Reperfusion injury overview
|
Reperfusion injury Microchapters |
|
Treatment |
|---|
|
Reperfusion injury overview On the Web |
|
American Roentgen Ray Society Images of Reperfusion injury overview |
|
Risk calculators and risk factors for Reperfusion injury overview |
Editors-In-Chief: Anjan K. Chakrabarti, M.D. [1]; C. Michael Gibson, M.S., M.D. [2]; Associate Editors-In-Chief: Kashish Goel, M.D.
Overview
The introduction and wide application of reperfusion strategies in patients with STEMI has significantly reduced the mortality rate over last decade. Despite this, the rate of 30-day mortality remains high and about 25% of the patients develop heart failure. One of the mechanisms responsible for this is Reperfusion injury. Reperfusion injury refers to myocardial cell death secondary to restoration of blood flow to the ischemic myocardium. The absence of oxygen and nutrients from blood creates a condition in which the restoration of circulation results in inflammation and oxidative damage through the induction of oxidative stress rather than restoration of normal function. Few of the animal studies show that reperfusion injury may be responsible for approximately 50% of the final infarct size in STEMI patients[1]. Recent advances in understanding of the pathophysiologic process behind reperfusion injury and treatment targets have provided opportunities to reduce mortality.
Risk Factors
Risk factors for reperfusion injury include hypertension with left ventricular hypertrophy, congestive heart failure, increased age, diabetes, and hyperlipidemia.
Natural History, Complications and Prognosis
Reperfusion injury may be responsible for about 50% of the total infarct size after an acute myocardial infarction as well as myocardial stunning, congestive heart failure and reperfusion arrhythmias such as ventricular arrhythmias.[1]
Medical Therapy
While many pharmacotherapies are successful in limiting reperfusion injury in animal studies or ex-vivo, the majority have failed to improve clinical outcomes in randomized clinical trials in patients. Strategies may have failed as a result of targeting the wrong mechanism, because an inadequate dose was studied, because patients with insufficient potential for benefit were studied, and because the drug was administered too late (after reperfusion had already occurred).