Transcatheter aortic valve implantation (TAVI) for people with severe aortic stenosis who are at low surgical risk (latest update May 2026)

1. The Council recognised that not all patients who are classed as low surgical risk are suitable for TAVI. The decision on whether TAVI is the best treatment option for each patient is made by a multidisciplinary team as part of the shared decision making process. This ensures that each patient is offered the most appropriate treatment for their individual circumstances.

2. The Council agreed that TAVI was clinically beneficial and offered an improved safety profile compared with SAVR for patients in the low surgical risk group. The Council also agreed that TAVI may lead to an improved procedure related experience for patients compared with SAVR, based on quality of life evidence and qualitative studies.

3. The Council discussed the significance of people who had TAVI being more likely to experience paravalvular leaks compared with SAVR. An invited clinical expert explained that it is difficult to compare rates of paravalvular leaks between the two interventions, and that only moderate or severe leaks were likely to affect patient outcomes. The Council noted that newer TAVI valves had a lower risk of paravalvular leaks.

4. The Council asked the clinical expert for insight into the relative length of hospital stay for patients after TAVI or SAVR. The expert stated that TAVI patients tend to leave hospital after no more than a day in a general ward or outpatient clinic, whereas SAVR patients may require 1–2 days in intensive care and remain on a post-surgical ward for 4–5 days.

5. The Council discussed the UK based evidence on the cost effectiveness of TAVI and how the cost of TAVI devices and improved patient survival after TAVI appeared to be a key driver of cost-effectiveness. The Council agreed that procurement decisions should be coordinated to ensure that Scotland achieves the best value when purchasing TAVI valves, taking into account the possibility of volume based rebates from device manufacturers. (Council consideration point updated in May 2026 to reflect the final publication of the NICE late stage assessment).

6. The Council highlighted that patients with symptomatic severe aortic stenosis who are at low surgical risk represent a much larger population than those currently eligible for TAVI in Scotland (inoperable or high surgical risk). The Council recognised that offering TAVI to low surgical risk patients would present challenges for the delivery of TAVI services across NHSScotland because of limited capacity. The Council was clear in their opinion that if capacity were to increase, then access to TAVI should be prioritised based on surgical risk, so that patients who have the fewest alternative treatment options are offered TAVI first.

7. Concerns were voiced by the Council that there appeared to be unequal access to TAVI depending on where people lived, both within Scotland and compared with other areas of the UK and Europe. A clinical expert informed the Council that the number of TAVI procedures per million population was expected to increase nationally, across all TAVI centres, to align with rates in NHS England. They also advised, specifically in relation to the potential unequal access to TAVI within Scotland, that the small number of people getting TAVI in some board areas could lead to exaggerated differences in TAVI procedures per million population. The Council agreed it was important that there was equal access to TAVI for all suitable patients living in Scotland.

8. The Council understood that patients who are categorised as low surgical risk tend to be younger and have a longer life expectancy than higher risk patients, and that life expectancy for this patient group could exceed the durability of TAVI valves. It was accepted that the results from the NOTION trial after 10 years follow up suggest this may not be an issue with newer TAVI valves

Clinical effectiveness and safety

1.  Six meta-analyses were selected for review based on their methodological quality, length of follow up, outcomes and primary study designs. 4-9 They included an overlapping set of five RCTs and eight observational studies reporting all-cause mortality after TAVI compared with SAVR in people with symptomatic severe aortic stenosis who are at low surgical risk.

o A Cochrane review of four RCTs (n=2,818) reported no statistically significant difference in all-cause mortality at 30 days follow up (relative risk (RR) 0.60, 95% confidence interval (CI) 0.33 to 1.44) or 1 year follow up (RR 0.70, 95% CI 0.44 to 1.11).

o A meta-analysis of three RCTs (n=2,748) found no statistically significant difference in all[1][1]cause mortality at 4–5 years follow up (odds ratio (OR) 0.94, 95% CI 0.65 to 1.37).8 One of the RCTs, the NOTION trial reported consistent findings at 8 and 10 years follow up.

o A time to event meta-analysis of three RCTs and five observational studies (n=5,444) found no statistically significant difference in all-cause mortality over the first 2 years of follow up (hazard ratio (HR) 1.08, 95% CI 0.89 to 1.31).9 Meta-analysis of the observational studies found a statistically significantly higher risk of all-cause mortality for the TAVI group compared with the SAVR group between 2 and 8 years follow up (HR 1.51, 95% CI 1.14 to 2.00, n=2,696). These longer term results should be interpreted with caution because observational studies have inherent biases compared with RCTs.

2.  Three recently published RCTs (UK TAVI, DEDICATE, NOTION-2) also concluded there were no statistically significant differences in all-cause mortality in comparisons of TAVI and SAVR at 1 year follow up.

3.  Four out of five RCTs that reported length of hospital stay found that patients who had a TAVI procedure needed to stay in hospital for significantly fewer days than patients who had SAVR. The only RCT that reported a longer hospital stay for TAVI patients (STACCATO) used a higher risk vascular access route for performing TAVI.

