Diagnosis and management of patients with asymptomatic severe aortic stenosis

Table 1 Stages of aortic stenosis on the basis of American College of Cardiology/American Heart Association recommendations

		Hemodynamics	LV Function	AVA	Aortic valve
A	At risk of AS	Vmax < 2 m/s	Normal EF	-	Bicuspid, sclerosis
B	Progressive AS	Mild AS: Vmax < 2.0-2.9 m/s or mean ΔP < 20 mmHg Moderate AS: Vmax > 3.0-3.9 m/s or mean ΔP > 20-39 mmHg	Normal EF Early diastolic dysfunction	-	Mild to moderate calcification Reduction in motion Commissural fusion
C1	Asymptomatic severe AS	Vmax≥ 4 m/s or mean ΔP≥ 40 mmHg	Normal EF Diastolic dysfunction	≤ 1.0 cm2 or ≤ 0.6 cm2/m2	Severe calcification Severely reduced opening
C2	Asymptomatic severe AS with LV dysfunction	Vmax≥ 4 m/s or mean ΔP≥ 40 mmHg	EF < 50%	≤ 1.0 cm2 or ≤ 0.6 cm2/m2	Severe calcification Severely reduced opening
D1	Symptomatic severe high-gradient AS	Vmax≥ 4 m/s or mean ΔP≥ 40 mmHg	EF normal or decreased diastolic dysfunction	≤ 1.0 cm2 or ≤ 0.6 cm2/m2 Larger with AR/MR	Severe calcification Severely reduced opening
D2	Symptomatic severe low-flow/low-gradient AS with reduced LVEF	Vmax < 4 m/s or mean ΔP < 40 mmHg DOB stress shows Vmax > 4 m/s and AVA ≤ 1.0 cm2	EF < 50% diastolic dysfunction	≤ 1.0 cm2	Severe calcification Severely reduced opening
D3	Symptomatic severe low-gradient AS with normal LVEF or paradoxical low-flow severe AS	Vmax < 4 m/s or mean ΔP < 40 mmHg Stroke volume index < 35 mL/m2	EF ≥ 50% Small LV chamber Restrictive diastolic filling	≤ 1.0 cm2 or ≤ 0.6 cm2/m2	Severe calcification Severely reduced opening

Modified from Nishimura et al[16] with permission. ACC/AHA: American College of Cardiology/American Heart Association; AR: Aortic regurgitation; AS: Aortic stenosis; AVA: Aortic valve area; EF: Ejection fraction; LV: Left ventricular; MR: Mitral regurgitation; ΔP: Pressure gradient; V_max: Maximum aortic velocity.

Table 2 High-risk patients predicted from brain natriuretic peptide level

Source	BNP cut-off value	Results	Enrolled patients
Bergler-Klein et al[51]	BNP 130 pg/mL	BNP < 130 pg/mL (n = 25) had better symptom-free survival (P < 0.001)	Asymptomatic severe AS, EF ≥ 50% (n = 43)
Biner et al[33]	BNP 300 pg/mL	Combined use of BNP > 300 pg/mL and E/e’ > 15 predicted 1-yr mortality (hazard ratio = 2.59; 95%CI: 1.21-5.55, P = 0.014)	Severe AS, symptomatic and asymptomatic, any EF included (n = 79)
Berger-Klein et al[54]	BNP 550 pg/mL	BNP ≥ 550 pg/mL showed poorer survival both in medically and surgically treated groups	Indexed effective orifice area ≤ 0.6 cm2/m2 with low-flow/low-gradient AS; symptomatic and asymptomatic, with EF ≤ 40% (n = 69)
Clavel et al[52]	BNP ratio: Measured BNP/maximal-normal-BNP for age and sex	Higher BNP ratio showed worse mortality in asymptomatic patients with preserved EF (hazard ratio = 2.35; 95%CI: 1.57-3.56, P < 0.0001)	Total, moderate or severe AS, any EF (n = 1953) Asymptomatic, with EF > 50% (n = 565)

AS: Aortic stenosis; BNP: Brain natriuretic peptide; EF: Ejection fraction.