This is a study of the perfusion of the myocardium in adults with specific forms of repaired congenital heart disease using established cardiac MRI techniques and correlating perfusion with clinical outcomes.

This is a study of the perfusion of the myocardium in adults with specific forms of repaired congenital heart disease using established cardiac MRI techniques and correlating perfusion with clinical outcomes. The investigators objectives are to examine myocardial perfusion both during stress and at rest in adults with repaired or palliated congenital heart disease as well as quantify ventricular function, regional myocardial strain and evidence of myocardial fibrosis with quantitative measures of myocardial perfusion. The specific aim of this study is to understand whether clinical subendocardial perfusion defects contribute to the late decompensation of adult subjects that have single ventricle physiology and adult subjects that have a systemic right ventricle.

Inclusion Criteria:

• Subjects 18 years of age or older
• All defects that have a right ventricle that supports the systemic circulation
• All defects with a functional single ventricle
• Written informed consent

Exclusion Criteria:

• Subjects with a contraindication to magnetic resonance imaging (MRI) scanning will be excluded. These contraindications include subjects with the following devices:

  • Central nervous system aneurysm clips
  • Implanted neural stimulator
  • Implanted cardiac pacemaker or defibrillator
  • Cochlear implant
  • Ocular foreign body (e.g. metal shavings)
  • Implanted Insulin pump
  • Metal shrapnel or bullet

• Severe heart damage that makes it difficult to breathe while lying flat

• Pregnant women (Women of childbearing potential who are uncertain as to whether they are pregnant will be required to have a screening urine or blood pregnancy test)

• Subjects with active symptoms of myocardial ischemia occurring despite maximally tolerated doses of oral antianginal therapy and intravenous nitroglycerin

• Furthermore, the following subject groups will be excluded from studies involving the administration of MRI contrast agents:

  • lactating women unless they are willing to discard breast milk for 24 hours after receiving gadolinium
  • renal disease (estimated glomerular filtration rate [eGFR] < 30 ml/min/1.73 m2 body surface area)

The eGFR will be used to estimate renal function if reported by the laboratory. Otherwise, estimated glomerular filtration rate (eGFR) can be based on the Modification of Diet in Renal Disease (MDRD) study equation (see below) in subjects with stable renal function. This formula is not applicable to subjects with acute renal insufficiency:

eGFR (ml/min/1.73 m2) = 175 x (serum creatinine)-1.154 x (age)-0.203 x 0.742 (if the subject is female) x 1.212 (if the subject is black)

Additional Exclusion Criteria for Vasodilator Stress MRI:

• Myocardial infarction within 24 hours
• Uncontrolled heart failure
• Uncontrolled asthma or emphysema
• Ventricular arrhythmia (sustained ventricular arrhythmia at the time of MR scan)
• Second degree heart block or higher

Primary care clinic

Results of MRI scans will be shared with the primary cardiologist.

MRI report becomes available once the scan has been assessed, usually within 24 hours. It will be available indefinitely.

Primary care takers will have access to this report.