Table 1.

Enrollment Criteria

Inclusion criteria

1. MZ twins and same‐sex DZ twins

2. Females age 40 to 75 years, males age 35 to 75 years

3. A signed IRB/ethics committee–approved informed consent form

Exclusion criteria

1. Subjects for whom coronary CTA is contraindicated per institutional standard of carea

2. Subjects with previous coronary arterial revascularization (PCI or CABG)

3. Subjects with AF/flutter or frequent irregular or rapid heart rhythms occurring within the past 3 months

4. Subjects with a pacemaker or ICD implant

5. Active CHF or the presence of known nonischemic cardiomyopathy

6. Known genetic disorders of atherosclerosis, lipid, or lipoprotein metabolism

Abbreviations: AF, atrial fibrillation; CABG, coronary artery bypass grafting; CHF, congestive heart failure; CTA, computed tomography angiography; DZ, dizygotic; ICD, implantable cardioverter‐defibrillator; IRB, institutional review board; MZ, monozygotic; PCI, percutaneous coronary intervention.

^aHistory of severe and/or anaphylactic contrast reaction, inability to cooperate with scan acquisition and/or breathhold instructions, pregnancy, clinical instability, and renal insufficiency.