Table 1

Recommendations for Intervention in patients with severe AS (ESC/EACTS guidelines 2017)

Symptomatic severe AS (surgical AVR or TAVI)	Class	Level
Indicated in severe high gradient AS (AV Vmax >4 m/s or mean gradient >40 mm Hg).	I	B
Indicated in patients with low-flow low-gradient severe AS with reduced ejection fraction and evidence of contractile reserve excluding pseudosevere AS.	I	C
Should be considered in patients with low-flow low-gradient severe AS with preserved ejection fraction after careful confirmation of severe AS.	IIa	C
Should be considered in patients with low-flow low-gradient severe AS with reduced ejection fraction without evidence of contractile reserve especially where CT calcium scoring confirms severe AS.	IIa	C
Should NOT be performed in patients with severe comorbidities where the intervention is unlikely to improve quality of life or survival.	III	C
Asymptomatic severe AS (surgical AVR only)
Indicated in patients with severe AS and left ventricular systolic dysfunction (LVEF <50%) not due to another cause.	I	C
Indicated in patients with abnormal exercise test showing symptoms on exercise clearly related to AS.	I	C
Should be considered in patients with abnormal exercise test showing a decrease in blood pressure below baseline.	IIa	C
Should be considered if the surgical risk is low and one of the following abnormalities is present: Very severe AS (AV Vmax >5.5 m/s). Severe valve calcification with a rate of progression ≥0.3 m/s/year. Markedly elevated BNP (>3-fold above age-corrected and sex-corrected normal range) confirmed by repeated measurements without other explanations. Severe pulmonary hypertension (systolic pulmonary artery pressure >60 mm Hg at rest confirmed by invasive measurement) without other explanation.	IIa	C

AS, aortic stenosis; AV, aortic valve; BNP, B-type natriuretic peptide; LVEF, left ventricular ejection fraction; TAVI, transcatheter aortic valve implantation.