Prognostic significance of cardiac I-123-metaiodobenzylguanidine imaging in patients with reduced, mid-range, and preserved left ventricular ejection fraction admitted for acute decompensated heart failure: a prospective study in Osaka Prefectural Acute Heart Failure Registry (OPAR)

Aims Cardiac I-123-metaiodobenzylguanidine (I-123-MIBG) imaging provides prognostic information in patients with chronic heart failure (HF). However, there is little information available on the prognostic role of cardiac I-123-MIBG imaging in patients admitted for acute decompensated heart failure (ADHF), especially relating to reduced ejection fraction [HFrEF; left ventricular ejection fraction (LVEF) < 40%], mid-range ejection fraction (HFmrEF; 40% <= LVEF < 50%) and preserved ejection fraction (HFpEF; LVEF >= 50%). Methods and results We studied 349 patients admitted for ADHF and discharged with survival. Cardiac I-123-MIBG imaging, echocardiography, and venous blood sampling were performed just before discharge. The cardiac I-123-MIBG heart-to-mediastinum ratio (late H/M) was measured on the chest anterior view images obtained at 200 min after the isotope injection. The endpoint was cardiac events defined as unplanned HF hospitalization and cardiac death. During a follow-up period of 2.1 +/- 1.4 years, 128 patients had cardiac events (45/127 in HFrEF, 28/78 in HFmrEF, and 55/144 in HFpEF). On multivariable Cox analysis, late H/M was significantly associated with cardiac events in overall cohort (P = 0.0038), and in subgroup analysis of each LVEF subgroup (P = 0.0235 in HFrEF, P = 0.0119 in HFmEF and P = 0.0311 in HFpEF). Kaplan-Meier analysis showed that patients with low late H/M (defined by median) had significantly greater risk of cardiac events in overall cohort (49% vs. 25% P < 0.0001) and in each LVEF subgroup (HFrEF: 48% vs. 23% P = 0.0061, HFmrEF: 51% vs. 21% P = 0.0068 and HFpEF: 50% vs. 26% P = 0.0026). Conclusion Cardiac sympathetic nerve dysfunction was associated with poor outcome in ADHF patients irrespective of HFrEF, HFmrEF, or HFpEF.

Automated summary

This study found that cardiac sympathetic nerve dysfunction was associated with poor outcomes in patients admitted for acute decompensated heart failure, regardless of reduced ejection fraction (HFrEF), mid-range ejection fraction (HFmrEF), or preserved ejection fraction (HFpEF) status.