Abstract 13410: Left Ventricular Strain Predicts Major Adverse Cardiac Events in Asymptomatic Aortic Stenosis
Purpose Aortic stenosis (AS) remains a challenging clinical entity characterised by adverse left ventricular (LV) remodelling and sudden cardiac death, even in previously asymptomatic patients. Our aim was to determine whether myocardial strain parameters could predict the need for valve surgery and major adverse clinical events (MACE).
Methods 96 consecutive asymptomatic patients (73 male) with moderate or severe AS and preserved cardiac function were prospectively enrolled and underwent CMR scanning at 1.5T. LV function, mass and the presence of late gadolinium enhancement (LGE) were analysed using standard protocols, and LGE was scored by two independent operators. LV strain was analysed using grid-tagged CMR images, from which torsion, circumferential (cc) and longitudinal (l0) strain were derived.
Results Patients were followed for an average of 1.3±0.7 yrs and 18 suffered a major adverse clinical event (MACE; 1 death, 11 valve replacements, 1 atrial fibrillation, 1 pacemaker insertion, and 4 unplanned hospitalisations with cardiac symptoms). Patients with MACE had impaired mid LV peak systolic cc strain (-14.8±3 vs. -17.9±3%, p< 0.001), impaired diastolic torsion rate (-25±10 vs. -34±15os-1, p=0.04), and mildly increased peak transvalvular velocities (3.5±0.7 vs. 3.0±0.6ms-1, p=0.006), compared to those without MACE.There were no significant differences in l0 strain (-11.5±3 vs. -12.0±3%, p=0.5); LGE (p=0.3), BNP levels (18.7±27 vs. 18±31pmol/L, p=0.9), LVEF (69±10 vs 70±9%, p=0.74) or LV mass index (90±23 vs. 83±22 gm-2, p=0.23). Multivariate logistic regression showed that peak systolic cc strain was the strongest predictor of MACE (p=0.009). Figure shows survival analysis based on cc strain.
Conclusions These findings provide the first reported evidence of impaired cc strain as a predictor of MACE in asymptomatic patients with AS. This may have implications for risk stratification and guiding medical and surgical interventions.
- © 2011 by American Heart Association, Inc.