Spatial characterization of contracting cardiac myocytes by
computer assisted video-based image processing.
Wang, Zhongling, Rupak Mukherjee, Chan F. Lam, and Francis G. Spinale.
Division of Cardiothoracic Surgery, and Department of Biometry and
Epidemiology, Medical University of South Carolina, Charleston, SC
29425, USA
APStracts 2:0363H, 1995.
Time-dependent changes in the three-dimensional structure of the
cardiac myocyte during contraction, particularly with the development
of cardiac disease, remained unexplored. Accordingly, the goals of
the present study were threefold: first, to develop and validate a
computer assisted video-based image processing (CAVIP) system to
measure time-dependent changes in isolated myocyte geometry during
contraction, second, to use the CAVIP system to examine the spatial
characteristics of the myocyte during contraction in normal myocytes
and in myocytes following the development of dilated cardiomyopathy
(DCM), and third, to employ the CAVIP system to determine myocyte
volumes during contraction. The CAVIP system was based on a 80486
computer equipped with a high speed image acquisition board. Myocytes
were isolated from the left ventricles of 5 control pigs and 5 pigs
following the development of chronic tachycardia (pace: 240 bpm, 3
weeks) induced DCM. Isolated myocytes were stimulated and recorded
using a high-speed camera interfaced to a standard video recording
system. There was a significant linear relation between the indices
of time-dependent changes in myocyte length as measured by a
conventional video edge detector system and the CAVIP system
(r>0.96; p<0.01). Following this validation procedure, the
dynamic changes in myocyte width and profile area with DCM were
examined. Myocyte resting profile area was 33% larger in DCM myocytes
compared to controls. However, there was no difference in the rate of
area change with contraction between the two groups. The percentage
change in myocyte width and profile area at peak contraction were
significantly lower in the DCM group (43% and 46% respectively,
p<0.05). Therefore, the present study demonstrated that the
CAVIP system provided unique information on time-dependent changes in
myocyte geometry during contraction, particularly with the
development of cardiomyopathic disease.
Received 3 April 1995; accepted in final form 3 August 1995.
APS Manuscript Number H317-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 August 1995.