Quantitative Methods for Analyzing Regional Systolic Function with Two‐Dimensional Echocardiography

Abstract

Abnormalities of regional systolic function are important complications of acute or chronic coronary artery disease. The extent and severity of these abnormalities are powerful predictors of subsequent clinical course.'-3 By virtue of its noninvasive nature, safety, portability, and ease of repetition, two-dimensional echocardiography (2DE) is, in theory, an ideal technique for studying systolic function following acute MI. Several studies have confirmed that qualitative analysis of 2D echocardiograms can identify regional contraction abn~rmalitiesl-~ and when used in a semiquantitative manner by experienced observers, provides important short-term prognostic information in patients with acute MI.'-396 In those surviving the acute phase of the infarction, predischarge semiquantitative 2DE predicts oneto two-year outcomes as Division of the LV into standardized segments," standard nomenclature for degree of asynergy," and other conventions promote a unified approach and allow interstudy comparisons. In general, when newer 2DE equipment is used, reproducibility of qualitative review of echocardiograms for identifying regional wall motion abnormalities (RWMA)'r5v6 compares favorably with previously reported results with qualitative angiography.'2*13 But qualitative and semiquantitative wall motion analyses are inferior to quantitative methods because of poorer reproducibility of results even when trained observers are used.".'3 Identifying diography. N Engl J Med 300:57, 1979. Armstrong WF, Conley MJ, Dillon JC, et al: Systolic expansion of infarcted myocardium explains the overestimation of infarct size by wall motion analysis. J A m Coll Cardiol 2513, 1984. Force T, Kemper AJ, Perkins L, et al: Overestimation of infarct size by quantitative two-dimensional echocardiography-the role of tethering and of analytic procedures. Circulation 73:(in press).

Perfusion and Function in the Normal and Abnormal Heart

“…Estimates of regional contraction can also be confounded by rotational and translational motion during systole which is unrelated to contraction. Approaches for dealing with noncontractile motion include the centerline approach developed by Sheehan and colleagues [80] and floating-and fixed-axis analyses discussed by Force and Parisi [81]. Finally, in slice-based approaches, efforts to image the same portion of myocardium at end-systole and end-diastole are complicated by baseto-apex shortening and/or translational movement during contraction.…”

Quantitative Echoca rdiograpy Part III

“…~-' ~ Several groups have shown that M-mode measurements are not as accurate as 2D for derivation of LV mass, particularly in distorted or asymmetric " ID="I4.65.4">hearts. '°-" It should be noted that measurements for wall thickness are small in value (i.e., [9][10][11][12][13][14] mm), and observer errors and the M-mode cursor orientation to the LV minor axis must be considered. Because and cpicardial arca (B).…”