Impact of Ranolazine on Coronary Microcirculatory Resistance

Inclusion Criteria:

- - Patients with subjective symptoms of ischemia without flow limiting angiographic
CAD (<50% epicardial coronary stenosis) and abnormal IMR (>20 U).

- Definition of ischemia (any one):

- chest pain with dynamic ischemic ECG changes (t wave inversions or > 1 mm ST
depressions

- Exercise treadmill testing induced chest pain with ≥1 mm of downsloping or flat
ST segment depression during exercise or recovery; ≥2 mm of ischemic ST
depression at a low workload (stage 2 or less or ≤130 beats/min); early onset
(stage 1) or prolonged duration (>5 min) of ST depression; multiple leads (>5)
with ST depression

- Nuclear stress perfusion defect > 10%

- Stress echocardiogram with stress induced wall motion abnormality

Exclusion Criteria:

- - Age < 18 yrs

- Flow Limiting epicardial CAD >50%

- Life expectancy < 6 months

- Recent (<1 week) myocardial infarction or positive biomarkers

- Severe aortic stenosis

- Contraindications to IMR testing including inability to utilize antithrombotic
therapy and/or intravenous adenosine

- Contraindications to Ranolazine therapy:

- Patients with known hepatic insufficiency, prolonged QT or renal failure (GFR < 60)

- use of drugs that inhibit CYP3A such as diltiazem, verapamil, ketoconazole,
macrolides and HIV protease inhibitors

- Pregnancy, breastfeeding

- Patients taking drugs which prolong QT interval