Incremental prognostic value of cardiac metaiodobenzylguanidine imaging over the co‐morbid burden in acute decompensated heart failure

AIMS: Co‐morbidities are associated with poor clinical outcomes in patients with chronic heart failure, while cardiac iodine‐123 (I‐123) metaiodobenzylguanidine (MIBG) imaging provides prognostic information in such patients. We sought to prospectively investigate the incremental prognostic value of cardiac MIBG imaging over the co‐morbid burden, in patients admitted for acute decompensated heart failure (ADHF). METHODS AND RESULTS: In 433 consecutive ADHF patients with survival to discharge, we measured the co‐morbidity using age‐adjusted Charlson co‐morbidity index (ACCI), commonly employed to evaluate a weighted and scored co‐morbid condition, adding additional points for age. In cardiac MIBG imaging, the cardiac MIBG heart‐to‐mediastinum ratio (late HMR) was measured on the delayed image. Over a follow‐up period of 2.9 ± 1.5 years, 160 patients had a cardiac event (a composite of cardiac death and unplanned hospitalization for worsening heart failure). Patients with high ACCI (≥6: median value) had a significantly greater risk of a cardiac event. In multivariate Cox analysis, the ACCI and late HMR were significantly and independently associated with a cardiac event. In both high and low ACCI subgroups (ACCI ≥ 6 and <6, respectively), patients with low late HMR had a significantly greater risk of a cardiac event (high ACCI: 51% vs. 34% P = 0.0026, adjusted HR 1.74 [1.21–2.51]; low ACCI: 34% vs. 17%, P = 0.0228, adjusted HR 2.19 [1.10–4.37]). CONCLUSIONS: Cardiac MIBG imaging could provide additional prognostic information over ACCI, which was also promoted to be a useful risk model, in patients admitted for ADHF.