Final Feigenbaum’s Echocardiography DIGITAL

Feigenbaum’s Echocardiography

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Feigenbaum’s Echocardiography

FIGURE 5.36. Graphic demonstration of normal geometry, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy. American Society of Echocardiography recommended thresholds for defining hypertrophy are as noted.

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relaxation time (IVRT). e myocardial performance index (MPI) essentially divides the total isovolumic times (IVCT + IVRT) by the ejection time. is index, referred to as the MPI or “Tei index,” com- bines features of both systolic and diastolic function and has been shown to correlate with outcome in ischemic and nonischemic dis- ease states. Normal MPI is less than 0.40 with progressively greater values implying progressively worse ventricular function. FIGURE 5.37. Color tissue Doppler M-mode echocardiograms recorded in a normal patient in the upper panel and in a patient with anteroseptal dyskinesis in the lower panel. Notice in the upper panel, the abrupt blue colorization timed with the QRS ( downward-pointing arrow ) of the ventricular septum as it moves posteriorly followed by an abrupt change to red colorization representing anterior motion at the end of systole ( upward-pointing arrow ). Notice in the posterior wall the red colorization representing anterior motion of the normally moving posterior wall ( double-headed arrow ). The lower panel was recorded in a patient with an anteroseptal infarct and septal dyskinesis. Notice the similar appearance of the posterior wall colorization with normal red coloring encoding in systole ( double-headed arrows ) but the similar red encoding for the ventricular septum representing dyskinesis. PW, posterior wall.

An additional form of hypertrophy is the physiologic hypertro- phy seen in highly trained athletes. In general, this is a physiologic adaptation in which there is a slight increase in both wall thick- ness and chamber dimension. Wall thickness more than 13 mm is unusual in physiologic hypertrophy. Because the hypertrophy is a physiologic adaptation to physical training, wall stress tends to be normal. Physiologic hypertrophy seen in athletes regresses relatively quickly aer cessation of vigorous training and, as such, can be dif- ferentiated from pathologic hypertrophy seen in hypertrophic car- diomyopathy if imaging is repeated aer a period of deconditioning. MISCELLANEOUS TECHNIQUES ere are a number of miscellaneous techniques for evaluating le ventricular regional or global function which have been developed over the years. Some remain valid for routine or selective use in a contemporary echocardiography laboratory, while others have only limited utility or are exclusively used for research purposes. Tissue Doppler Color M-Mode Using colorized Doppler tissue imaging an M-mode line can be directed through the ventricle and a color Doppler M-mode of tis- sue motion acquired (Fig. 5.37). is technique has shown utility in describing the timing of wall motion abnormalities. In the presence of a le bundle branch block, clear alternation in blue-red coloriza- tion of the septum is seen in patients with multiphasic septal motion related to conduction disturbances. Myocardial Performance Index A rapidly determined index of ventricular function has been derived by comparing the total systolic time from mitral valve closure to mitral valve opening with the systolic time involved in actual aortic ‰ow (ejection time). Figures 5.38 and 5.39 illustrate the calculation of this index. e total systolic time is deŽned as isovolumic contraction time (IVCT) ± ejection time + isovolumic FOR EVALUATION OF LEFT VENTRICULAR FUNCTION

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FIGURE 5.38. Schematic outlining calculation of the myocardial performance index (MPI). The myocardial performance index is the ratio of the sum of the isovolumic contraction and relaxation times (IVCT, IVRT) to ejection time (ET). It can be calculated by subtracting ET from total systolic time (TST) as noted in the two alternate formulas. Normal MPI is ≤ 0.40.

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