Is Paravalvular Leak the Achilles Heel of TAVR and How to Obtain Best Outcomes

Proceedings from 12th Biennial Meeting of the International Andreas Gruentzig Society:  Brazil – 2014

From SESSION 2 — Structural
    Moderator:      Jim Zidar
    Panelists:      Steve Bailey, Robert Bersin, Larry Dean, Bill O’Neill

Framing the question at hand, what is the state of the current knowledge?

The explosive growth of TAVR as an alternative to open AVR has led to efforts to optimize clinical outcomes for this group of elderly patients with many co-morbid conditions.  While early analysis of para-valvular leak has drawn the greatest attention as a predictor for poor long-term outcomes, there is no widely accepted standard for AR quantification. In addition, there is no indication that valve type makes a difference in the amount or frequency of AR.  Newer valves are moving through clinical trials on an international front that could address this important clinical issue.

What are the Gaps in the current knowledge?

Is paravalvular leak an independent predictor of worse outcome or simply a marker for more complex disease? Valve calcification is often asymmetric and may worsen valve apposition.  Many patients have an oval aortic valve orifice that does not completely conform to a round balloon expandable valve. Could we rely on 3D echo and/or quantification with regurgitant volume calculations as a means to standardize the current  qualitative assessment of AR?  Should a validation study be completed of patients with >mild AR to assess whether continued medical therapy vs. closure of the paravalvular leak results in a superior clinical outcome?

Our Summary and Recommendations:

Continued research is required to address the shortcoming of the current clinical devices with a more consistent way to assess AR from paravalvular leak. Biomarkers such as pro-BNP may identify higher risk patients. Second generation devices should be compared to first generation for the incidence of AR. The field needs to move away from general anesthesia to smaller devices using a transfemoral approach. ICE may need to replace TEE for proper valve positioning under conscious sedation techniques. Large vessel closure devices should make open femoral cut-downs obsolete. When AR from paravalvular leak becomes significant, specifically designed devices to correct the leak would essential to move the field forward.