Inclusion Criteria:

Coronary Artery Disease: Previous MI (> 2 days prior to informed consent), or stable or previous unstable angina (> 30 days prior to informed consent) with documented multivessel coronary artery disease or a positive stress test, or multivessel PTCA (> 30 days prior to informed consent), or previous multivessel CABG without angina (if surgery performed > 4 years prior to informed consent) or with recurrent angina after surgery.

Other High Risk:

1. Peripheral Arterial Disease: Previous limb bypass surgery or angioplasty or amputation, intermittent claudication on history with ankle/arm BP ratio < 0.8 on at least one side, or significant stenosis by angiography or non-invasive testing
2. Previous stroke
3. TIA > 7 days and < 1 year prior to informed consent
4. Diabetes Mellitus (types I or II): with evidence of end-organ damage (retinopathy, LVH, micro or macro albuminuria), or any evidence of previous cardiac or vascular disease. No definite and specific indication or contraindication for any of the study treatments.

Written informed consent.

Exclusion Criteria:

A. Medication use:

1. Inability to discontinue ACE-inhibitors or AIIA.
2. Patients with known hypersensitivity or intolerance to AIIAs or ACE-inhibitors. NOTE: Patients with known intolerance to ACE-I can be enrolled in the TRANSCEND study.

B. Cardiovascular disease:

1. Symptomatic congestive heart failure.
2. Hemodynamically significant primary valvular or outflow tract obstruction (e.g. aortic or mitral valve stenosis, asymmetric septal hypertrophy, malfunctioning prosthetic valve).
3. Constrictive pericarditis.
4. Complex congenital heart disease.
5. Syncopal episodes of unknown etiology < 3 months before informed consent.
6. Planned cardiac surgery or angioplasty within three months.
7. Uncontrolled hypertension on treatment (i.e. BP > 160/100).
8. Heart transplant recipient.
9. Strokes due to subarachnoid hemorrhage

C. Other conditions:

1. Significant renal disease defined as:

   1. Renal artery stenosis;
   2. Creatinine clearance < 0.6 ml/min or serum creatinine > 265 umol/L (> 3.0 mg/dL);
   3. Hyperkalemia: potassium > 5.5 mmol/L.
   4. Proteinuria* (for TRANSCEND only).
2. Hepatic dysfunction as defined by the following laboratory parameters: SGPT (ALT) or SGOT (AST) > than 4 times upper limit of normal or additional criteria for hepatic impairment the upper limit of normal range, total Bilirubin > 20 umol/L, biliary obstructive disorders.
3. Uncorrected volume depletion or sodium depletion.
4. Primary aldosteronism.
5. Hereditary fructose intolerance.
6. Any other major non-cardiac illness expected to reduce life expectancy or interfere with study participation.
7. Patient is simultaneously taking another experimental drug.
8. Patient with significant disability that precludes regular attendance at clinic for follow-up.
9. Patient has sufficient disability or other incapacity that precludes regular attendance at clinic for follow-up.
10. Unable or unwilling to provide written informed consent.