TABLE 1.

Summary of key information provided by tissue Doppler imaging

Variable	Physiological meaning	Clinical use
Systolic annular velocity (Sa)	Sa is a more direct measure of myocardial systolic contractile function than ejection fraction alone. Sa ≥10 cm/s indicates normal contractile function, Sa <10 cm/s indicates impaired contractile function, while Sa <5 cm/s indicates severely impaired contractile function	While Sa is always depressed in the setting of abnormally depressed ejection fraction, a depressed Sa can reflect myocardial disease in the setting of normal ejection fraction (eg, hypertrophic cardiomyopathy)
Early diastolic annular velocity (Ea)	Ea has been correlated to the invasively measured time constant of relaxation (Tau), thus providing a measure of myocardial relaxation. An Ea ≥10 cm/s reflects normal myocardial relaxation, an Ea <10 cm/s reflects impaired myocardial relaxation and an Ea <5 cm/s reflects severely impaired myocardial relaxation	Ea distinguishes a normal transmitral filling pattern (normal relaxation with normal left ventricular filling pressures) from a pseudonormal pattern (impaired relaxation with elevated left ventricular filling pressures), because both of these are seen as transmitral early diastolic velocity > late diastolic velocity (E>A) on the transmitral filling profile
Transmitral early diastolic velocity/tissue Doppler Ea (E/Ea)	Dividing E by Ea results in a ratio (E/Ea) that reflects left ventricular filling pressure. It should be noted that in patients with completely normal hearts (ie, normal structure, function and tissue Doppler indexes), the E/Ea is not a reliable measure of left ventricular filling pressure	An E/Ea ≥10 indicates normal left ventricular filling pressures, while an E/Ea ≥15 indicates elevated left ventricular filling pressures. An E/Ea from 11 to 14 is a gray zone, in which case other variables are needed to determine whether left ventricular filling pressures are elevated (see Table 2)