This Article 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 Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nozawa, T. Articles by Suga, H. Search for Related Content PubMed PubMed Citation Articles by Nozawa, T. Articles by Suga, H.

Circulation, Vol 77, 1116-1124, Copyright © 1988 by American Heart Association

ARTICLES

Efficiency of energy transfer from pressure-volume area to external mechanical work increases with contractile state and decreases with afterload in the left ventricle of the anesthetized closed-chest dog

T Nozawa, Y Yasumura, S Futaki, N Tanaka, M Uenishi and H Suga
Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Osaka, Japan.

We studied the effects of ventricular end-systolic elastance (Ees) and effective arterial elastance (Ea) on the efficiency of energy transfer from pressure-volume area (PVA) to external mechanical work (EW) in the left ventricle of anesthetized closed-chest dogs. PVA represents the total mechanical energy generated by ventricular contraction, which is an intermediate form of energy between oxygen consumption, the total energy input, and EW, the effective energy output. PVA and EW were determined from ventricular pressure and volume, which were continuously measured with a volumetric conductance catheter. Measurements of Ees were obtained by transiently increasing afterload by an inflation of a Fogarty catheter in the thoracic descending aorta. Ea was determined as the ratio of end-systolic pressure to stroke volume. The EW/PVA efficiency of a steady-state contraction increased from 55% to 64%, with a 58% increase in Ees after dobutamine. Ees, which was smaller than Ea before dobutamine, became nearly equal to Ea after dobutamine, maximizing EW for a given end-diastolic volume. EW/PVA efficiency decreased with an abrupt increase in afterload before and after dobutamine. The sensitivity of the decrease in the EW/PVA efficiency to an increase in end-systolic pressure was significantly less after than before dobutamine. We could account for all these changes in EW/PVA efficiency by the relative changes in Ees and Ea in the pressure-volume diagram.

This article has been cited by other articles:

				Y. Tanoue, T. Maeda, S. Oda, H. Baba, Y. Oishi, S. Tokunaga, A. Nakashima, and R. Tominaga Left ventricular performance in aortic valve replacement Interactive CardioVascular and Thoracic Surgery, August 1, 2009; 9(2): 255 - 259. [Abstract] [Full Text] [PDF]

				T. Hanke, M. Misfeld, M. Heringlake, J. J. Schreuder, U. K.H. Wiegand, and F. Eberhardt The effect of biventricular pacing on cardiac function after weaning from cardiopulmonary bypass in patients with reduced left ventricular function: A pressure-volume loop analysis J. Thorac. Cardiovasc. Surg., July 1, 2009; 138(1): 148 - 156. [Abstract] [Full Text] [PDF]

				E. Y. Davani, J. H. Boyd, D. R. Dorscheid, Y. Wang, A. Meredith, E. Chau, G. K. Singhera, and K. R. Walley Cardiac ICAM-1 mediates leukocyte-dependent decreased ventricular contractility in endotoxemic mice Cardiovasc Res, October 1, 2006; 72(1): 134 - 142. [Abstract] [Full Text] [PDF]

				S. A.F. Tulner, P. Steendijk, R. J.M. Klautz, J. J. Bax, M. J. Schalij, E. E. van der Wall, and R. A.E. Dion Surgical ventricular restoration in patients with ischemic dilated cardiomyopathy: Evaluation of systolic and diastolic ventricular function, wall stress, dyssynchrony, and mechanical efficiency by pressure-volume loops. J. Thorac. Cardiovasc. Surg., September 1, 2006; 132(3): 610 - 620. [Abstract] [Full Text] [PDF]

				P. Steendijk, S. A. Tulner, J. J. Bax, P. V. Oemrawsingh, G. B. Bleeker, L. van Erven, H. Putter, H. F. Verwey, E. E. van der Wall, and M. J. Schalij Hemodynamic Effects of Long-Term Cardiac Resynchronization Therapy: Analysis by Pressure-Volume Loops Circulation, March 14, 2006; 113(10): 1295 - 1304. [Abstract] [Full Text] [PDF]