4.  A meta-analysis of studies in people at low or intermediate surgical risk (n=3,681 low risk patients) found a statistically significant improvement in quality of life for people who had a TAVI procedure compared with people who had SAVR at 30 days follow up. At 1 year follow up there was no statistically significant between group difference in quality of life scores

5.  The six meta-analyses reported that TAVI was associated with statistically significantly higher risks of new pacemaker implantation and paravalvular leaks. In the same meta-analyses, TAVI was associated with significantly lower risks of new onset atrial fibrillation, acute kidney injury and bleeding.

o A Cochrane review (n=2,748) demonstrated a statistically significantly higher risk of new permanent pacemaker implantation in the TAVI group compared with the SAVR group (HR 3.65, 95% CI 1.50 to 8.87).

o Two meta-analyses (n=2,611 and n=2,219) reported a seven- to nine-fold higher risk of paravalvular leaks in patients who had TAVI compared with patients who had SAVR. It was unclear whether the severity of these paravalvular leaks affected patient outcomes.

o The Cochrane review also found statistically significantly lower risks of new onset atrial fibrillation (HR 0.21, 95% CI 0.15 to 0.30), acute kidney injury (HR 0.30, 95% CI 0.16 to 0.58) and any bleeding event (HR 0.31, 95% CI 0.16 to 0.72) in the TAVI group compared with the SAVR group.

o Safety results were consistent over the long term (more than 1 year follow up), across more recent RCTs and in meta-analyses of observational studies.

Cost effectiveness

6.  A systematic review of six economic analyses comparing TAVI with SAVR in people with symptomatic severe aortic stenosis who are at low surgical risk, found that TAVI was dominant (more effective and less costly) in one study, cost effective in three studies and not cost effective in one study. The study that reported TAVI was not cost effective was based on older (2010 vs 2018) TAVI devices that may have a different effectiveness and cost profile.

7.  Nine primary economic evaluations compared TAVI (using the SAPIEN 3 valve) with SAVR.

o Seven analyses conducted in European countries using local health system cost data found the SAPIEN 3 TAVI valve to be dominant or cost effective (that is, below willingness to pay thresholds) compared with SAVR. The analyses used outcome data from the PARTNER 3 trial, combined with local costs. Results were stable across time horizons of up to 30 years. TAVI was not cost effective when the analyses were restricted to a time horizon of 5 years.

o Economic evaluations from the United States (US) and Japanese payer perspectives found that TAVI was dominant or cost effective compared with SAVR.

o Key drivers of cost effectiveness attributed to TAVI are greater survival benefit, fewer complications and lower long term management costs. Higher device and 1 year follow up costs for TAVI are offset by lower healthcare costs over a lifetime time horizon.

8.  In 2021, the National Institute for Health and Care Excellence (NICE) published an economic evaluation using data from RCTs and the UK TAVI registry. The NICE model found that TAVI was not cost effective compared with SAVR in people at low surgical risk over a 15-year time horizon.

o  The conflicting results of the NICE evaluation compared with other published economic evaluations can mainly be attributed to higher device procurement costs in the UK (£17,500) compared to other countries.

o   The NICE late stage assessment in 2025, concluded that the 2021 economic evaluation was limited by the reliance on data analysis from the UK TAVI registry which was highly uncertain and led to significant bias and uncertainty about the results of the economic model. If the analysis was updated with more recent data the cost effectiveness results may change. (Key point updated in May 2026 to reflect the final publication of the NICE late stage assessment).

9.  An economic analysis from the perspective of the UK NHS (2024) used 4-year follow up data from the Evolut Low Risk trial to compare TAVI using the Evolut self-expanding valve with SAVR.29 TAVI was cost effective at an assumed UK TAVI valve list price of £17,500 over a lifetime horizon.

o The improved cost effectiveness of TAVI in this analysis compared with the NICE evaluation can be attributed to the availability of longer follow up data from the Evolut Low Risk trial, which suggests improved survival and outcomes after TAVI that leads to a ten-fold increase in QALYs over a 15-year time horizon. Patient and social aspects

10.  This section describes patient and social aspects relating to TAVI among people who have symptomatic severe aortic stenosis regardless of their surgical risk because the literature rarely reports the level of surgical risk applicable to study participants.

11.  A retrospective cohort study (n=10,069) in NHS England found inequalities in access to aortic valve replacement procedures (TAVI or SAVR) for women, people living in more deprived areas and people of African or south Asian descent.

12.  A systematic review (n=353) explored patient experiences of having a TAVI procedure.

o Having an individualised care plan was important to patients because it helped mitigate any disappointment or frustration relating to outcomes after the procedure. When people felt their treatment goals had been met, they reported improved quality of life even when objective measures suggested minimal change in functional outcomes.

o Some patients experience persistent psychosocial and physical symptoms after their procedure, often because of pre-existing comorbidities. For many people this led to feelings of disappointment, isolation and vulnerability.

13.  A systematic review (n=1,096), a qualitative study (n=18) and a cross-sectional study (n=98) explored people’s reasons for undergoing treatment for aortic stenosis and factors influencing their decision. Patients were often motivated by a strong desire to regain some semblance of a normal life and to continue living independently. The published literature suggests this could be achieved more quickly after TAVI compared with SAVR

What were we asked to look at?

We were asked to review the evidence comparing TAVI with SAVR for the treatment of people with symptomatic severe aortic stenosis who are at low surgical risk.

Why is this important?

Aortic stenosis is the most common heart valve disease in adults in Europe.

The prevalence of aortic stenosis increases steeply with age and is expected to become more prevalent as the Scottish population gets older. Without intervention, people with symptomatic severe aortic stenosis have a poor prognosis, with an average life expectancy of 2–3 years and survival rates of 15–50% at 5 years after diagnosis.

For people with symptomatic severe aortic stenosis the two main treatment options are SAVR and TAVI. Data from randomised controlled trials (RCTs) in people with symptomatic severe aortic stenosis who are at high or intermediate surgical risk show that TAVI is either as good as or better than SAVR. Approximately 80% of people with symptomatic severe aortic stenosis who are suitable for SAVR are defined as low surgical risk. This review examines the evidence for TAVI compared with SAVR in the low surgical risk population