Intraoperative Doppler Tissue Imaging Is a Valuable Addition to Cardiac Anesthesiologists' Armamentarium: A Core Review

Endocardial motion and surface/volume changes during the cardiac cycle are echocardiographic methods for regional (analysis of wall motion) and global (fractional area change, stroke volume, and ejection fraction) evaluation of cardiac function. These conventional methods can be subjective, and/or time consuming and, depending upon circumstances, may divert the anesthesiologist's attention from intraoperative activities. Doppler tissue imaging (DTI) is a novel echocardiographic technique, which displays and measures systolic and diastolic velocity from a myocardial region. DTI is simple to perform and independent of adequate endocardial imaging. The numeric information (velocity or time intervals) is easily obtained and measured. Assessment of systolic and diastolic function on regional (detection of ischemia) as well as global level (ejection fraction, grading of diastolic dysfunction) and evaluation of filling pressure can be derived from DTI signals and used by any practicing cardiac anesthesiologist. This review describes the principles, imaging modalities, and clinical applications of DTI.