The comparison of angiographic lesions and clinical outcomes in identical twins.

Both genetic and environmental factors are involved in the development of coronary artery disease (CAD). The degree of contribution of each individual risk factor on CAD is unknown. The extent to which the familial occurrence of coronary heart disease is due to genetic mechanisms can be assessed in twins. In our opinion, due to the chance of mortality risk in monozygotic twin being about 20 times higher than for a representative individual in the overall population, and 3.2- to six-fold higher than for the dizygotic twin of a patient with myocardial infarction, aggressive cardiac evaluation is essential for the asymptomatic twin especially if symptomatic pair's lesion is critical. This report describes similar coronary angiographic findings of identical twins with different coronary risk factors. They both underwent coronary bypass revascularization and had similar uneventful postoperative follow-up.