Is TAVR (Transcatheter Aortic Valve Replacement) a suitable treatment option for patients with severe aortic regurgitation?

TAVR for Severe Aortic Regurgitation

TAVR is not currently recommended for severe aortic regurgitation due to insufficient evidence to establish a favorable risk-benefit ratio, and additional scientific data must be collected before integration into routine clinical care. 1

Guideline Position on TAVR for Aortic Regurgitation

The ACC/AATS/SCAI/STS expert consensus explicitly excludes severe aortic regurgitation (AR) from current TAVR indications. 1 This exclusion applies regardless of the patient's surgical risk profile—whether prohibitive, high, intermediate, or low risk. 1

The rationale for this exclusion is the absence of adequate clinical trial data, not proven harm. 1 The landmark PARTNER trials and subsequent studies that established TAVR's efficacy specifically enrolled patients with severe aortic stenosis (AS), not AR. 1 In fact, severe AR was an explicit exclusion criterion in these pivotal trials. 1

Why TAVR Was Developed for Stenosis, Not Regurgitation

TAVR devices were designed and tested for calcified, stenotic aortic valves where:

• The calcification provides structural support for valve anchoring 1
• The rigid annulus prevents valve migration 1
• Hemodynamic goals focus on reducing transvalvular gradients 1

In contrast, severe AR presents fundamentally different anatomic and hemodynamic challenges:

• Lack of calcification reduces anchoring stability 1
• Dilated annulus increases risk of paravalvular leak and valve migration 1
• The regurgitant lesion requires complete seal rather than gradient reduction 1

Clinical Pitfalls and Complications

Paravalvular regurgitation after TAVR is associated with adverse prognosis and increased mortality. 2 When TAVR is performed in the setting of pre-existing AR (rather than AS), the risk of significant paravalvular leak is substantially elevated due to the non-calcified, often dilated annulus. 2

Case reports document catastrophic early valve degeneration when TAVR is attempted for AR, including leaflet malposition and severe combined valvular and paravalvular regurgitation requiring surgical revision. 2 One documented mechanism involves a "Venturi effect" from paravalvular jets causing premature transcatheter valve failure. 2

Current Evidence Base

All major TAVR trials establishing efficacy and safety enrolled patients with:

• Severe symptomatic calcific AS (AVA ≤1.0 cm², mean gradient ≥40 mmHg, or peak velocity ≥4.0 m/s) 1
• Trileaflet valve anatomy 1
• Suitable annular dimensions (18-25 mm in early trials) 1
• Explicit exclusion of severe AR or MR 1

The PARTNER trial showed TAVR reduced mortality compared to medical therapy (43.3% vs 68% at 2 years) in prohibitive-risk AS patients, but this evidence cannot be extrapolated to AR. 1

Emerging Data and Future Directions

Recent literature acknowledges that dedicated devices to treat native AR are under investigation and have shown "encouraging short-term outcomes," but these remain investigational. 3 Standard TAVR platforms approved for AS are not recommended for AR outside of clinical trials. 1

Recommended Management Approach

For patients with severe symptomatic AR:

Surgical aortic valve replacement remains the standard of care for patients who are acceptable surgical candidates. 1

For prohibitive surgical risk patients with severe AR:

• Medical management with afterload reduction (ACE inhibitors, ARBs, dihydropyridine calcium channel blockers) is the current standard 1
• Consider enrollment in clinical trials investigating AR-specific transcatheter devices 3
• Multidisciplinary Heart Team evaluation is essential if considering any investigational transcatheter approach 1, 4

Do not attempt TAVR with AS-approved devices for isolated severe AR outside of clinical trials or investigational protocols. 1

Special Circumstance: LVAD Patients

Limited case series describe TAVR for severe AR in patients with left ventricular assist devices (LVAD), where surgical options are extremely limited. 5 This represents a unique population where TAVR may be considered as a salvage option, but it remains technically challenging with high risk of paravalvular leak and valve migration. 5 This should only be attempted at experienced centers with careful patient selection and oversizing strategies. 5