Longitudinal Myocardial Function Assessed by Tissue Velocity, Strain, and Strain Rate Tissue Doppler Echocardiography in Patients With AL (Primary) Cardiac Amyloidosis

Abstract
Background— AL amyloidosis with heart failure is associated with decreased longitudinal myocardial contraction measured by pulsed tissue Doppler imaging. We sought to clarify whether new modalities of myocardial strain Doppler (change in length per unit length) or strain rate (the temporal derivative of strain) were more sensitive than tissue Doppler and could detect early regional myocardial dysfunction before the onset of congestive heart failure (CHF) in patients with AL (primary) amyloidosis.