Severity of stenosis and concordant/discordant indices1
A retrospective analysis was performed at a single academic medical centre on all echocardiograms with an AVA ≤1.2 cm² and Vmax ≥3 m/s from 1 December 2014 through 30 October 2017.1
- 40.0% of patients had concordant indices and 35.8% had discordant indices of AS
- Patients with discordant indices were more commonly female (54.0% vs 44.3%) compared with those with concordant indices
- 303 (93.8%) patients with concordant indices were reported as sAS
- 123 (42.6%) patients with discordant indices were reported as sAS
- 45 (49.5%) patients with discordant indices and a preserved ejection fraction ≥50% and a stroke volume index <35 mL/m² were reported as sAS
Adapted from Raddatz MA et al. Open Heart 2020.
AS assessment: Echocardiography and the integrated, stepwise approach2,3
A large challenge in AS assessment, as we have seen, is in patients demonstrating discordant indices, also referred to as ‘low-gradient AS’.
Keys to overcoming this challenge are excluding measurement errors and the utilisation of complementary diagnostic modalities alongside echocardiography.²
Most common measurement errors:
Left ventricular outflow tract (LVOT) diameter
Complementary diagnostic modalities:
- Advanced echocardiography including transoephageal echocardiography (TOE) and 3D transthoracic echocardiography (TTE)3
- Confirmation of LVOT measurements
- Confirmation of stroke volume (SV) measurements
- Dobutamine stress echocardiography3
- To distinguish between pseudo severe and sAS in patients with discordant indices and an impaired (<50%) left ventricular ejection fraction (LVEF)
- Multislice computed tomography3
- For aortic valve calcium (AVC) scoring in patients with discordant indices and preserved LVEF (≥50%) to assess the likelihood of severe AS. A calcium score of ≥2000 for men and ≥1200 for women signify that severe AS is likely
Assessing the severity of AS is challenging but is crucial in optimising treatment timing.