Long-term prognostic value of vasodilator stress perfusion cardiovascular magnetic resonance in diabetic patients

Abstract Background The benefit of screening for coronary artery disease (CAD) in diabetic patients and the adequate stress-test to use are not well established. Although stress cardiovascular magnetic resonance (CMR) has a good prognostic value in large cohorts of patients, its prognostic value in a dedicated cohort of diabetic patients has not been evaluated. Purpose The aim of this study was to assess the long-term prognostic value of vasodilator stress perfusion CMR in diabetic patients. Methods Between December 2008 and January 2022, we conducted a multicentre longitudinal study with consecutive diabetic patients, referred for vasodilator stress perfusion CMR to 3 hospitals. The primary outcome was all-cause death defined by the National Death Registry. Univariable and multivariable Cox regressions for all-cause death were performed to determine the prognostic value of inducible ischaemia and unrecognised myocardial infarction (MI) by CMR. Results Among 13,911 patients (mean age 64.3± 12 years; 69.5% males) with a median follow up of 7.3 years, 1,429 (10.3%) died. Patients without inducible ischaemia experienced a lower rate of all-cause death than those with an inducible ischaemia (9.4 versus 15.0%, respectively, p0.001). In univariate analysis, the extent of inducible ischaemia and unrecognised MI were significantly associated with the occurrence of all-cause death (hazard ratio HR per segment: 1.17; 99.5% confidence interval CI: 1.13-1.21 and HR: 1.25, 99.5%CI: 1.20-1.29, respectively; both p0.001). In multivariable analysis, the extent of inducible ischaemia and unrecognised MI were independent predictors of a higher incidence of all-cause death (HR per segment: 1.13, 99.5% CI: 1.09-1.18, and HR: 1.14, 99.5%CI: 1.09-1.19 respectively, both p0.001). These findings were consistent in all subgroups, including in patients with or without a known CAD; and in both symptomatic and asymptomatic patients. In patients with ischaemia, CMR-guided coronary revascularisation was associated with a lower rate of all-cause death (HR: 0.28, 99.5%CI: 0.20-0.39, p0.001). After adjustment, stress CMR showed the best improvement in model discrimination and reclassification above traditional prognostic factors (C-statistic improvement:0.01; net reclassification improvement: 0.185; integrative discrimination index: 0.046; both p0.001). Conclusions In patients with diabetes mellitus, vasodilator stress CMR has independent and incremental prognostic value to predict all-cause death over traditional prognostic factors.