The impact of hypo-attenuated leaflet thickening on haemodynamic valve deterioration following transcatheter aortic valve replacement

Background: Hypo-attenuated leaflet thickening (HALT) may occur following transcatheter aortic valve replacement (TAVR), however, it remains unclear if HALT is a predictor of haemodynamic valve deterioration (HVD). Aim: To determine the impact of HALT on the occurrence of HVD. Methods: We prospectively evaluated 186 patients for the presence of HALT at a median of 6 weeks following TAVR (Interquartile-range [IQR] 4-12 weeks). HALT depth and area were measured. HVD encompassed any of the following: mean gradient >= 20 mmHg with an increase in gradient >= 10 mmHg from baseline, Doppler velocity index reduction >0.1 or new moderate-to-severe valvular regurgitation. Routine echocardiograms at discharge, one month and annually, were assessed by echo-cardiologists that were blinded to the HALT status. Results: LT prevalence was 17.7% (33/186). HVD was present in 8.6% (16/186) at a median follow-up of 2 years (IQR 1-3); two required valve re-intervention and five required anticoagulation. HALT was the only independent predictor of HVD on multivariate analysis (OR 33.3, 95%CI 7.4-125). Patients with HALT were more likely to develop HVD, require repeat valve intervention and have higher trans-valvular gradients at up to 3-year followup. Patients with HALT had a median cumulative thickness of 2.9 mm (IQR 1.9-4.7) and area of 64.2 mm(2) (IQR 40.9-91.6). Thresholds for HALT in predicting HVD were a cumulative depth of 2.4 mm (Specificity 94.1%, Sensitivity 75.0%, AUC = 0.87) and cumulative area of 28 mm(2) (Specificity 92.2%, Sensitivity 81.3%, AUC = 0.86). Conclusion HALT is an independent predictor of HVD, which exhibits specific depth and area thresholds to predict HVD. CT following TAVR may determine patients at risk of HVD.

Automated summary

This study found that HALT is an independent predictor of haemodynamic valve deterioration (HVD), and specific depth and area thresholds were identified to predict HVD. CT following TAVR can determine patients at risk of HVD.