Re-defining care and reasoning in ST-elevation myocardial infarction by shifting focus to myocardial stunning

Purpose:Acute ischemic heart failure (AIHF) is a common life-threatening acute cardiovascular condition. Cardiac dysfunction in AIHF often involve myocardial tissue that is not irreparably injured.

This phenomenon is termed myocardial stunning (MS) and is defined as ‘temporary mechanical dysfunction, with the absence of irreversible histological damage’.

MS is seen in other conditions, such as the takotsubo syndrome (TS), which have better prognosis than AIHF despite more pronounced MS.

Our overarching aim is to understand how the mechanisms behind ischemic MS in AIHF can be manipulated to optimize cardiovascular function and survival.Methods:We will use mediation analysis to test the hypothesis is that women, who are more likely to develop AIHF than men despite developing similar infarct size, are predisposed for MS.We will prospectively compare cardiac function and hemodynamics in patients with AIHF versus TS.We will conduct a prospective nationwide multi-center randomized registry trial (RRCT) to test whether administration of the endogenous substance adenosine (vs saline) in AIHF improves recovery of MS and prognosis.We will test if induction of ‘TS-like MS’ in the setting of experimental AIHF reduces myocardial infarct size and improves cardiovascular function in a rat model of AIHF.Importance:Our research can provide valuable new insight into the mechanisms behind MS in AIHF, which may lead to better measures to improve cardiac function and patient prognosis in AIHF.