Cardiovascular disease which includes coronary artery disease and peripheral artery disease remains the leading cause of death among women in the United States. The impact of cardiovascular in women was not recognized by clinicians for a long time. It is now evident that, women suffer the consequences of cardiovascular at rates at least as high as those observed in men but there are still major gaps in our understanding this disease in women. Hydrogen sulfide (H2S), a gaseous mediator plays an important role in the cardiovascular system. Research has demonstrated it's critical role in animal ischemia reperfusion models. Hydrogen sulfide exists in distinct biological pools in blood. Recently, the Kevil lab has pioneered the development of new analytical techniques for accurate measurement of all biological pools of H2S. By measuring these distinct pools of H2S in women with and without cardiovascular disease the investigators hope to further understanding of role of H2S in pathophysiology of cardiovascular disease. This research will help to assess the ability of H2S and its distinct biological pools to potentially be a diagnostic marker or a therapeutic target for cardiovascular disease.

Inclusion Criteria:

1. Patients presenting to the cardiac catheterization laboratory for coronary or peripheral angiography.
2. Females,Age>40years

Exclusion Criteria:

1. Inability to provide informed consent.
2. STelevationmyocardialinfarction.
3. Cardiogenicshock.

3. ABI >1.4 (indicative of non-compressible vessel needing further evaluation to diagnose PAD), unless documented known PAD. 4. Non-atheroscleroticPAD(e.g.Buerger'sdisease). 5. Enrolment in another clinical trial with use of experimental therapeutic agents.

Female subjects scheduled to undergo left heart catheterization or peripheral angiography at LSUHSC Shreveport cardiac catheterization laboratory will be given the opportunity to participate. Controls will be recruited via flyers posted in various parts of LSUHSC Shreveport.