Prognostic and therapeutic implications of a low aortic valve calcium score in patients with low-gradient aortic stenosis.

AIMS

Low-gradient (LG) aortic stenosis (AS) poses a diagnostic challenge. Aortic valve calcium score (AVCS) assessment has emerged as a complementary diagnostic method when echocardiography provides discordant results. However, the diagnostic and prognostic values of AVCS in LGAS have not been thoroughly studied. Our aims in this study were to investigate the prognostic importance of AVCS in LGAS and to assess whether symptomatic patients with LGAS and low AVCS may benefit from aortic valve intervention (AVI).

METHODS AND RESULTS

A total of 327 symptomatic patients (78.5 ± 7.3 years, 51% women) with severe AS defined by the aortic valve area who underwent computed tomography for transcatheter aortic valve intervention (TAVI) planning were enrolled. AVCS was measured. AVCS < 2000AU in men and < 1200 AU in women was considered a low AVCS. A total of 243 patients had high gradient (HG) and 84 had LGAS. A low AVCS was present in 25 (10%) patients with HG and 34 (40%) with LGAS. Over a median follow-up period of 4.9 years, 194 deaths occurred. In multivariate analysis, AVCS was a significant independent predictor of all-cause mortality among patients with HGAS [adjusted hazard ratio (aHR): 2.317; CI: 1.104-4.861; P = 0.026] but not among those with LGAS (aHR: 0.848; CI: 0.434-1.658; P = 0.630). After propensity score matching between patients who underwent AVI and those who were medically treated, AVI (94% TAVI) was a significant and independent predictor of survival among LGAS patients with a low AVCS even after adjustment for clinical variables (aHR: 0.102, CI: 0.028-0.369; P < 0.001).

CONCLUSION

The prevalence of a low AVCS is much higher in patients with LGAS than in those with HGAS. In patients with symptomatic severe LGAS, a low AVCS does not entail a better prognosis. AVI is equally beneficial in LGAS patients with a high or low AVCS, similarly to those with HGAS.