Management of TAVR in asymptomatic or minimally symptomatic patients: Insights from resting angiographic microvascular resistance

Abstract

Background

The optimal timing of transcatheter aortic valve replacement (TAVR) for asymptomatic or minimally symptomatic patients with severe aortic stenosis (AS) remains controversial. Microvascular dysfunction and increased microcirculatory resistance have been linked to adverse outcomes in AS, suggesting that resting angiographic microvascular resistance (AMRr) may aid in identifying higher-risk patients.

Method

We conducted a retrospective study of 180 severe AS patients who underwent TAVR at Fuwai Hospital between 2012 and 2021. Patients were grouped based on an AMRr cutoff value of 490, identified through receiver operating characteristic (ROC) analysis. The primary endpoint was the incidence of major adverse cardiovascular events (MACE), including all-cause mortality, heart failure, and myocardial infarction. Kaplan-Meier and Cox regression analyses were used to compare outcomes between groups.

Results

A total of 180 asymptomatic or minimally symptomatic AS patients undergoing TAVR were enrolled. After a 40-month follow-up, the AMRr >490 group had a higher MACE risk, mainly driven by readmission for heart failure. Additionally, continuous analysis indicated that every 100-unit increase in AMRr was associated with an 18 %, 17 %, and 1.58-fold increased risk of MACE, all-cause mortality, and NOAF, respectively. Moreover, the addition of AMRr to a clinical model significantly improved the prediction of MACE (AUC 0.678 vs. 0.582, p = 0.023).

Conclusion

Asymptomatic or minimally symptomatic AS patients with AMRr >490 had a significantly higher incidence of MACE and heart failure rehospitalization than those with AMRr ≤490 after TAVR. The inclusion of AMRr in a predictive model improved the accuracy for long-term MACE, demonstrating an incremental prognostic value.