Prognostic Value of a Comprehensive Cardiac Magnetic Resonance Assessment Soon After a First ST-Segment Elevation Myocardial Infarction

OBJECTIVES: To evaluate the prognostic value of a comprehensive cardiac magnetic resonance (CMR) assessment soon after a first ST-segment elevation myocardial infarction (STEMI). Background: CMR allows for a simultaneous assessment of wall motion abnormalities (WMA), WMA with low-dose dobutamine (WMA-dobutamine), microvascular obstruction, and transmural necrosis. This approach has been proven to be useful to predict late systolic recovery soon after STEMI. Its prognostic value and the relative prognostic weight of these indexes are not well-defined.

METHODS: We studied 214 consecutive patients with a first STEMI treated with thrombolytic therapy or primary angioplasty discharged from hospital. In the first week (7 +/- 1 day after infarction), with CMR we determined the extent (number of segments) of WMA, WMA-dobutamine, microvascular obstruction, and transmural necrosis.

RESULTS: During a median follow-up of 553 days, 21 major adverse cardiac events (MACE) including 4 cardiac deaths, 6 nonfatal myocardial infarctions, and 11 readmissions for heart failure were documented. The MACE was associated with a larger extent of WMA (8 +/- 4 segments vs. 5 +/- 3 segments, p < 0.001), WMA-dobutamine (6 +/- 4 segments vs. 4 +/- 3 segments, p = 0.004), microvascular obstruction (3 +/- 3 segments vs. 1 +/- 2 segments p <0.001), and transmural necrosis (7 +/- 3 segments vs. 3 +/- 3 segments, p < 0.001). In a complete multivariate analysis that included baseline characteristics, electrocardiogram, biomarkers, angiography, ejection fraction, left ventricular volumes, and all CMR indexes, WMA/segment (hazard ratio: 1.29 [95% confidence interval: 1.11 to 1.49], p = 0.001) and the extent of transmural necrosis/segment (hazard ratio: 1.30 [95% confidence interval: 1.12 to 1.51], p < 0.001) were the only independent prognostic variables.

CONCLUSIONS: A comprehensive CMR assessment is useful for stratifying risk soon after STEMI, but only the extent of systolic dysfunction and of transmural necrosis provide independent prognostic information.

PMID: 19608133

Posted in Magnetic Resonance Imaging and tagged , , .

One Comment

  1. Well designed and very interesting study of a current topic.
    I found interesting that the strong prognostic information provided by microvascular obstruction was overcome by the extent of transmural necrosis when compared as independent prognostic determinants for MACE in this group of patients. However, when compared head-to-head (table 3), patients with MVO had a threefold incidence of MACE. I think that it would be interesting to compare the incidence of MACE in patients without or with MVO when there is than 50% of mural necrosis? Would that even the results? Thoughts?

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