Lege Artis Medicinae

[Pathophysiology of myocardial ischemia and reperfusion]

PAPP Zoltán1, ÉDES István1

JUNE 01, 2000

Lege Artis Medicinae - 2000;10(06)

[Complete and long lasting loss of coronary circulation results in myocardial cell death (ischemic necrosis). Short lasting ischemia (few minutes) is well tolerated and it may bring certain protection against recurrent ischemia (ischemic preconditioning). Contractile force promptly diminishes following the onset of ischemia and the changes in the intracellular ATP or Ca2+ concentration do not explain this phenomenon. With the progression of ischemia, myocardial relaxation ceases and hypertonic muscle activation appears (ischemic contracture). During myocardial reperfusion following short-term ischemia, arrhythmias often develop and pump function is regularly depressed transiently (myocardial stunning). Permanent reduction in coronary blood supply results in sustained ventricular dysfunction (hibernation). It has been established, that pathologic processes leading to ischemic injury are distinct from those of reperfusion injury. Cellular events are complicated (Ca2+-overload, free radical injuries, activation of proteolytic processes, energy loss, membrane damage, hypercontracture, etc.), and complete understanding of the background of ischemic/reperfusion disorders is still awaited. ]


  1. Debreceni Egyetem, Orvos- és Egészségtudományi Centrum, Orvostudományi Kar, Kardiológiai Klinika, Debrecen



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