Conclusions
Stunned myocardium generally has normal resting flow and most studies have documented normal flow reserve. “Vascular stunning” (reduced vasodilator capacity) can be produced by ischemia, but the duration required is longer than that required to produce mechanical stunning. The two phenomenon can therefore be dissociated and are essentially unrelated. Nevertheless, despite evidence of normal microvascular patency in stunned myocardium, there are observations consistent with the existence of microvascular foci of ischemia, possibly related to vascular spasm or constriction, and this may explain the finding that increased flow in stunned myocardium may partially, or even largely, reverse the mechanical dysfunction. The “microvascular spasm” hypothesis may explain a significant portion of the dysfunction of stunned myocardium and deserves further study.
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References
Hori M, Inoue M, Kitakaze M, Koretsune Y, Iwai K, Tamai J, Ito H, Kitabakate A, Sato T, Kamada T (1986) Role of adenosine in hyperemic response of coronary blood flow in microembolization. Amer J Physiol 250: H509-H518
Bolli R (1990) Mechanism of myocardial “stunning”. Circulation 82: 723–738
Nicklas JM, Gips S (1989) Decreased coronary flow reserve after transient myocardial ischemia in dogs. J Am Coll Cardiol 13: 195–199
Bolli R, Triana JF, Jeroudi MO (1990) Prolonged impairment of coronary vasodilation after reversible ischemia. Evidence for microvascular “stunning”. Circ Res 67: 332–343
Jeremy RW, Stahl L, Gillinov M, Litt M, Aversano TR, Becker LC (1989) Preservation of coronary flow reserve in stunned myocardium. Am J Physiol 256: H1301-H1310
Duncker DJ, McFalls EO, Krams R, Verdouw PD (1992) Pressure-maximal coronary flow relationship in regionally stunned porcine myocardium. Am J Physiol 262: H1744-H1751
McFalls EO, Duncker DJ, Krams R, Ward H, Gornick C, Verdouw PD (1991) Endothelium dependent vasodilatation following brief ischemia and reperfusion in anaesthetized swine. Cardiovasc Res 25: 659–665
Stahl LD, Weiss HR, Becker LC (1988) Myocardial oxygen consumption, oxygen supply/demand heterogeneity and microvascular patency in regionally stunned myocardium. Circulation 77: 865–872
Jeremy RW, Becker LC (1989) Neutrophil depletion does not prevent myocardial dysfunction after brief coronary occlusion. J Am Coll Cardiol 13: 1155–1163
Juneau CF, Ito BR, del Balzo U, Engler RL (1993) Severe neutrophil depletion by leucocyte filters or cytotoxic drug does not improve recovery of contractile function in stunned porcine myocardium. Cardiovasc Res 27: 720–727
Stahl LD, Aversano TR, Becker LC (1986) Selective enhancement of function of stunned myocardium by increased flow. Circulation 74: 843–851
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Becker, L.C. Is stunned myocardium ischemic on a microvascular level?. Basic Res Cardiol 90, 282–284 (1995). https://doi.org/10.1007/BF00797900
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DOI: https://doi.org/10.1007/BF00797900