Objectives: to evaluate B-type Natriuretic Peptide (BNP) serum levels for the assessment of left ventricular (LV) filling pressure in patients with asymptomatic aortic stenosis (AS).

Methods and Results: In 40 consecutive patients aged 72 years [61-79] with moderate to severe AS (Peak velocity, 4.1 m/s [3.8-4.6]; indexed valve area, 0.5 cm²/m² [0.4-0.6]; mean transaortic pressure gradient, 42 mm Hg [37-53]), BNP serum levels were compared to LV filling pressures assessed by the ratio between mitral E wave (Em, pulsed Doppler) and Mitral annular E wave (Ea, pulsed Tissue Doppler). All patients were asymptomatic, with normal LV systolic function (ejection fraction, 0.64 [0.59-0.69] and without renal failure (serum creatinine, 94 µ. mol/L [86-115] or other significant valve disease. In the whole group, there was a strong correlation between BNP levels and Em/Ea (r = 0.65, p < 0.0001). In patients with an Em/Ea ratio > 14 (n = 13), BNP levels were significantly higher (199 pg/ml [177-211]) as compared to patients with Em/Ea < 8 (n = 20; BNP, 42 pg/ml [28-56], p < 0.0001). A serum BNP level > 100 pg/ml was found in all patients with Em/Ea > 14, as compared to 5% of patients with an Em/Ea < 8 (p < 0.0001).

Conclusions: In patients with asymptomatic (mostly severe) AS and normal LV systolic function, there is a strong correlation between serum BNP levels and LV filling pressures assessed by the Em/Ea ratio. Further studies are needed to evaluate the prognostic value of these 2 parameters used in combination.