Abstract 2077: Impact of Impaired Longitudinal Strain on Exercise Tolerance in Patients with Asymptomatic Aortic Valve Stenosis: a 2D Strain Study
Background: Longitudinal contraction (LC) as assessed by tissue Doppler velocities is commonly altered prior to radial contraction in the evolution of LV remodeling in patients with severe aortic stenosis (AS). However, the relationship of LC to exercise tolerance or to therapeutic decisions has not been established.
Objectives: We used 2D echocardiographic strain to examine values of components of deformation in the setting of severe AS, and to correlate these values to exercise tolerance and to patient management.
Methods: 50 asymptomatic patients with severe AS (area < 1 cm2) and 25 controls were studied with echocardiography, treadmill exercise and BNP levels. Conventional echo parameters as well as longitudinal, radial and circumferential deformation by 2D strain were measured at rest. During treadmill exercise, maximum tolerated workload, maximum heart rate, blood pressure, EKG ST changes were obtained.
Results: Despite similar ejection fraction, AS patients presented with a significantly lower global longitudinal strain (GLS) (−17±4% vs −21±2%, p<0.001) more pronounced in basal segments (BLS) (−12±4% vs −18±3%, p<0.001), but no difference in radial or circumferential strains compared to controls. With cut-off of −18% and −13%, GLS and BLS were predicted inadequate exercise response (low blood pressure increase, EKG changes, symptoms appearance) with a sensitivity and specificity of 69 and 75% (AUC 0.71) and 77 and 83% (AUC 0.80), respectively. BLS were correlated to the BNP level (r= 0.45, p<0.05).
Conclusion: In asymptomatic patients with severe aortic stenosis, impaired longitudinal contraction assessed by 2D strain is associated with abnormal exercise response and BNP level.