The UK TAVI trial is the largest TAVI vs SAVR non-industry funded trial (funded by National Institute for Health Research Health Technology Assessment Programme). It included ≥70 year old patients with severe symptomatic aortic stenosis and increased operative risk due

to comorbidity or age (>80 years old was enough to be considered as high risk). The primary outcome was all cause-mortality. Exclusion criteria were scarce which derived in higher external validity as compared to previous trials. Furthermore, being a governmental funded trial, all available or authorized TAVI technologies were included. Consideration for surgical risk was not based on risk scores but on decision of the multidisciplinary team. For example, ≥70 years old and diabetes (or impaired ventricular function, or impaired renal function) was considered of increased surgical risk. The final risk score profile of included patients was of low risk (STS of 2.6 for TAVI, 2.7 for SAVR). Therefore, according to current guidelines, the results from the UK TAVI trial corresponds to the group of ≥70 year old, low-intermediate risk patients. 

UK TAVI trial resulted in similar outcomes between TAVI and SAVR at one year in the following outcomes:

• Mortality
• Myocardial infarction
• Reintervention
• Renal replacement therapy
• Symptom and functional capacity
• Transprosthetic gradients

SAVR was found to have higher risk for

• Major bleeding 

TAVI was found to have higher risk for

• Stroke (p=0.07 using HR and 0.047 using OR)
• Permanent pacemaker implantation
• Vascular complications
• More than mild paravalvular leak (>40%)

Now let’s see what are the recommendations from the different cardiological/surgical societies regarding this group of patients: 

• ACC/AHA 2020 : “For symptomatic patients with severe AS who are >80 years of age or for younger patients with a life expectancy <10 years and no anatomic contraindication to transfemoral TAVI, transfemoral TAVI is recommended in preference to SAVR.” 

• ESC/EACTS 2021: “TAVI is recommended in older patients (≥75years), or in those who are high risk (STSPROM/EuroSCORE II >8%) or unsuitable for surgery”

Both guidelines recommend with a higher level of recommendation TAVI vs SAVR in elder patients. The current UK TAVI trial has shown the lack of evidence behind the recommendation for the choice of intervention based on age which has been used by ACC/AHA and ESC/EACTS. This trial has supported the view that in elder patients with low or intermediate risk both strategies render similar outcomes and therefore should have a same level of recommendation. Furthermore, UK TAVI has shown higher risk for secondary outcomes in the TAVI subgroup which have its most important impact in younger and low risk patients. 

Although UK TAVI has included patients since 2014, more than 45% of patients received SAPIEN 3 (current valve technology). 

Finally, the data from the UK TAVI trial supports SAVR in elder low-intermediate risk patients and goes in opposite direction to the unilateral support given by ACC/AHA and ESC/EACTS for TAVI in these patients. Its results reinforce the behavior Latin American countries need to follow considering the financial constraints of TAVI.