Abstract

Objective: To determine whether longitudinal left ventricular systolic function measured by Doppler tissue imaging (DTI) after exercise can identify early left ventricular dysfunction in asymptomatic patients with moderate–severe aortic stenosis.

Design: Case–control study.

Setting: Outpatient cardiology departments.

Patients: 20 patients with aortic stenosis, with or without equivocal symptoms, a peak aortic valve velocity ⩾3 m/s, and left ventricular ejection fraction >50% and 15 aged-matched normal controls.

Interventions: Echocardiogram performed at rest and immediately after treadmill exercise.

Main outcome measures: The peak systolic velocity of the lateral mitral annulus (S’) by DTI at rest and immediately after exercise, exercise capacity, exercise systolic blood pressure and the plasma level of B-type natriuretic peptide (BNP).

Results: For patients with aortic stenosis, mean (SD) aortic valve area was 0.95 (0.3) cm². At rest, S’ was similar for patients with aortic stenosis and controls, respectively (8.5 (1.5) vs 9.1 (1.8) cm/s, p = 0.15). However, after exercise, S’ (12.2 (3.2) vs 17 (2.8) cm/s, p<0.001) and the increase in S’ between rest and exercise (4 (3) vs 7.9 (1.5) cm/s, p<0.001) were lower in patients with aortic stenosis. In patients with aortic stenosis, a smaller increase in S’ after exercise was associated with lower exercise capacity (r = 0.5, p = 0.02), a smaller increase in exercise systolic blood pressure (r = 0.6, p = 0.005) and higher plasma level of BNP (r = 0.66, p = 0.002).

Conclusion: In asymptomatic patients with moderate–severe aortic stenosis a lower than normal increase in peak systolic mitral annular velocity after treadmill exercise is a marker of early left ventricular systolic dysfunction.