Abstract 11004: Prediction of Clinical Outcome in Patients With Aortic Stenosis by Left Ventricular Mechanical Dispersion
Introduction: There is a need for new parameters to improve risk stratification and assess outcome in patients with aortic stenosis (AS). Left ventricular (LV) mechanical dispersion by strain echocardiography reflects heterogeneous myocardial contraction and is a novel marker of sudden cardiac death in structural and primary electrical heart disease. We hypothesized that mechanical dispersion provides valuable prognostic information in patients with AS, and that mechanical dispersion can be used as a clinical tool for risk stratification in these patients
Methods: We included 55 patients (56% women,75±9 years) with moderate to severe AS. Global longitudinal strain (GLS) was assessed by speckle tracking echocardiography from a 16 LV segments model. Mechanical dispersion was calculated as standard deviation of time from Q/R on ECG to peak strain in 16 LV segments.
Results: Average aortic valve area was 0.7±0.2 cm2. Most patients had LV septal hypertrophy (12±2 mm) and preserved LV ejection fraction (EF) (57±10%). Aortic valve replacement (AVR) was performed in 37 (67%) patients. During 38±14 months follow-up, 15(27%) patients died (no 30-day mortality after AVR). LV ejection fraction (EF) and GLS were similar in the survival and non-survival group (58±9% vs. 54±13%, p=0.16, and -17.0±3.4% vs. -16.7±4.0%, p=0.78, respectively). Mechanical dispersion was the only echocardiographic parameter that differed between survivors and non-survivors (56±18ms vs. 69±19ms, p=0.02). C-statistics for mechanical dispersion showed an AUC of 0.70 (0.55-0.86) and a value of > 67 ms indicated worse survival (log rank < 0.01) (Fig.1)
Conclusions: LV mechanical dispersion was significantly higher in the AS non-survivors. Increased mechanical dispersion may be an additional risk marker and could give valuable prognostic information in patients with AS and preserved LVEF.
Author Disclosures: L.G. Klaeboe: None.
- © 2015 by American Heart Association, Inc.