Incremental prognostic value of cardiac iodine-123 metaiodobenzylguanidine imaging over plasma volume status in patients admitted for acute decompensated heart failure

Abstract Background Plasma volume expansion plays an essential role in heart failure and plasma volume status (PVS) has been evaluated as a prognostic marker for heart failure. Cardiac iodine-123 metaiodobenzylguanidine (MIBG) imaging provides prognostic information in patients with heart failure. We sought to prospectively investigate the incremental prognostic value of cardiac MIBG imaging over PVS in patients admitted for acute decompensated heart failure (ADHF). Methods and results We studied 549 consecutive patients admitted for ADHF and discharged with survival in our prospective cohort study. Venous sampling and cardiac MIBG imaging were performed just before discharge. The PVS was calculated with the Hakim formula. In MIBG imaging, the cardiac MIBG heart-to-mediastinum ratio (late HMR) was measured on the delayed image. During a follow-up period of 4.9 ± 3.2 years, 384 patients reached the composite endpoints (all-cause death and unplanned hospitalization for worsening heart failure). At the multivariable Cox analysis, late HMR and PVS were significantly associated with composite endpoints after adjustment of major confounders. In both high and low PVS subgroups (≥3.36 and 3.36, respectively: determined by ROC analysis: AUC 0.70, p0.001), patients with low late HMR (1.66: median value) had a significantly greater risk of event than those with higher late HMR (high PVS group: 74% vs 63%, p=0.0034, adjusted HR 1.43 1.14–1.79; low PVS group: 47% vs 28%, p=0.0064, adjusted HR 1.92 1.25-2.99). Conclusion The combination of cardiac MIBG imaging and plasma volume status could be useful for stratifying patients at risk for all-cause death and unplanned heart failure hospitalization in patients admitted for acute decompensated heart failure.