This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Lalani, A. V. Articles by Lee, S. J. Search for Related Content PubMed PubMed Citation Articles by Lalani, A. V. Articles by Lee, S. J.

Circulation, Vol 54, 738-743, Copyright © 1976 by American Heart Association

ARTICLES

Echocardiographic measurement of cardiac output using the mitral valve and aortic root echo

AV Lalani and SJ Lee

The current echo method for measuring cardiac output (CO) has various technical limitations and is based on the assumptions that the left ventricle is not dilated and that it contracts uniformly. We have taken a different approach to measuring CO by echo: CO = cross-sectional area of aortic root X left ventricular ejection time X mean aortic flow velocity X heart rate. Using the Fick method, 34 measurements of CO were made in patients with normal aortic and mitral valves, with simultaneous echo recordings from the aortic and mitral valves. The systolic closure slope of the anterior mitral valve leaflet was assumed to represent the mean aortic flow velocity. CO by Fick and the proposed echo method correlated well, both in patients with (r = 0.94) and those without (r = 0.87) asynergy and the overall correlation was strong (r = 0.90). Using the conventional echo and Fick methods, a much weaker association was found between the two measurements in those patients with asynergy (r = 0.44) as opposed to those without asynergy (r = 0.77).