Lake Louise criteria is for the diagnosis of myocarditis on CMR

Lake Louise criteria is for the diagnosis of myocarditis on CMR

Lake Louise criteria are based on those for detection of myocardial edema, hyperemia and capillary leakage, necrosis and fibrosis. Myocardial early gadolinium enhancement suggests hyperemia and capillary leakage. Edema is indicated by an area of high intensity signal in T2 weighted images. It can be global in some cases. In the absence of late gadolinium enhancement which would indicate necrosis or fibrosis, edema is suggestive of potentially reversible myocardial injury. Global myocardial edema may be difficult to identify visually and needs software support which compares myocardial T2 weighted images with that of skeletal muscle. Similarly, hyperemia is also better appreciated by quantitative evaluation in comparison with skeletal muscle. A potential confounding factor is the presence of myositis along with myocarditis which reduces the value of comparative assessment. Two of the three criteria are required for the diagnosis of myocarditis in the setting of clinically suspected myocarditis.

Presence of left ventricular dysfunction and pericardial effusion are only additional supportive evidence for myocarditis, not primary diagnostic criteria.

Reference

1. Friedrich MG, Sechtem U, Schulz-Menger J, Holmvang G, Alakija P, Cooper LT, White JA, Abdel-Aty H, Gutberlet M, Prasad S, Aletras A, Laissy JP, Paterson I, Filipchuk NG, Kumar A, Pauschinger M, Liu P, International Consensus Group on Cardiovascular Magnetic Resonance in M. Cardiovascular magnetic resonance in myocarditis: A JACC white paper. J Am Coll Cardiol. 2009;53:1475-1487.