				Y. Araki, A. Usui, O. Kawaguchi, S. Saito, M.-H. Song, T. Akita, and Y. Ueda Pressure-volume relationship in isolated working heart with crystalloid perfusate in swine and imaging the valve motion Eur. J. Cardiothorac. Surg., September 1, 2005; 28(3): 435 - 442. [Abstract] [Full Text] [PDF]

				S. Mohri, J. Shimizu, G. Iribe, H. Ito, T. Morita, H. Yamaguchi, S. Sano, F. Kajiya, and H. Suga Normal distribution of ventricular pressure-volume area of arrhythmic beats under atrial fibrillation in canine heart Am J Physiol Heart Circ Physiol, April 1, 2005; 288(4): H1740 - H1746. [Abstract] [Full Text] [PDF]

				Y. Tanoue, H. Kado, Y. Shiokawa, N. Fusazaki, and S. Ishikawa Midterm Ventricular Performance After Norwood Procedure With Right Ventricular-Pulmonary Artery Conduit Ann. Thorac. Surg., December 1, 2004; 78(6): 1965 - 1971. [Abstract] [Full Text] [PDF]

				Y. Tanoue, H. Kado, T. Maeda, Y. Shiokawa, N. Fusazaki, and S. Ishikawa Left ventricular performance of pulmonary atresia with intact ventricular septum after right heart bypass surgery J. Thorac. Cardiovasc. Surg., November 1, 2004; 128(5): 710 - 717. [Abstract] [Full Text] [PDF]

				P. Kolh, A. Ghuysen, V. Tchana-Sato, V. D'Orio, P. Gerard, P. Morimont, R. Limet, and B. Lambermont Effects of increased afterload on left ventricular performance and mechanical efficiency are not baroreflex-mediated Eur. J. Cardiothorac. Surg., December 1, 2003; 24(6): 912 - 919. [Abstract] [Full Text] [PDF]

				Y. Tanoue, H. Ando, F. Fukumura, M. Umesue, T. Uchida, K. Taniguchi, and J. Tanaka Ventricular energetics in endoventricular circular patch plasty for dyskinetic anterior left ventricular aneurysm Ann. Thorac. Surg., April 1, 2003; 75(4): 1205 - 1208. [Abstract] [Full Text] [PDF]

				Y. Tanoue, P. Herijgers, B. Meuris, E. Verbeken, V. Leunens, M. Lox, and W. Flameng Ischemic preconditioning reduces unloaded myocardial oxygen consumption in an in-vivo sheep model* Cardiovasc Res, August 15, 2002; 55(3): 633 - 641. [Abstract] [Full Text] [PDF]

				Y. Ochiai, S. Morita, Y. Tanoue, Y. Kawachi, R. Tominaga, and H. Yasui Effects of amrinone, a phosphodiesterase inhibitor, on right ventricular/arterial coupling immediately after cardiac operations J. Thorac. Cardiovasc. Surg., July 1, 1998; 116(1): 139 - 147. [Abstract] [Full Text]

				Y. Uozaki, A. Murakami, H. Asanoi, S. Ishizaka, and T. Misaki Effect of Assisted Circulation on Left Ventricular Performance in a Canine Model Ann. Thorac. Surg., March 1, 1998; 65(3): 663 - 666. [Abstract] [Full Text] [PDF]

				L. Aklog, F. Y. Chen, BrianJ. deGuzman, MichaelP. Murphy, WendelJ. Smith, RitaG. Laurence, RobertF. Appleyard, and L. H. Cohn Right Latissimus Dorsi Cardiomyoplasty Improves Left Ventricular Energetics Ann. Thorac. Surg., September 1, 1997; 64(3): 670 - 677. [Abstract] [Full Text]