PGE1 Improves Coronary Microcirculation Dysfunction in Patients With CAD and Diabetes

Inclusion Criteria: 1. Patients giving written consent after being provided with sufficient explanation about participation in this clinical trial 2. Patients aged between 35-70, no limitation on gender 3. Patients with significant CAD and no need to PCI: 50%-70% luminal stenosis as determined by diagnostic coronary angiography, and left main coronary artery stenosis less than 50%; no history of revascularization procedures before 4. MPRI\<2.0 5. Type 2 DM patients with glycosylated hemoglobin levels\>7% 6. All patients were PGE1-naive, defined as receiving no PGE1 therapy for more than 7 days during the previous 12 months 7. Hypertension remained stable for last 3 months, patients with controlled BP level: SBP\<160mmHg and DBP\<95mmHg Exclusion Criteria: 1. Patients with a history of allergic to PGE1 or a history of prior PGE1 treatment. 2. History of revascularization procedures before: PCI or CABG 3. Patients with implanted pacemaker or ICD, ventricular assist device and intra-aortic balloon counter pulsation pump 4. Patients who have experienced myocardial infarction 5. Patients with serious systolic left ventricular function failure: echocardiography EF\<25% 6. Claustrophobia 7. Patients who used Insulin pumps 8. SBP\<90mmHg 9. Chronic renal function failure: creatinine level \>2.5mg/dl or 221umol/l 10. Patients with serious or frequent arrhythmia ,atrial fibrillation、frequent ventricular premature contraction、sick sinus syndrome, second- or third degree atrioventricular block 11. Prior non-cardiac illness with estimated life expectancy \<2-yrs 12. Women who are pregnant, lactation,or maybe pregnant in the study period 13. Unable to give informed consent