CTA planimetry confirmed severe aortic stenosis AVA in 82.7% of low-flow and 76.3% of normal-flow low-gradient AS patients, supporting its use as a 4th severity criterion.
Does CTA-planimetry (pAVACTA) provide congruent severity classification compared to TTE in patients with low gradient aortic stenosis?
CTA-planimetry confirms severe aortic stenosis in a high percentage of patients with low-gradient AS, suggesting its utility as an additional diagnostic criterion when echocardiography is inconclusive.
Abstract Background Aortic valve stenosis (AS) severity as assessed by transthoracic echocardiography (TTE) can remain inconclusive when flow velocity (Vmax), mean pressure gradient (∆Pm), and calculated valve area (cAVA) are non-congruent. In particular, the combination of an cAVA1.0cm², Vmax 4.0 m/s and ∆Pm 40mmHg (low gradient (severe) aortic stenosis (LG(S)AS)) is frequently problematic. We suggest AVA by computed tomography angiography (CTA)-planimetry (pAVACTA) as a 4th severity criteria marker to aid classification. Objectives Defining the role of CTA-planimetry in LG(S)AS through integration of pAVACTA as 4th severity marker into the ESC/JASE flow-Charts for AS severity grading. Methods Patients who presented with a cAVATTE1.0cm², Vmax4m/s and ∆Pm40mmHg to our institution and underwent a pre-TAVI-CTA-scan between 2012 and 2023 were included for analysis. The role of pAVACTA as a 4th severity marker was assessed by testing for AVA severity congruence between cAVATTE and pAVACTA. Based on data from a large cohort of patients with congruent severe AS (cAVATTE1.0cm² 35ml/m², LVEF≥50%) and 173 patients with NFLG-AS (Normal Flow SVI≥35ml/m²). Congruence between cAVATTE and pAVACTA was high in both groups at 82.7% and 76.3%, respectively, with non-congruence low at 2.5% and 6.4%. Conclusion In our cohort, CTA-based planimetry confirms AVA indicative of severe AS in a high percentage of patients with LG-AS irrespective of flow. Adding pAVACTA to the diagnostic work-up as a 4th severity criteria may by useful by adding diagnostic certainty.Proposed ESC Flow Chart Modification
Voegele et al. (2025) studied this question. CTA planimetry confirmed severe aortic stenosis AVA in 82.7% of low-flow and 76.3% of normal-flow low-gradient AS patients, supporting its use as a 4th severity criterion.