. However, only 1 of those 35 cases mentioned flow-status in labeling the stenosis severity in the report. Based on the ASE Doppler AVA definition of severe AS (< 1.0 cm2 (≤ 0.94 )) vs ACC (≤ 1 cm2 (≤1.04), the AV Doppler and SVI data contained in the reports should have led to the grading of the aortic valve as being ”Severe” or “Moderate” aortic stenosis as described in Table 2. Conclusion: Discordance in labeling severe aortic stenosis relates to differing AVA criteria. Cases are often termed "moderate to severe" under ACC criteria. The majority (56%) of cases failing to describe severe AS despite meeting AVA criteria were in low flow states, suggesting this phenomenon is not well understood in clinical practice. Various factors contribute to these findings, warranting further investigation.
Read full abstract