Is TOMPOOL (gated blood-pool SPECT processing software) accurate to diagnose right and left ventricular dysfunction in a clinical setting?

Background: The assessment of right ventricular function is crucial for management of heart disease. TOMPOOL is a software that processes data acquired with Tomographic Equilibrium Radionuclide Ventriculography. In this report, TOMPOOL's diagnostic accuracy and inter-observer reproducibility were assessed in a cohort of patients with various etiologies of ventricular dysfunction.

Methods And Results: End-diastolic volume (EDV), ejection fraction (EF), and cardiac output (CO) were calculated for the right ventricle (RV) and the left ventricle (LV) using TOMPOOL in 99 consecutive patients. Thirty-five patients underwent cardiac magnetic resonance imaging (CMR) considered as the reference-standard to measure EDV and EF; the Spearman's rho correlation coefficients were r = 0.73/0.80 and 0.67/0.73 for right/left EF and EDV, respectively. Twenty-one patients had thermodilution measurements of right CO (reference-standard), the correlation was r = 0.57. The best cut-off points (sensitivity/specificity) in order to diagnose a ventricular dysfunction or enlargement were 46% for RVEF (67%/89%), 62% for LVEF (100%/90%), 94 mL for RVEDV (77%/73%), and 84 mL for LVEDV (100%/91%). The areas under the ROC curve were, respectively, 0.79, 0.91, 0.83, and 0.99. Inter-observer reproducibility was r = 0.81/0.94, 0.77/0.90, and 0.78/0.75 for Right/Left EF, EDV, and CO, respectively.

Conclusion: TOMPOOL is accurate: measurements of EDV, EF, and CO are reproducible and correlate with CMR and thermodilution. However, thresholds must be adjusted.