|
|
||||||||
Departments of 1Cardiac Sciences, 2Physiology and Biophysics, and 3Civil Engineering; and 4Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
Submitted 18 January 2006 ; accepted in final form 1 June 2006
During pulmonary artery constriction (PAC), an experimental model of acute right ventricular (RV) pressure overload, the interventricular septum flattens and inverts. Finite element (FE) analysis has shown that the septum is subject to axial compression and bending when so deformed. This study examines the effects of acute PAC on the left ventricular (LV) free wall and the role the pericardium may play in these effects. In eight open-chest anesthetized dogs, LV, RV, aortic, and pericardial pressures were recorded under control conditions and with PAC. Model dimensions were derived from two-dimensional echocardiography minor-axis images of the heart. At control (pericardium closed), FE analysis showed that the septum was concave to the LV; stresses in the LV, RV, and septum were low; and the pericardium was subject to circumferential tension. With PAC, RV end-diastolic pressure exceeded LV pressure and the septum inverted. Compressive stresses developed circumferentially in the septum out to the RV insertion points, forming an arch-like pattern. Sharp bending occurred near the insertion points, accompanied by flattening of the LV free wall. With the pericardium open, the deformations and stresses were different. The RV became much larger, especially with PAC. With PAC, the arch-like circumferential stresses still developed in the septum, but their magnitudes were reduced, compared with the pericardium-closed case. There was no free wall inversion and flattening was less. From these FE results, the pericardium has a significant influence on the structural behavior of the septum and the LV and RV free walls. Furthermore, the deformation of the heart is dependent on whether the pericardium is open or closed.
ventricular function, right ventricular overload; finite element analysis
This article has been cited by other articles:
![]() |
P. S. Halvorsen, L. A. Fleischer, A. Espinoza, O. J. Elle, L. Hoff, H. Skulstad, T. Edvardsen, and E. Fosse Detection of myocardial ischaemia by epicardial accelerometers in the pig Br. J. Anaesth., January 1, 2009; 102(1): 29 - 37. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. S. Halvorsen, A. Espinoza, L. A. Fleischer, O. J. Elle, L. Hoff, R. Lundblad, H. Skulstad, T. Edvardsen, H. Ihlen, and E. Fosse Feasibility of a three-axis epicardial accelerometer in detecting myocardial ischemia in cardiac surgical patients. J. Thorac. Cardiovasc. Surg., December 1, 2008; 136(6): 1496 - 1502. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. P. Sengupta, V. K. Krishnamoorthy, W. P. Abhayaratna, J. Korinek, M. Belohlavek, T. M. Sundt III, K. Chandrasekaran, F. Mookadam, J. B. Seward, A. J. Tajik, et al. Disparate patterns of left ventricular mechanics differentiate constrictive pericarditis from restrictive cardiomyopathy. J. Am. Coll. Cardiol. Img., January 1, 2008; 1(1): 29 - 38. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Liu, W. Zhang, and G. S. Kassab Effects of myocardial constraint on the passive mechanical behaviors of the coronary vessel wall Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H514 - H523. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |