In vivo estimation of left ventricular wall volume in volume-overloaded canine hearts
Feneley, M.P.; Gaynor, J.W.; Maier, G.W.; Gall, S.A.; Kisslo, J.A.; Rankin, J.S.
American Journal of Physiology 255(6 Pt 2): H1399-H1404
1988
ISSN/ISBN: 0002-9513 PMID: 3202203 Document Number: 322236
Several geometric algorithms have been applied to estimate left ventricular wall volume (Vwall) from two-dimensional echocardiograms but have not been validated in eccentrically hypertrophied hearts. These algorithms can be fitted to the general formula: Vwall = k .cntdot. Ao .cntdot. Lo -k .cntdot. Ai .cntdot. Li, where Ao and Ai are the outer (epicardial) and inner (endocardial) short-axis areas, Lo and Li are the corresponding long-axis lengths, and k is a constant. The simplifying assumption that Lo and Li are equal yields Vwall = k .cntdot. Awall .cntdot. Lo, where Awall = Ao-Ai. In 20 unsedated dogs (10-30 kg), including 10 with aortic regurgitation of 1-18 wk duration, the relationship between actual Vwall (determined postmortem) and Awall .cntdot. Lo was not significantly different from the line of identity (Vwall = 1.01 Awall .cntdot. Lo + 0.5 ml, r = 0.98, SEE = 3.5 ml), indicating k was not significantly different from 1. There was no significant difference between predicted and actual Vwall over a range of 31-105 ml, and interobserver variability was 4.1%. The simple area-length product, AWall .cntdot. Lo, accurately predicts Vwall of both normal and volume-overloaded hypertrophied canine left ventricles and is thus suitable for serial observations of hypertrophic adaptation to volume overload.