Blood Oxygen Level Dependent (BOLD) Cardiovascular Magnetic Resonance (CMR) as Predictor of Cardiac Prognosis in Asymptomatic Chronic Kidney Disease (CKD) Patients

Background: Current invasive and non-invasive diagnostic approaches are poorly predictive of future cardiovascular events, and in particular the risk of sudden cardiac death (SCD). We hypothesised that blunted myocardial oxygenation response to stress (defined by negative BOLD Signal Intensity (SI) Change value) could be an independent predictor for cardiovascular events in asymptomatic CKD patients. Methods: Participants with pre-existing CKD (CKD+) with no established coronary artery disease underwent BOLD CMR scanning at 3 Tesla. BOLD images were acquired at rest and with adenosine stress. BOLD Signal Intensity Change was assessed semi-quantitatively. Patients were prospectively followed for major adverse cardiac events (MACE), defined as cardiovascular death, myocardial infarction, ventricular arrhythmia and pulmonary oedema. Results: The mean follow-up was 20± 12 months. Ten patients (26%) had MACE (p= 0.01): four (10%) deaths, four (10%) non-fatal myocardial infarctions, two (5%) heart failure. [8 out of 20 (44%) in CKD patients with negative BOLD SI Change had MACE versus 1 out of 16 (6%) in CKD patients without negative BOLD SI Change had MACE, p= 0.026)]. On multivariate analysis, the negative BOLD SI Change value was independently associated with MACE (Hazard Ratio 19.48, 95% CI 1.28 - 295.44, p= 0.03). CKD patients with negative BOLD SI Change value had reduced MACE-free survival compared to CKD patients with positive BOLD SI Change value (p =0.03). Conclusion: Blunted myocardial oxygenation response to stress could be a predictor of major adverse cardiovascular events in patients with CKD. Non-contrast BOLD CMR is a promising prognostic tool to assess silent myocardial ischaemia in CKD patients. Further studies in larger patient populations are warranted.