Methods: We reclassified the aortic stenosis(AS) severity of the participants of the PRIMID-AS study, using the 2017 guidelines, determined their risk of reaching a clinical endpoint (valve replacement for symptoms, hospitalisation or cardiovascular death) and evaluated the prognostic value of aortic valve(AV) Calcium score and biomarkers. Patients underwent echocardiography, cardiac magnetic resonance imaging, exercise tolerance testing (ETT) and biomarker assessment.
Results: Of the 174 participants, 45% (56/124) classified as severe AS were reclassified as moderate AS. This Reclassified group was similar to the original moderate group in clinical characteristics, gradients, calcium scores and remodelling parameters. There were 47 primary endpoints (41 valve replacement, 1 death, 5 hospitalisations - 1 chest pain, 2 dyspnoea, 1 heart failure, 1 syncope) over 368±156 days follow-up. The severe and Reclassified groups had higher risk compared to moderate group (adjusted hazard ratio 4.95 (2.02-12.13) and 2.78 (1.07-7.22) respectively), with the Reclassified group demonstrating an intermediate risk. A mean pressure gradient (MPG)≥31mmHg had a 7× higher risk of the primary endpoint in the Reclassified group. AV Calcium score was more prognostic in females and low valve area, but not after adjusting for gradients. NTproBNP and myocardial perfusion reserve were associated with the primary endpoint, but not after adjusting for positive ETT. Troponin was associated with cardiovascular death or unplanned hospitalisations.
Conclusions: Reclassification of asymptomatic severe AS into moderate AS was common using ESC 2017 guidelines. This group had an intermediate risk of reaching the primary endpoint. Exercise testing, multi-modality imaging and lower MPG threshold of 31mmHg may improve risk stratification.
Clinical Trial Registration Information: clinicaltrials.gov - NCT01658345.
- aortic stenosis
- aortic valve calcification
- exercise tolerance test
- calcium score
- aortic valve
- heart disease