Relation of global longitudinal strain to left ventricular geometry in aortic valve stenosis

Abstract

Background: In patients with aortic stenosis (AS), increased afterload induces changes in left ventricular (LV) geometry to preserve a normal ejection fraction (EF). Nevertheless, myocardial dysfunction may occur in spite of a normal EF. Global longitudinal strain (GLS) analysis can detect subtle contractile dysfunction at a pre-clinical stage. The aim of our study was to assess LV function deteriorations with GLS analysis and the association with geometric changes in patients with AS and normal EF.
Methods: Forty four patients with moderate to severe AS and 40 controls were enrolled. All patients underwent echocardiography, including two-dimensional strain imaging. The relative wall thickness and LV muscle mass measurements were performed with magnetic resonance imaging and patients were subdivided into four groups: Group 1 with normal LV, Group 2 with concentric remodeling, Group 3 with eccentric hypertrophy, and Group 4 with concentric hypertrophy.
Results: The total group of patients with AS showed a GLS of -15.3 ± 3.6% while the control group reached -18.9 ± 3.2% (p < 0.001). GLS was lower in the hypertrophy Groups 3 and 4 compared to Groups 1 and 2 (12.9 ± 3.4% vs 17.2 ± 2.5%, p < 0.05, respectively). Splitting the patients into Groups 1 to 4, the GLS was -17.2 ± 2.4%, -17.2 ± 2.7%, -12.4 ± 3.8% and -13.1 ± 3.3, respectively (p = 0.002).
Conclusions: In subjects with AS, lower GLS is related to LV hypertrophy, but not to the presence of concentric remodeling. Assessment of GLS can identify subtle contractile dysfunction independent of a preserved EF, and might be useful in identifying patients at high risk for the transition from compensatory to pathological remodeling. (Cardiol J 2011; 18, 2: 151-156)