A physiological approach to drug therapy in dilated cardiomyopathy. Echo-Doppler evaluation of cardiac mechanics, myocardial energetics, and ventriculo-vascular coupling.
Cardiac ultrasound imaging can be used in conjunction with calibrated external pulse recordings to provide detailed information regarding cardiovascular hemodynamics.  This review establishes a physiological framework for the echo-Doppler assessment of cardiac mechanics, left ventricular energetics, and ventriculo-systemic vascular coupling in patients with dilated cardiomyopathy.  The section on cardiac mechanics concerns the evaluation of overall cardiac performance and its individual determinants.  Particular emphasis is placed upon the use of noninvasive methodology to identify the relative contributions of altered loading conditions and intrinsic myocardial contractility to cardiac performance.  The noninvasive evaluation of left ventricular energetics is based on the physiological premise that myocardial oxygen consumption is a function of three major determinants, i.e., heart rate, contractility, and the integral of left ventricular systolic load (or wall stress).  Following a brief discussion of the vascular properties that determine the relationship between pressure and flow in the systemic circulation, noninvasive methods for determination of systemic vascular resistance and arterial compliance are described.  At the end of each section, practical clinical applications of these techniques to the evaluation and management of patients with dilated cardiomyopathy are presented.
Department of Medicine, University of Chicago Medical Center, 60637.
R H
RH
Marcus
R M
RM
Lang
A
A
Neumann
K M
KM
Borow
D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D002316:Cardiotonic Agents / Q000494:pharmacology; D015150:Echocardiography, Doppler / Q000379:methods*; D006321:Heart / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology