Diabetics With Acute Chest Pain Have Similar Length of ED Stay From Early CCTA Compared to Standard Evaluation but More Downstream Testing and Radiation Exposure: The ROMICAT II Trial

Objective: In the evaluation of acute chest pain (ACP), early cardiac computed tomographic angiography reduces emergency department (ED) length of stay (LOS) compared with standard evaluation. It is unknown whether patients with diabetes mellitus (DM) have similar benefits. Methods: In the ROMICAT II multicenter trial, we randomized 1000 patients (17.3% DM) 40-74 years old with symptoms suggestive of acute coronary syndrome (ACS) but without ischemic ECG changes or initial positive troponin to early CCTA or standard ED evaluation. In this pre-specified analysis, we compared differences between the two strategies for the primary endpoint of LOS in DM and non-DM patients. Secondary endpoints were examined in Table 1. Results: ACS rate was similar between DM and non-DM (both 7.5%, p=1.0). DM (70% on oral hypoglycemics, 25% insulin) were older (57 vs 54 years) with more cardiac risk factors, though more frequently female (56%) and on cardiac medications than non-DM (all p<0.001). Table 1 shows the effects of early CCTA versus standard evaluation in DM and non-DM groups. LOS was unaffected by CCTA strategy in DM, whereas LOS was significantly reduced in non-DM. Early CCTA was associated with higher rates of direct ED discharge in both groups, but hospital admissions were significantly reduced with CCTA only in non-DM. Although both groups had more downstream testing and higher radiation dose with CCTA, these differences were accentuated in DM (all p-interaction≤0.04). There was no missed ACS. More DM had abnormal CCTA than non-DM (68% vs 50%, p=0.003), but among DM with no CAD or non-obstructive CAD (69%) by CCTA, LOS was similar compared to non-DM patients (p=NS). Conclusions: An early CCTA strategy in the ED was associated with shorter LOS in non-DM but not in the DM group. The higher prevalence of CAD in DM and direct visualization of atherosclerosis by CCTA may explain the increased testing and radiation exposure with CCTA that were accentuated in DM.