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) 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 PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Gerald D. Buckberg Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Buckberg, G. D. Articles by Mahajan, A. Search for Related Content PubMed PubMed Citation Articles by Buckberg, G. D. Articles by Mahajan, A. Related Collections Cardiac - physiology Cardiac - other

Eur J Cardiothorac Surg 2006;29:S145-S149
© 2006 Elsevier Science NL

Review

Cardiac motion and fiber shortening: the whole and its parts

^a Option on Bioengineering, California Institute of Technology, Pasadena, CA, United States
^b Department of Surgery, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, 62-258 CHS, Los Angeles, CA 90095, United States
^c Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
^d Department of Anesthesiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States

Received 17 February 2006; accepted 27 February 2006.

^_* Corresponding author. Address: Department of Surgery, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, 62-258 CHS, Los Angeles, CA 90095, USA. Tel.: +1 310 206 1 27; fax: +1 310 8255895. (Email: gbuckberg{at}mednet.ucla.edu).

Radionuclide ventriculography findings in 24 subjects show that the ventricular blood pool motion goes from base to apex, a finding that contradicts the expectation that an apex to base relationship should exist, because excitation proceeds from apex to base. This discrepancy reflects a difference between motion caused by whole heart transmural action, and regional activity that does not require global movement. Confirmation of the radionuclide ventriculography findings was made from sonomicrometer crystals, echocardiography, and MRI that demonstrated early basal motion. During excitation, only the endocardial muscle is stimulated by the electrical impulse, but transmural motion that is needed for the endocardial motion that is detected by radionuclide ventriculography. Differences between the isometric and ejection phases are described, and there is discussion of how these findings relate to the myocardial band. The reality of twisting and downward motion of the heart observed during ejection only happens following transmural activation, a motion that exists far beyond the QRS electrical signal on the ECG.

Key Words: Radionuclide ventriculography • Echocardiography • Sonomicrometer crystals • MRI • Helical myocardial ventricular band • Excitation–contraction coupling