Outcomes and Predictors of Different Flow-Gradient Patterns of Aortic Stenosis Following Transcatheter Aortic Valve Replacement

This study sought to explore the clinical factors associated with classical low-flow low-gradient (C-LFLG) and normal-flow low-gradient (NFLG) aortic stenosis (AS) compared to high-gradient (HG) AS. We also compared clinical and echocardiographic outcomes after transcatheter aortic valve replacement (TAVR) across flow-gradient patterns. Patients with C-LFLG AS have a higher mortality rate after TAVR than those with HG AS. However, what leads to C-LFLG AS and the predictors of mortality in this population remain unclear. In this retrospective, single-center study involving 1415 patients with severe AS, patients were classified into: 1) HG: (aortic valve mean gradient [MG] >40 mmHg); 2) C-LFLG, MG <40 mmHg, stroke volume index (SVI) <35 ml/m², left ventricular ejection fraction (LVEF) <50%; 3) NFLG: MG <40 mmHg, SVI ≥35 ml/m², LVEF ≥50%. Logistic regression was used for predictors of C-LFLG AS. Cox regression was used for predictors of mortality in the C-LFLG AS population. Male sex, multiple comorbidities, and moderate to severe mitral and tricuspid regurgitation (MR, TR) correlated with the C-LFLG AS group. Patients with C-LFLG AS had a higher mortality risk compared to HG AS at 2-years post-TAVR. Patients with NFLG AS had similar mortality at 1-year, but higher mortality at 2 years post-TAVR compared to HG AS. End-stage renal disease, atrial fibrillation, and other comorbidities predicted 2-year mortality in patients with C-LFLG AS. In conclusion, mortality after TAVR was higher in C-LFLG patients compared to HG. Male sex and multiple comorbidities predicted C-LFLG AS. Multiple comorbidities predicted mortality in those patients.