Hyperbaric Oxygen Therapy in Patients With Chronic Stable Ischemic Heart Disease: An Option for Therapeutic Angiogenesis?

Inclusion Criteria: * Age 21 years or older. * Symptomatic or asymptomatic chronic ischemic heart disease patients, with no more than moderate systolic dysfunction (EF\>30%) on optimal medical treatment who have been evaluated for myocardial ischemia using myocardial perfusion study and coronary angiography. * Patients who demonstrate significant myocardial perfusion defect, defined as ≥5% global perfusion defect and/or ≥3 segments with perfusion defect out of 17 myocardial segments, and were found to have coronary artery disease not amenable for PCI or CABG (or re-CABG) due to anatomical or medical considerations. * Clinical stable patients in the 3 months before randomization. Good functional class as determinate by the New York Heart association functional status I-III and Canadian Cardiovascular Society Angina class I-III. Optimal medical therapy defined by chronic regular use of a combination of more than 3 antianginal medications (beta blockers, calcium channel blockers, nitrates, unless contraindicated for any reason) and/or secondary prevention drugs (aspirin, aldosterone antagonists, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, statins, unless contraindicated for any reason). Exclusion Criteria: * Current smokers or smoking patients who could not comply with the demand to cease smoking prior to inclusion. * Had been treated with HBOT for any other reasons prior to their inclusion * Have any other indication for HBOT; * Chest pathology incompatible with pressure changes; * Inner ear disease; * Patients suffering from claustrophobia; * Inability to sign written informed consent. * Patients unable to perform exercise tolerance test for any reason * Hospital admission due to acute coronary syndrome or congestive heart failure exacerbation in the past 3 month before randomization * r CCS class IV angina * Patients currently in NYHA functional class IV * Severe or uncontrolled other medical illness as advanced liver, kidney or oncologic diseases