Combined delivery approach of bone marrow mononuclear stem cells early and late after myocardial infarction: the MYSTAR prospective, randomized study.

Background: Combined intracoronary and intramyocardial administration might improve outcomes for bone-marrow-derived stem cell therapy for acute myocardial infarction (AMI). We compared the safety and feasibility of early and late delivery of stem cells with combined therapy approaches.

Methods: Patients with left ventricular ejection fraction less than 45% after AMI were randomly assigned stem cell delivery via intramyocardial injection and intracoronary infusion 3-6 weeks or 3-4 months after AMI.