Is TAVI superior to surgery in high-risk patients? Insight into the concept of individual risk assessment

The prevalence of aortic valve stenosis (AS) is growing in developed countries because its prevalence increases with age. A growing number of elderly patients are currently referred to specialized centres to be evaluated for potential therapeutic strategies. Indeed, two techniques are nowadays able to treat high-risk AS patients: TAVI and surgical replacement (AVR). It is the purpose of the present review to summarize current knowledge on safety and efficacy of AVR and TAVI in high-risk patients; to focus on some aspects of recently published guidelines; to emphasize the growing importance of pre-operative individual risk assessment, which is considered the real crucial point for patient selection and trial's comparisons. Indeed, it is worth of noting that currently adopted risk-scores do not show satisfactory performances. Accordingly, it becomes of utmost importance to investigate several baseline but still neglected patients' characteristics (e.g. frailty, functional status, co-morbid conditions, etc.), as well as their pathogenetic relationships with interventional results and follow-up prognosis. All these items are emphasized in the present review. Finally, we have tried to anticipate future scenarios in terms of both ongoing clinical trials and improvements of risk-scores.