 Participation in this study will last 18 months. Potential participants will undergo initial screening 5 to 7 weeks prior to CABG surgery. Screening will include a physical exam, blood draw, pregnancy test, questions about medical history, current medications, and alcohol or drug use, an electrocardiogram ECG, magnetic resonance imaging MRI of the heart, questionnaires, an echocardiogram and a computed tomography CT scan. Eligible participants will then undergo two baseline visits within 6 weeks of their scheduled surgery. Baseline Visit 1 will consist of vital sign measurements, a bone marrow aspiration to obtain MSCs and a blood draw for a biomarker test. Baseline Visit 2 will include treadmill test, 6-minute walk test, pulmonary function FEV1 study and a 48 Hour Ambulatory ECG. After the second baseline visit, participants will be assigned randomly to receive either MSCs or placebo after surgery. 