Assessment of Left Internal Mammary Artery Graft Patency by Transthoracic Doppler Echocardiography

64 patients total: 22 patients (aged 62 +/- 8 years) with LIMA graft to the left anterior descending (LAD) coronary artery undergoing coronary angiography, 25 patients with angina (aged 59 +/- 12 years) with an ungrafted LIMA (control group A), and 17 patients (aged 59 +/- 9 years) with angiographically normal coronary arteries (control group B).

High-frequency (5 MHz) transthoracic Doppler echocardiography (TTE)

Coronary angiography (reference standard)

Detection of severe LIMA graft stenosis (>70%) using Doppler velocity patterns (diastolic velocity time integral fraction and systolic/diastolic peak velocity ratio)surrogate