Using Magnetic Resonance Imaging to Evaluate Heart Vessel Function After Angioplasty or Stent Placement Procedures

Microvascular Obstruction by Contrast-enhanced MRI Following Percutaneous Coronary Interventions

Coronary artery disease (CAD) is caused by a narrowing of the blood vessels that supply blood and oxygen to the heart. Balloon angioplasty and stent placement are two treatment options for people with reduced heart function caused by CAD. This study will use magnetic resonance imaging (MRI) procedures to evaluate heart function over time in people with CAD who have undergone a balloon angioplasty or stent placement procedure.

CAD is the most common type of heart disease in the United States. It occurs when the arteries that supply blood to the heart become hardened and narrowed because of a build-up of cholesterol and plaque on the inner walls of the arteries. Over time, less blood is able to flow through the arteries, depriving the heart of the blood and oxygen it needs. If left untreated, CAD can lead to heart failure, heart attack, and arrhythmias. Someone with plaque build-up may undergo a percutaneous coronary intervention (PCI) to unblock the narrowed arteries and increase blood flow. PCI encompasses a variety of procedures, including balloon angioplasty and stent placement. In balloon angioplasty, a small balloon is inserted into the heart artery and then inflated. This pushes the plaque against the artery walls and widens the artery. Stents are wire mesh tubes that are permanently implanted in the artery to keep it propped open. Although balloon angioplasty and stent placement procedures open up blockages in the large vessels of the heart, the tiny vessels of the heart may become blocked after these procedures, which may affect how the heart heals. This study will use MRI to examine heart function in people who have undergone PCI procedures. Study researchers will attempt to define how often blockages of the tiny vessels occur after PCI procedures, the factors that lead to the blockages, and how often blockages affect healing of the heart.

This study will enroll people who are undergoing a PCI procedure. Participants will undergo an MRI scan of the heart before and after the PCI procedure. During the 72 hours after the procedure, electrocardiogram (EKG) will be used to monitor heart electrical activity. At a study visit 10 days after the PCI procedure and at a follow-up visit 6 to 12 months later, participants will undergo an MRI, EKG, and blood collection. Study staff will call participants every 6 months for 5 years to collect medical information.

Inclusion Criteria:

• Undergoing diagnostic coronary angiography
• Undergoing percutaneous coronary intervention

Exclusion Criteria:

• Clinically unstable (i.e., demonstrates unstable cardiac rhythm or hemodynamics, supported on vasopressors or an intra-aortic balloon pump, and/or is actively ischemic) at the time of the MRI procedure
• Unable to undergo MRI procedure (e.g., has non-MRI compatible implanted metallic objects, including cardiac pacemakers or cerebral aneurysm clips that are not MRI compatible)
• Current glomerular filtration rate of less than 60mL/min/1.73m2
• Pregnant