SPECT scan may predict. prognosis of hospitalized HF patients: Study

Cardiac sympathetic nerve dysfunction assessed by ¹²³I-MIBG imaging is associated with poor outcomes in chronic HF patients with reduced left ventricular ejection fraction (HFrEF). However, no information is available on the prognostic value of cardiac ¹²³I-MIBG SPECT imaging in patients with HFpEF.

A study was conducted by a group of researchers from Japan to elucidate the prognostic value of cardiac sympathetic nerve dysfunction as evaluated using iodine-123-labelled metaiodobenzylguanidine(¹²³I-MIBG) single-photon emission computed tomography (SPECT) imaging in patients with heart failure (HF) with preserved left ventricular ejection fraction (HFpEF).

The researchers studied 148 patients admitted for acute decompensated HF (ADHF) with nonischemic HFpEF and who underwent cardiac ¹²³I-MIBG imaging at discharge. The cardiac ¹²³I-MIBG heart-to-mediastinum ratio (H/M) was measured on the delayed planar image (late H/M). SPECT analysis of the delayed image was conducted, and the tracer uptake in all 17 regions on the polar map was scored on a 5-point scale by comparison with a sex-matched normal control database. The total defect score (TDS) was calculated by summing the score of each of the 17 segments. The primary endpoint was the association between TDS and cardiac events (the composite of emergent HF hospitalization and cardiac death).

The results of the study are as follows:

• During a mean follow-up period of 2.4 ± 1.6 years, 61 patients experienced cardiac events.
• TDS was significantly associated with cardiac events after multivariate Cox adjustment
• Patients with high TDS levels had a significantly greater risk of cardiac events than those with middle or low TDS levels.
• C-statistic of TDS was 0.730 which was significantly higher than that of late H/M.

Thus, the researchers concluded that Cardiac ¹²³I-MIBG SPECT imaging provided useful prognostic information in nonischemic ADHF patients with HFpEF.

Reference:

Prognostic Significance of Cardiac 123I-MIBG SPECT Imaging in Heart Failure Patients with Preserved Ejection Fraction by Masahiro Seo et al. published in the JACC: Cardiovascular Imaging.

https://doi.org/10.1016/j.jcmg.2021.08.003