Abstract
Reduced coronary reserve is one of the hallmarks of ventricular hypertrophy. Although this reduced coronary reserve may not affect baseline left ventricular (LV) function, it could be of greater importance during periods of stress such as occurs during exercise where increased metabolic demands induced by the stress may not be fully met by increases in coronary blood flow. The impaired subendocardial coronary reserve is caused not only by the hypertrophy but also by the hemodynamic changes, e.g., the LV subendocardial wall stress, which increases markedly upon exercise. In the severely hypertrophied heart during exercise there is impaired subendocardial wall function even after 10 beats, i.e., the first 3 s of exercise, at a time when LV pressures and stresses had not increased, and subendocardial perfusion was still preserved. During more severe exercise, subendocardial dysfunction persisted and was associated with reduced subendocardial perfusion. After β-adrenergic receptor blockade with propanolol, the most intense level of exercise was associated with lesser increases in systolic and diastolic LV wall stresses, heart rate, and LV dP/dt, and the endo/epi blood flow ratio, an index of adequacy of subendocardial perfusion, was no longer reduced below unity, and there were no decreases in subendocardial wall thickening. Thus, the subendocardial dysfunction occurred rapidly, before alterations in LV systolic or diastolic wall stress or an alteration in the endo/epi blood flow ratio. However, the subendocardial hypoperfusion and depression in subendocardial wall thickening observed during more severe exercise in dogs with LV hypertrophy was prevented by pretreatment with β-adrenergic receptor blockade. Therefore, myocardial perfusion dependent and independent mechanisms mediate regional myocardial dysfunction during exercise in the hypertrophied heart.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Alyono D, Anderson RW, Parrish DG, Dai XZ, Bache RJ (1986) Alterations of myocardial blood flow associated with experimental canine left ventricular hypertrophy secondary to valvular aortic stenosis. Circ Res 58: 47–57
Bache RJ, Alyono D, Sublett E, Dai XZ (1986) Myocardial blood flow in left ventricular hypertrophy developing in young and adult dogs. Am J Physiol 251: H949–H956
Bache RJ, Arentzen CE, Simon AB, Vrobel TR (1984) Abnormalities in myocardial perfusion during tachycardia in dogs with left ventricular hypertrophy: metabolic evidence for myocardial ischemia. Circulation 69: 409–417
Bache RJ, Dai X, Alyono D, Vrobel TR, Homans DC (1987) Myocardial blood flow during exercise in dogs with left ventricular hypertrophy produced by aortic banding and perinephritic hypertension. Circulation 76 (4): 835–842
Bache RJ, Vrobel TR, Arentzen CE, Ring WS (1981) Effect of maximal coronary vasodilation on transmural myocardial perfusion during tachycardia in dogs with left ventricular hypertrophy. Circ Res 49: 742–750
Braunwald E, Kloner RA (1982) The stunned myocardium: Prolonged, postischemic ventricular dysfunction. Circulation 66: 1146–1149
Cannon III RO, Rosing DR, Maron BJ et al. (1985) Myocardial ischemia in patients with hypertrophic cardiomyopathy: contribution of inadequate vasodilator reserve and elevated left ventricular filling pressures. Circulation 71: 234–243
Doty DB, Eastham CL, Hiratzka LF, Wright CB, Marcus ML (1982) Determination of coronary reserve in patients with supravalvular aortic stenosis. Circulation 66(Suppl I): I–186–I–192
Fujii AM, Gelpi RJ, Mirsky I, Vatner SF (1988) Systolic and diastolic dysfunction during atrial pacing in conscious dogs with left ventricular hypertrophy. Circ Res 62: 462–470
Heyndrickx GR, Millard RW, McRitchie RJ, Maroko PR, Vatner SF (1975) Regional myocardial functional and electrophysiological alterations after brief coronary artery occlusion in conscious dogs. J Clin Invest 56: 978–985
