Influence of Pulse Electromagnetic Field Therapy on Myocardial Ischemia

Inclusion Criteria:

* Age ≥ 18 years old.
* Known cardiac ischemia, who are non revascularizable, or have not and will not be undergo coronary intervention for the duration of their participation in the study.
* Evidence of ischemia from previous clinical tests (echo, nuclear, standard ECG from past 6 months).
* Left Ventricular Ejection fraction \> 40% by echo (evaluated last 3 months).
* Able to complete a cardiopulmonary exercise test without significant non cardiac limitations, primarily orthopedic.
* On guideline directed optimal therapy for stable ischemia.

Exclusion Criteria:

* Anemia (\< 7 mg/dl).
* Low potassium (\< 3 mmol/L).
* Creatinine (\> 5.0 mg/dl or \< 0.6 mg/dl).
* Unable to exercise due primarily to orthopedic limitation.
* Severe lung disease.
* Morbid obesity (BMI \> 42).
* Pregnant.
* Breast feeding.
* Significant arrhythmia (ventricular tachycardia, ventricular fibrillation, frequent premature ventricular contractions (PVCs), persistent atrial fibrillation, or 2nd or 3rd degree atrioventricular (AV) block).
* Seizures.
* Unstable angina.
* Coronary spasm.
* Recent myocardial infarction (\< 90 days).
* Recent percutaneous coronary intervention (\<90 days).