Comparison between visual grading and planimetric quantification of microvascular obstruction extent assessment in reperfused acute myocardial infarction

Objectives Current methods for infarct size and microvascular obstruction (MVO) quantification by cardiac magnetic resonance (CMR) imaging rely on planimetry. This method is time-consuming. We sought to evaluate a direct assessment of MVO severity based on visual evaluation and to compare it to a reference method. Methods CMR was performed in 112 consecutive patients after reperfused myocardial infarction. MVO was estimated by direct visual assessment based on a three-grade severity scale (MVO 1, mild; MVO 2, moderate; MVO 3, severe) on late gadolinium-enhancement (LGE). Results MVO was present in 69 patients (61.6 %). Quantitative MVO extent significantly increased accordingly to visual MVO grading ( p