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

Purpose: 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).

Methods: 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.

Results: 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).

Conclusions: 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.