Dynamic Changes in ST Segment Resolution After Myocardial Infarction and the Association with Microvascular Injury on Cardiac Magnetic Resonance Imaging

Incidence and Significance of Spontaneous ST Segment Re-elevation After Reperfused Anterior Acute Myocardial Infarction ― Relationship With Infarct Size, Adverse Remodeling, and Events at 1 Year―

“…The apparent discrepancy with the results of the present study could be explained by differences in study populations and the significantly smaller sample size in the study of Weaver et al, 10 with potential selection bias limitations. The population in the present study was more homogeneous because we only enrolled patients with anterior STEMI.…”

“…There are few data regarding the significance of ST segment reelevation after reperfusion, with most data coming from small clinical studies that were performed before the PPCI reperfusion era. [10][11][12][13][14] In these small studies, the results are discordant, suggesting either increased severity in myocardial injury, 10 increased infarct size and poorer LV functional outcomes, 11,12 subclinical pericarditis, 13 or no significant effect on LV functional outcomes. 14 Moreover, there have been no studies examining the relationship between ST segment re-elevation and clinical outcomes.…”

Intramyocardial haemorrhage after acute myocardial infarction

“…13 By contrast, patients with intramyocardial haemorrhage on T2-weighted cardiac MRI almost always exhibit microvascular obstruction on late gadolinium enhancement cardiac MRI. 13,89,[99][100][101][102] However, in a study that included human and porcine data, we found that when T2-weighted imaging is matched with late gadolinium enhancement cardiac MRI, the overall regions of intramyocardial haemorrhage and microvascular obstruction are strikingly similar and correspond to intramyocardial haemorrhage confirmed by histopathology. 12 The discrepancy between the two regions on different types of imaging might be explained by how the techniques show intramyocardial haemorrhage.…”

“…12 Because studies consistently demonstrate microvascular destruction in areas indicated as microvascular obstruction on late gadolinium enhancement cardiac MRI, microvascular injury might be a more appropriate term. 16,48,101,[103][104][105] Intramyocardial haemorrhage can, therefore, be taken as a sign of severe myocardial injury.…”

Prognostic significance and relationship of worst lead residual ST segment elevation with myocardial damage assessed by cardiovascular MRI in myocardial infarction

“…Numerous studies have convincingly demonstrated that the degree of ST segment elevation (STE) and its resolution (STR) strongly correlate with clinical outcomes 1. As an underlying mechanism, early normalisation of the ST segment may be related to an improvement in microvascular circulation2 3 and better myocardial perfusion,4 5 thereby leading to improved myocardial salvage6 as well as smaller infarcts 7…”