Usefulness of (123)I-BMIPP and (201)TlCl nuclide scintigraphy in evaluation of myocarditis in patients with polymyositis or dermatomyositis

To investigate the usefulness of (123)I-BMIPP/(201)TlCl scintigraphy for evaluating the presence of myocarditis in patients with polymyositis (PM) or dermatomyositis (DM). We performed a retrospective study of 26 patients diagnosed with new-onset active PM/DM who underwent (123)I-BMIPP/(201)TlCl scintigraphy between 01 April 2010 and 20 March 2015. We determined the (123)I-BMIPP/(201)TlCl ratio and grouped the patients according to presence or absence of a mismatch. We evaluated the relationship between mismatch and the laboratory and echocardiographic findings. Mismatch was found in 13 (50%) patients. There was no statistically significant difference in age, cardiac troponin T, myoglobin, myosin light chain, aldolase levels, E wave/A wave ratio, right ventricular systolic pressure between the mismatch and non-mismatch groups. Left ventricular end-diastolic and end-systolic dimensions were significantly greater in the mismatch group (45.0 vs 42.5 mm, P = < .01 and 29.5 mm vs 25.0 mm, P < .01). Left ventricular ejection fraction was significantly lower in the mismatch group (63.5% vs 71.5%, P = .04). Significant inverse correlation (r = −0.44, P = .03) was observed between left ventricular ejection fraction and mismatch ratio. The use of (123)I-BMIPP/ (201)TlCl scintigraphy may be considered for evaluating myocarditis in patients with PM/DM.