Circulation, Vol 80, 51-64, Copyright © 1989 by American Heart Association
G Hasenfuss, C Holubarsch, HW Heiss, T Meinertz, T Bonzel, U Wais, M Lehmann and H Just
Cardiotonic agents influence myocardial energy consumption by vasodilation,
which may reduce energy demand, and by inotropism, which may increase it.
To distinguish between the two effects, myocardial oxygen consumption must
be analyzed in relation to its hemodynamic determinants. The coupling of
myocardial oxygen consumption with its determinants was investigated in 22
patients with idiopathic dilated cardiomyopathy (NYHA Class II and III).
Predicted myocardial oxygen consumption by the pressure-work index, the
Bretschneider index, and the pressure-volume area correlated moderately
with measured myocardial oxygen consumption (r = 0.57, p less than 0.001; r
= 0.52, p less than 0.005; and r = 0.63, p less than 0.001). Multiple
regression analysis, including left ventricular peak systolic wall stress,
systolic stress- time integral, pressure-volume work, maximum rate of left
ventricular pressure rise, and mean velocity of circumferential fiber
shortening indicated that systolic stress-time integral is the major
determinant of myocardial oxygen consumption (r = 0.75, p less than 0.001)
in these patients. Enoximone, a phosphodiesterase inhibitor, has an
inotropic and a vasodilating effect. To investigate the inotropic portion
of the energy cost of this phosphodiesterase inhibitor, the influence of
enoximone on myocardial oxygen consumption and systolic stress-time
integral was compared with the effects of nitroprusside, which is a
vasodilator only. Nitroprusside (10 patients) and enoximone (12 patients)
reduced left ventricular systolic stress-time integral from 109 +/- 22 to
71 +/- 21 (p less than 0.005) and from 104 +/- 23 to 42 +/- 10 (p less than
0.001) 10(3) dynes.sec/cm2, respectively. Myocardial oxygen consumption
decreased from 159 +/- 44 to 112 +/- 23 (p less than 0.005) and from 134
+/- 28 to 109 +/- 21 (p less than 0.001) microliters/beat/100 g,
respectively. In both groups, there was a significant correlation between
the decrease in myocardial oxygen consumption and the decrease in systolic
stress-time integral. The slopes of the respective linear regression lines
were significantly different (1.27 for nitroprusside and 0.51 nl.cm2/100
g.dynes.sec for enoximone, p less than 0.05), indicating a smaller decrease
of myocardial oxygen consumption for a given decrease of stress-time
integral with enoximone. Applying the pressure-work index or the
pressure-volume area instead of systolic stress-time integral yielded
comparable results. Thus, vasodilation reduces myocardial oxygen
consumption in proportion to the reduction of stress-time integral. With
enoximone, the energy-saving effect of vasodilation is counteracted in part
by the increased energy d
ARTICLES
Myocardial energetics in patients with dilated cardiomyopathy. Influence of nitroprusside and enoximone
Department of Internal Medicine, University of Freiburg, Medical School, FRG.
This article has been cited by other articles:
 |
|
 |
|
  A. N. Mazzadi, X. Andre-Fouet, N. Costes, P. Croisille, D. Revel, and M. F. Janier Mechanisms leading to reversible mechanical dysfunction in severe CAD: alternatives to myocardial stunning Am J Physiol Heart Circ Physiol, December 1, 2006; 291(6): H2570 - H2582. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Yuda, V. Khoury, and T. H. Marwick Influence of wall stress and left ventricular geometry on the accuracy of dobutamine stress echocardiography J. Am. Coll. Cardiol., October 2, 2002; 40(7): 1311 - 1319. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. l S. Kim, H. Izawa, T. Sobue, H. Ishihara, F. Somura, T. Nishizawa, K. Nagata, M. Iwase, and M. Yokota Prognostic value of mechanical efficiency in ambulatory patients with idiopathic dilated cardiomyopathy in sinus rhythm J. Am. Coll. Cardiol., April 17, 2002; 39(8): 1264 - 1268. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. S. Nelson, R. D. Berger, B. J. Fetics, M. Talbot, J. C. Spinelli, J. M. Hare, and D. A. Kass Left Ventricular or Biventricular Pacing Improves Cardiac Function at Diminished Energy Cost in Patients With Dilated Cardiomyopathy and Left Bundle-Branch Block Circulation, December 19, 2000; 102(25): 3053 - 3059. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. S. Nelson, C. W. Curry, B. T. Wyman, A. Kramer, J. Declerck, M. Talbot, M. R. Douglas, R. D. Berger, E. R. McVeigh, and D. A. Kass Predictors of Systolic Augmentation From Left Ventricular Preexcitation in Patients With Dilated Cardiomyopathy and Intraventricular Conduction Delay Circulation, June 13, 2000; 101(23): 2703 - 2709. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Senzaki, T. Isoda, N. Paolocci, U. Ekelund, J. M. Hare, and D. A. Kass Improved Mechanoenergetics and Cardiac Rest and Reserve Function of In Vivo Failing Heart by Calcium Sensitizer EMD-57033 Circulation, March 7, 2000; 101(9): 1040 - 1048. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. J. Eichhorn and M. R. Bristow Medical Therapy Can Improve the Biological Properties of the Chronically Failing Heart: A New Era in the Treatment of Heart Failure Circulation, November 1, 1996; 94(9): 2285 - 2296. [Abstract] [Full Text]
|
|
|
|
 |
|
 S. Fazio, D. Sabatini, B. Capaldo, C. Vigorito, A. Giordano, R. Guida, F. Pardo, B. Biondi, and L. Sacca A Preliminary Study of Growth Hormone in the Treatment of Dilated Cardiomyopathy N. Engl. J. Med., March 28, 1996; 334(13): 809 - 814. [Abstract] [Full Text] [PDF]
|
|