Impact of Ranolazine on Myocardial Ischemia Detected by High-Field 3T Cardiovascular Magnetic Resonance (CMR) Imaging and P-31 Spectroscopy

Inclusion Criteria: 1. Age \>18 years of age with stable angina pectoris or an anginal equivalent symptom (e.g. atypical chest discomfort, dyspnea, easy fatigue) AND 2. Mild, moderate or severe myocardial ischemia detected on nuclear perfusion imaging (exercise or pharmacologic SPECT or Rubidium PET), exercise stress echocardiography or stress cardiac MRI OR Documentation of obstructive coronary artery with at least one major coronary artery (left anterior descending, circumflex or right coronary artery) of at least 70% by either conventional or CT coronary angiography. Exclusion Criteria: 1. Acute coronary syndrome including unstable angina or non ST elevation myocardial infarction within the last 60 days 2. ST-elevation myocardial infarction within 60 days 3. Equivocal myocardial ischemia on non-invasive testing or studies demonstrating reversible perfusion defects complicated by significant attenuation artifacts. 4. Recent PCI within the last 60 days 5. Recent CABG within the last 60 days 6. Inability to sign informed consent 7. Patients who have taken ranolazine within 30 days of screening 8. Patients taking strong CYP3A inhibitors e.g. ketoconazole, itraconazole, clarithromycin, nefazodone, nelfinavir, ritonavir, indinavir, and saquinavir 9. Patients taking inducers of CYP3A e.g. rifampin, rifabutin, rifapentine, phenobarbital, phenytoin, carbamazepine, and St. John's wort 10. Patients with liver cirrhosis or liver disease that is Grade B or C by the Child-Pugh Classification 11. Prior allergic reaction or intolerance to ranolazine 12. Patients with a history of inherited or acquired prolonged QT interval 13. Moderate to severe claustrophobia or previous inability to undergo an MRI exam 14. Patients with implanted pacemaker or internal cardiac defibrillator 15. Patients who have a metallic foreign body implants (metal silver in their eye, cochlear implants) or have an aneurysm clip in their brain 16. GFR \< 30 ml/m2 17. Type 2 second degree heart block (Mobitz II) in the absence of functioning permanent pacemaker. 18. Sinus node dysfunction in the absence of functioning permanent pacemaker. 19. Patients taking dipyridamole therapy. 20. Active bronchospasm (active asthma or COPD with active wheezing. \-