HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 291/2/H762    most recent 00081.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Popovic, Z. B. Articles by Thomas, J. D. Search for Related Content PubMed PubMed Citation Articles by Popovic, Z. B. Articles by Thomas, J. D.

Scaling of diastolic intraventricular pressure gradients is related to filling time duration

Zoran B. Popovi,¹ Kathryn E. Richards,¹ Neil L. Greenberg,¹ Aleksandr Rovner,¹ Jeannie Drinko,¹ Yuanna Cheng,¹ Marc S. Penn,¹ Kiyotaka Fukamachi,¹ Niladri Mal,¹ Benjamin D. Levine,² Mario J. Garcia,¹ and James D. Thomas¹

¹Cardiovascular Imaging Center, The Cleveland Clinic Foundation, Cleveland, Ohio; and ²Institute for Exercise and Environmental Medicine, Presbyterian Hospital and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas

Submitted 19 January 2006 ; accepted in final form 20 March 2006

In early diastole, pressure is lower in the apex than in the base of the left ventricle (LV). This early intraventricular pressure difference (IVPD) facilitates LV filling. We assessed how LV diastolic IVPD and intraventricular pressure gradient (IVPG), defined as IVPD divided by length, scale to the heart size and other physiological variables. We studied 10 mice, 10 rats, 5 rabbits, 12 dogs, and 21 humans by echocardiography. Color Doppler M-mode data were postprocessed to reconstruct IVPD and IVPG. Normalized LV filling time was calculated by dividing filling time by RR interval. The relationship between IVPD, IVPG, normalized LV filling time, and LV end-diastolic volume (or mass) as fit to the general scaling equation Y = kM, where M is LV heart size parameter, Y is a dependent variable, k is a constant, and is the power of the scaling exponent. LV mass varied from 0.049 to 194 g, whereas end-diastolic volume varied from 0.011 to 149 ml. The values relating normalized LV filling time with LV mass and end-diastolic volume were 0.091 (SD 0.011) and 0.083 (SD 0.009), respectively (P < 0.0001 vs. 0 for both). The values relating IVPD with LV mass and end-diastolic volume were similarly significant at 0.271 (SD 0.039) and 0.243 (SD 0.0361), respectively (P < 0.0001 vs. 0 for both). Finally, values relating IVPG with LV mass and end-diastolic volume were –0.118 (SD 0.013) and –0.104 (SD 0.011), respectively (P < 0.0001 vs. 0 for both). As a result, there was an inverse relationship between IVPG and normalized LV filling time (r = –0.65, P < 0.001). We conclude that IVPD decrease, while IVPG increase with decreasing animal size. High IVPG in small mammals may be an adaptive mechanism to short filling times.

hemodynamics; diastolic function; comparative physiology

This article has been cited by other articles:

				Z. B. Popovic, C. Benejam, J. Bian, N. Mal, J. Drinko, K. Lee, F. Forudi, R. Reeg, N. L. Greenberg, J. D. Thomas, et al. Speckle-tracking echocardiography correctly identifies segmental left ventricular dysfunction induced by scarring in a rat model of myocardial infarction Am J Physiol Heart Circ Physiol, June 1, 2007; 292(6): H2809 - H2816. [Abstract] [Full Text] [PDF]