Establishment of a ¹²³I-meta-iodobenzylguanidine normal database for D-SPECT using Japanese and Italian data

We aimed to develop ¹²³I-meta-iodobenzylguanidine (MIBG) normal databases (NDBs) for D-SPECT that included Japanese and European populations and to validate the ability of combined NDBs to diagnose heart failure (HF).

This study included 55 Japanese and 33 Italian patients without cardiac or neurological diseases associated with Lewy bodies. Single-photon emission computed tomography (SPECT) images were acquired 20 min and 3-4 h after ¹²³I-MIBG injection. We established NDBs for Japanese (Jp-NDB) and Italian (It-NDB) patients, and combined them (JpIt-NDB) using 17-segment polar maps. We also compared the Jp- with the Anger camera NDB established by the Japanese Society of Nuclear Medicine and clinically validated our findings in a cohort of 31 patients with HF.

The average uptake in the anterior segments was lower in the It-NDB and differences were more pronounced in males. The JpIt-NDB closely aligned with both the Jp-NDB and It-NDB. Clinical validation indicated that HF was identified more accurately by automated defect scores derived from the JpIt-NDB than visual scores (area under the receiver operating characteristic (ROC) curve (AUC): 0.827 vs. 0.683; P = 0.032). Combining JpIt-NDB-derived scores based on the heart-to-mediastinum ratio (HMR) significantly enhanced diagnostic accuracy (early and late AUCs: 0.960 and 0.952, respectively).

The combined JpIt-NDB accurately diagnosed HF in Japanese and European patients, while the defect scores correlated closely to Jp- and It-NDBs. Integrated HMR and NDB defect scores significantly enhanced cardiac assessment precision, which offers promise for future investigations into cardiac innervation imaging.