Speckle Tracking Echocardiography Identifies Impaired Longitudinal Strain as a Common Deficit in Various Cardiac Diseases

The use of speckle-tracking echocardiography(STE)is becoming an increasingly useful tool in the evaluation of myocardial disease.STE software can track the motion of the specular pattern created by the interference of ultrasound with the myofibers of the heart and provide a quantitative means to evaluate subtle changes in ventricular function that often occur before changes in ventricular ejection fraction are observed.STE is most often used to measure the change in shape(strain)of myocardial segments in the circumferential,radial,and longitudinal directions.In various diseases,including coronary artery disease,aortic stenosis,and mitral regurgitation,deficits in longitudinal strain appear to occur earlier than deficits in other measures of strain or in ejection fraction.Consideration of STE measures of left ventricular contraction has the potential to significantly affect clinical management and outcomes of ischemic and valvular heart disease given the ability to separate those with asymptomatic disease who may benefit from earlier interventions than current guidelines may suggest.