TY - JOUR
T1 - Incidence of abnormal positron emission tomography in patients with unexplained cardiomyopathy and ventricular arrhythmias
T2 - The potential role of occult inflammation in arrhythmogenesis
AU - Tung, Roderick
AU - Bauer, Brenton
AU - Schelbert, Heinrich
AU - Lynch, Joseph P.
AU - Auerbach, Martin
AU - Gupta, Pawan
AU - Schiepers, Christiaan
AU - Chan, Samantha
AU - Ferris, Julie
AU - Barrio, Martin
AU - Ajijola, Olujimi
AU - Bradfield, Jason
AU - Shivkumar, Kalyanam
PY - 2015/12/1
Y1 - 2015/12/1
N2 - Background The incidence of myocardial inflammation in patients with unexplained cardiomyopathy referred for ventricular arrhythmias (VAs) is unknown. Objective The purpose of this study was to report fasting positron emission tomographic (PET) scan findings in consecutive patients referred with unexplained cardiomyopathy and VA. Methods Fluorine-18 fluoro-2-deoxyglucose (18-FDG) PET/computed tomographic (CT) scans with a >16-hour fasting protocol were prospectively ordered for patients referred for VA and unexplained cardiomyopathy (ejection fraction <55%). Patients with focal myocardial FDG uptake were labeled as arrhythmogenic inflammatory cardiomyopathy (AIC) and classified into 4 groups based on the presence of lymph node uptake (AIC+) and perfusion abnormalities (early vs late stage). Results Over a 3-year period, 103 PET scans were performed, with 49% (AIC+ 17, AIC 33) exhibiting focal FDG uptake. Mean patient age was 52 ± 12 years (ejection fraction 36% ± 16%). Patients with AIC were more likely to have a history of pacemaker (32% vs 6%, P =.002) compared to those with normal PET. When biopsy was performed, histologic diagnosis revealed nongranulomatous inflammation in 6 patients and sarcoidosis in 18 patients. Ninety percent of patients with AIC/AIC+ were prescribed immunosuppressive therapy, and 58% underwent ablation. Correlation between low voltage regions on electroanatomic mapping and FDG uptake was observed in 74%. Magnetic resonance imaging findings matched abnormal PET regions in only 40%. Conclusion Nearly 50% of patients referred with unexplained cardiomyopathy and VA demonstrate ongoing focal myocardial inflammation on FDG PET. These data suggest that a significant proportion of patients labeled "idiopathic" may have occult AIC, which may benefit from early detection and immunosuppressive medical therapy.
AB - Background The incidence of myocardial inflammation in patients with unexplained cardiomyopathy referred for ventricular arrhythmias (VAs) is unknown. Objective The purpose of this study was to report fasting positron emission tomographic (PET) scan findings in consecutive patients referred with unexplained cardiomyopathy and VA. Methods Fluorine-18 fluoro-2-deoxyglucose (18-FDG) PET/computed tomographic (CT) scans with a >16-hour fasting protocol were prospectively ordered for patients referred for VA and unexplained cardiomyopathy (ejection fraction <55%). Patients with focal myocardial FDG uptake were labeled as arrhythmogenic inflammatory cardiomyopathy (AIC) and classified into 4 groups based on the presence of lymph node uptake (AIC+) and perfusion abnormalities (early vs late stage). Results Over a 3-year period, 103 PET scans were performed, with 49% (AIC+ 17, AIC 33) exhibiting focal FDG uptake. Mean patient age was 52 ± 12 years (ejection fraction 36% ± 16%). Patients with AIC were more likely to have a history of pacemaker (32% vs 6%, P =.002) compared to those with normal PET. When biopsy was performed, histologic diagnosis revealed nongranulomatous inflammation in 6 patients and sarcoidosis in 18 patients. Ninety percent of patients with AIC/AIC+ were prescribed immunosuppressive therapy, and 58% underwent ablation. Correlation between low voltage regions on electroanatomic mapping and FDG uptake was observed in 74%. Magnetic resonance imaging findings matched abnormal PET regions in only 40%. Conclusion Nearly 50% of patients referred with unexplained cardiomyopathy and VA demonstrate ongoing focal myocardial inflammation on FDG PET. These data suggest that a significant proportion of patients labeled "idiopathic" may have occult AIC, which may benefit from early detection and immunosuppressive medical therapy.
KW - Cardiomyopathy
KW - Inflammation
KW - Positron emission tomography
KW - Ventricular arrhythmia
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U2 - 10.1016/j.hrthm.2015.08.014
DO - 10.1016/j.hrthm.2015.08.014
M3 - Article
C2 - 26272522
AN - SCOPUS:84960098564
VL - 12
SP - 2488
EP - 2498
JO - Heart Rhythm
JF - Heart Rhythm
SN - 1547-5271
IS - 12
ER -