Predictors of acute myocardial infarct size in STEMI patients receiving thrombolytic therapy: A delayed contrast enhanced cardiac MRI study

IntroductionDelayed contrast enhanced Cardiac MRI has been accepted as a standard tool worldwide for determination of infarcted myocardium and viability. Infarct size as determined by cardiac MRI has important therapeutic and prognostic information.MethodsTwenty six STEMI patients who had received thrombolytic therapy were subjected to cardiac MRI assessment at 5–7 day of admission. Base line variables of the study population were compared with the acute infarct size as determined by the Cardiac MRI.ResultsThe mean acute infarct size in our study population was 27.2 ± 17.4% of LV. We found through univariate analysis that final infarct size was dependent on time to thrombolysis (p = 0.04), Status of Thrombolysis (p = 0.01), smoking status (p = 0.02), location of infarct (p < 0.00001), presence of microvascular obstruction (p = 0.01) and viability status (p = 0.0004). Thus, larger acute infarct size was seen in delayed time to thrombolysis, failed status of thrombolysis, smokers, anterior location of the infarct, presence of microvascular obstruction and non viable myocardial status.ConclusionInfarct size as determined by Cardiac MRI has been shown to carry important therapeutic and prognostic information. We have tried to evaluate predictors of acute infarct on cardiac MRI in STEMI patients during their initial hospital stay. Knowing the predictors of acute infarct size can help in early intervention and provide prognostic information for future cardiac events.