Pathophysiology of Q waves in II, III, avF in systemic lupus erythematosus. Evaluation using cardiovascular magnetic resonance imaging.

OBJECTIVES

To investigate the pathophysiology of Q waves in II, III, avF in systemic lupus erythematosus (SLE) by cardiovascular magnetic resonance (CMR).

METHODS

Inflammation evaluation by CMR using T2, early (EGE) and late gadolinium enhanced images (LGE) was performed in 20 SLE patients with mild cardiac symptoms and Q in leads II, III, avF of ECG. Their results were compared with 20 SLE patients with the same symptoms and normal ECG.

RESULTS

In both groups, T2, EGE and left ventricular ejection fraction were normal. However, in 3/20 with Q in II, III, avF, CMR revealed lesions indicative of acute myocarditis. In the rest of them, CMR documented transmural LGE, due to past inferior myocardial infarction in 4/20 and epicardial LGE due to past myocarditis in 8/20 (4/8 in the inferior and 4/8 in the lateral wall of left ventricle). No LGE was found in 5/20 and the Q was attributed to the position of the heart. In 3/20 with normal ECG, CMR detected past myocarditis in 2/3 and myocardial infarction in 1/3. Coronary angiography assessed coronary artery disease in all SLE with evidence of myocardial infarction and normal coronaries in 9/10 patients with past myocarditis.

CONCLUSION

Q in II, III, avF in SLE may indicate myocardial infarction, acute or past inflammation or be a positional finding. The lack of Q does not exclude the possibility of infarction or inflammation. CMR is the best tool to reveal the pathophysiology of Q waves in SLE and guide treatment of heart involvement in these patients.