Hittinger L, Shannon R, Bishop SP, Gelpi R, Vatner SF (1989) Subendomyocardial exhaustion of blood flow reserve and increased fibrosis in conscious dogs with heart failure. Circ Res 65: 971–980
Hittinger L, Shannon RP, Kohin S, Lader AS, Manders WT, Patrick TA, Kelly P, Vatner SF (1989) Isoproterenol-induced alterations in myocardial blood flow, systolic and diastolic function in conscious dogs with heart failure. Circulation 80: 658–668
Hittinger L, Shannon RP, Kohin S, Manders WT, Kelly P, Vatner SF (1990) Exercise induced subendocardial dysfunction in dogs with left ventricular hypertrophy. Circ Res 66: 329–343
Hittinger L, Shen Y-T, Patrick TA, Hasebe N, Komamura K, Ihara T, Manders WT, Vatner SF (1992) Mechanisms of subendocardial dysfunction in response to exercise in dogs with left ventricular hypertrophy, Circ Res 71: 423–434
Holtz J, Restorff WV, Bard P, Bassenge E (1977) Transmural distribution of myocardial blood flow and of coronary reserve in canine left ventricular hypertrophy. Basic Res Cardiol 72: 286–292
Homans DC, Sublett E, Dai X-Z, Bache RJ (1986) Persistence of regional left ventricular dysfunction after exercise induced myocardial ischemia. J Clin Invest 77: 66–73
Marcus ML, Doty DB, Hiratzka LF, Wright CB, Eastham CL (1982) Decreased coronary reserve: a mechanism for angina pectoris in patients with aortic stenosis and normal coronary artery. N Engl J Med 307: 1362–1367
Marcus ML, Mueller TM, Eastham CH (1981) Effects of short and long-term left ventricular hypertrophy on coronary circulation. Am J Physiol 241: H358–H362
Murray PA, Vatner SF (1981) Abnormal coronary vascular response to exercise in dogs with severe right ventricular hypertrophy. J Clin Invest 67: 1314–1323
Murray PA, Vatner SF (1981) Reduction of maximal coronary vasodilator capacity in conscious dogs with severe right ventricular hypertrophy. Circ Res 48: 25–33
O’Keefe DD, Hoffman JIE, Cheitlin R, O’Neill MJ, Allard JR, Shapkin E (1978) Coronary blood flow in experimental canine left ventricular hypertrophy. Circ Res 43: 43–51
Perreault CL, Shannon RP, Shen Y-T, Hasebe N, Vatner SF, Morgan JP (1992) Excitation-contraction coupling in dogs with compensated hypertrophy. Circulation 86 (Suppl I): I–825, 1992 (Abstract)
Rembert JC, Kleinman LH, Fedor JM, Wechsler AS, Greenfield JC Jr (1978) Myocardial blood flow in concentric left ventricular hypertrophy. J Clin Invest 62: 379–386
Thaulow E, Guth BD, Heusch G, Gilpin E, Schulz R, Kroeger K, Ross J Jr (1989) Characteristics of regional myocardial stunning after exercise in dogs with chronic coronary stenosis. Am J Physiol 257 (Heart Circ Physiol 26): H113–H119
Vatner DE, Vatner SF, Fuji AM, Homey CJ (1985) Loss of high affinity cardiac ß- adrenergic receptors in dogs with heart failure. J Clin Invest 76: 2259–2264
Vatner SF, Hittinger L (1993) Coronary vascular mechanisms involved in decompensation from hypertrophy to heart failure. J Am Coll Cardiol, in press
Vatner SF, Shannon R, Hittinger L (1990) Reduced subendocardial coronary reserve, a potential mechanism for impaired diastolic function in the hypertrophied and failing heart. Circulation 81(Suppl m):III–8–III–14
Vrobel TR, Ring WS, Anderson RW, Emery RW, Bache RJ (1980) Effect of heart rate on myocardial blood flow in dogs with left ventricular hypertrophy. Am J Physiol 239: H621–H627
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1993 Dr. Dietrich Steinkopff Verlag GmbH & Co. KG, Darmstadt
About this chapter
Cite this chapter
Vatner, S.F., Hittinger, L. (1993). Myocardial perfusion dependent and independent mechanisms of regional myocardial dysfunction in hypertrophy. In: Grobecker, H., Heusch, G., Strauer, B.E. (eds) Angiotensin and the Heart. Steinkopff. https://doi.org/10.1007/978-3-642-72497-8_6
Download citation
DOI: https://doi.org/10.1007/978-3-642-72497-8_6
Publisher Name: Steinkopff
Print ISBN: 978-3-7985-0936-8
Online ISBN: 978-3-642-72497-8
eBook Packages: Springer Book Archive