Assessment of inflammation in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a myocardial disease that predominantly affects the right ventricle (RV). Its hallmark feature is fibro-fatty replacement of RV myocardium. However, patchy inflammatory infiltrates in the RV are also consistently reported using autopsy and myocardial biopsy. Although the role of inflammation in ARVC/D is unresolved, the ability to assess inflammation non-invasively may aid in the diagnostic process. We aimed to establish whether cardiac inflammation can be assessed non-invasively in ARVC/D patients. In eight ARVC/D patients and nine controls (haematology/oncology patients), the level of inflammatory activation was assessed by measuring plasma levels of inflammatory cytokines. Regional myocardial inflammation was assessed with Ga-67 scintigraphy. ARVC/D patients had higher plasma levels than controls of the pro-inflammatory cytokines interleukin (IL)-1 beta (1.22 +/- 0.07 vs 0.08 +/- 0.01 pg/ml, p < 0.0001), IL-6 (3.16 +/- 0.44 vs 0.38 +/- 0.04 pg/ml, p < 0.0001) and tumour necrosis factor (TNF)-alpha (9.16 +/- 0.90 vs 0.40 +/- 0.06 pg/ml, p < 0.0001), while levels of the anti-inflammatory cytokine IL-10 were not significantly different (1.36 +/- 0.15 vs 1.20 +/- 0.30 pg/ml, p = 0.74). Ga-67 uptake in the RV was higher in ARVC/D patients than in controls. In ARVC/D patients, Ga-67 uptake in the RV wall was higher than in the interventricular septum or left ventricular wall. Inflammation in the RV wall of ARVC/D patients can be detected non-invasively with the combined analysis of plasma levels of inflammatory cytokines and cardiac Ga-67 scintigraphy