Causative role of oxyradicals in myocardial stunning: a proven hypothesis. A brief review of the evidence demonstrating a major role of reactive oxygen species in several forms of postischemic dysfunction.

Whether or not ROS are the actual initiator or a downstream mediator of stunning, the theory that they play a major causative role in this phenomenon is now a proven hypothesis. ROS play a prominent role in multiple forms of stunning. Furthermore, the role of ROS is prominent not only in open-chest models but also in conscious animal preparations. The major challenge for future studies will be to identify the specific molecular targets of ROS-mediated damage and to decipher the pathways whereby ROS and calcium interact in the genesis of myocardial stunning.