Detection of Diffuse Scar in Patients With Diabetes

For PHASE I (Prospective Cohort Study to determine prognostic value of fibrotic index) Inclusion Criteria: * Diabetes mellitus, type II * Age \>= 40 years * UKPDS 10 year Risk Score \> 15% * Low risk stress test (defined explicitily in our protocol) Exclusion Criteria: * suspected or confirmed myocarditis or infiltrative disease (including hemochromatosis, sarcoid, or amyloid) * history of prior MI or coronary revascularization (by Q waves on electrocardiogram in 2 contiguous leads or by clinical history) * clinical HF (with prior hospital admission for HF or documentation of reduced LV ejection fraction after index CMR) * metallic hazards * hematocrit \< 30% (within 1 year of nuclear stress test) or history of active bleeding (within 3 months of stress test) * estimated GFR (by Modified Diet in Renal Disease) \< 45 ml/min/1.73m2 (within 2 weeks of planned CMR) * pregnancy * severe non-cardiac illness that or prognosis (e.g., end stage liver disease, malignancy, advanced HIV/AIDS) For PHASE 2: Inclusion Criteria: * Included in Phase I * Systolic blood pressure \> 140 mmHg on two occasions (at the initial nuclear stress test and at the index cardiac MRI) Exclusion criteria: 1. Concomitant cytochrome P450 (CYP3A4) inhibitors or inducers; 2. Concomitant potassium supplementation or potassium sparing diuretics; 3. Concomitant use of both ACE inhibitor and ARB therapy (at any dose); 4. Renal dysfunction (GFR \< 50 ml/min or serum creatinine \> 1.5 mg/dL (as assessed at time of index CMR); 5. Any urine microalbuminuria (as assessed at time of index CMR); 6. Baseline (pre-therapy) serum potassium \> 5.0 mEq/L; 7. Lack of reliable telephone contact number for relaying results or the need to discontinue drug therapy; 8. Age \> 75 years (given the tendency toward renal insufficiency not captured by GFR, dehydration and/or concomitant illness) 9. Women able to become pregnant (given the undefined risk of eplerenone therapy in pregnant women and newborns).