Strain and strain rate echocardiography.

Strain and strain rate echocardiography is an emerging technique for assessing myocardial systolic and diastolic function. It is envisioned that this modality could change the quantitative assessment of regional wall motion and improve the accuracy and reproducibility of test readings. Myocardial strain and strain rate can detect inducible ischemia and at earlier stages than visual estimation of wall motion or wall thickening parameters. Changes in systolic strain rate and strain have potential to discriminate between different myocardial viability states. Measurement of diastolic rate of deformation can differentiate physiologic from pathologic hypertrophy, and restrictive from constrictive cardiomyopathy. This article reviews basic principles and current experimental and clinical applications of strain and strain rate echocardiography.