Detection and Characteristics of Microvascular Obstruction in Reperfused Acute Myocardial Infarction using an Optimized Protocol for Contrast-Enhanced Cardiovascular Magnetic Resonance Imaging

OBJECTIVES: Several cardiovascular magnetic resonance imaging (CMR) techniques are used to detect microvascular obstruction (MVO) after acute myocardial infarction (AMI).

METHODS: To determine the prevalence of MVO and gain more insight into the dynamic changes in appearance of MVO, we studied 84 consecutive patients with a reperfused AMI on average 5 and 104 days after admission, using an optimised single breath-hold 3D inversion recovery gradient echo pulse sequence (IR-GRE) protocol.

RESULTS: Early MVO (2 min post-contrast) was detected in 53 patients (63%) and late MVO (10 min post-contrast) in 45 patients (54%; p = 0.008). The extent of MVO decreased from early to late imaging (4.3 +/- 3.2% vs. 1.8 +/- 1.8%, p < 0.001) and showed a heterogeneous pattern. At baseline, patients without MVO (early and late) had a higher left ventricular ejection fraction (LVEF) than patients with persistent late MVO (56 +/- 7% vs. 48 +/- 7%, p < 0.001) and LVEF was intermediate in patients with early MVO but late MVO disappearance (54 +/- 6%). During follow-up, LVEF improved in all three subgroups but remained intermediate in patients with late MVO disappearance.

CONCLUSIONS: This optimised single breath-hold 3D IR-GRE technique for imaging MVO early and late after contrast administration is fast, accurate and allows detection of patients with intermediate remodelling at follow-up. Marlon Humphrey Jersey

PMID: 19588152

Posted in Magnetic Resonance Imaging and tagged , , , .

One Comment

  1. The presence and amount of MVO has been associated with LV remodeling after an AMI. A referenced above demonstrated that 10 min delayed enhancement underestimates MVO when compared to FP sequences.

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