Circulation, Vol 79, 371-382, Copyright © 1989 by American Heart Association
JE Udelson, RO Cannon 3d, SL Bacharach, TF Rumble and RO Bonow
Impaired left ventricular relaxation and filling is an important
pathophysiologic mechanism in hypertrophic cardiomyopathy. To determine
whether isoproterenol, known to improve relaxation in isolated cardiac
muscle, could favorably modify this effect, we assessed simultaneous left
ventricular volume and regional systolic asynchrony (by radionuclide
angiography), left ventricular pressure (by micromanometer catheters), and
lactate metabolism in 12 patients with hypertrophic cardiomyopathy.
Pressure-volume relations were studied during atrial pacing stress to
induce myocardial ischemia and during isoproterenol infusion to similar
heart rates. Angina occurred in 10 patients with pacing and in 11 patients
during isoproterenol infusion; lactate consumption was reduced in nine
patients during isoproterenol compared with pacing, including five patients
who produced lactate with isoproterenol. During isoproterenol compared with
pacing, peak left ventricular pressure was higher (205 +/- 33 vs. 142 +/-
21 mm Hg, p less than 0.001), ejection fraction was higher (77 +/- 10% vs.
71 +/- 12%, p less than 0.02), and regional systolic nonuniformity was
diminished. Despite ischemia, these changes in load and nonuniformity
during isoproterenol were associated with enhanced diastolic function
compared with pacing tachycardia: isoproterenol reduced T 1/2, the half-
time of pressure decline after peak negative dP/dt (from 46 +/- 10 to 33
+/- 6 msec, p less than 0.001), shifted the diastolic pressure- volume
curve downward and rightward in 10 of 12 patients, and increased
end-diastolic volume (from 77 +/- 18% to 100 +/- 11% of control values, p
less than 0.001) with no change in end-diastolic pressure (19 +/- 7 to 19
+/- 5 mm Hg, p = NS). Thus, despite ischemia, isoproterenol improved left
ventricular relaxation and filling compared with tachycardia in the absence
of beta-adrenergic stimulation. Although isoproterenol is detrimental in
hypertrophic cardiomyopathy by provoking ischemia, these data suggest that
the adverse effects of ischemia on ventricular relaxation and
distensibility may be alleviated by beta-adrenergic stimulation, possibly
as a result of enhanced inactivation and restored load sensitivity.
ARTICLES
Beta-adrenergic stimulation with isoproterenol enhances left ventricular diastolic performance in hypertrophic cardiomyopathy despite potentiation of myocardial ischemia. Comparison to rapid atrial pacing
Cardiology Branch, National Heart, Lung, and Blood Institute, Bethesda, Md 20892.
This article has been cited by other articles:
![]() |
M. A. Fifer and G. J. Vlahakes Management of Symptoms in Hypertrophic Cardiomyopathy Circulation, January 22, 2008; 117(3): 429 - 439. [Full Text] [PDF] |
||||
![]() |
L. van Heerebeek, A. Borbely, H. W.M. Niessen, J. G.F. Bronzwaer, J. van der Velden, G. J.M. Stienen, W. A. Linke, G. J. Laarman, and W. J. Paulus Myocardial Structure and Function Differ in Systolic and Diastolic Heart Failure Circulation, April 25, 2006; 113(16): 1966 - 1973. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Fukuda, Y. Wu, P. Nair, and H. L. Granzier Phosphorylation of Titin Modulates Passive Stiffness of Cardiac Muscle in a Titin Isoform-dependent Manner J. Gen. Physiol., February 28, 2005; 125(3): 257 - 271. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. R. Zile and D. L. Brutsaert New Concepts in Diastolic Dysfunction and Diastolic Heart Failure: Part II: Causal Mechanisms and Treatment Circulation, March 26, 2002; 105(12): 1503 - 1508. [Full Text] [PDF] |
||||
![]() |
Y. Takeichi, M. Yokota, M. Iwase, H. Izawa, T. Nishizawa, R. Ishiki, F. Somura, K. Nagata, S. Isobe, and A. Noda Biphasic changes in left ventricular end-diastolic pressure during dynamic exercise in patients with nonobstructive hypertrophic cardiomyopathy J. Am. Coll. Cardiol., August 1, 2001; 38(2): 335 - 343. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Izawa, M. Yokota, Y. Takeichi, M. Inagaki, K. Nagata, M. Iwase, and T. Sobue Adrenergic Control of the Force-Frequency and Relaxation-Frequency Relations in Patients With Hypertrophic Cardiomyopathy Circulation, November 4, 1997; 96(9): 2959 - 2968. [Abstract] [Full Text] |
||||
![]() |
H. Takano and S. A. Glantz Left Ventricular Contractility Predicts How the End-Diastolic Pressure-Volume Relation Shifts During Pacing-Induced Ischemia in Dogs Circulation, May 1, 1995; 91(9): 2423 - 2434. [Abstract] [Full Text] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1989 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |