Discrepancy between angiography and intravascular ultrasound when analysing small coronary arteries

Aims: A small reference diameter may be the consequence of high plaque burden and diffuse disease. The reference vessel diameter in small coronary arteries may vary according to the method of measurement used. We endeavoured to confirm the difference between data from examinations conducted using angiography with that revealed by intravascular ultrasound. Methods and Results: Between March 1993 and October 1999, 344 consecutive patients with 419 lesions in small vessels (IVUS-Angio) was 1.3 ± 0.5 mm in the Small group and 1.04 ± 0.6 mm in the Large group (PIVUS-Angio in the Small group (r=0.80, PIVUS-Angio ≥ 0.30 mm occurred in 99.5% of cases in the Small group and in 90% in the Large group (PIVUS-Angio ≥ 0.50 mm occurred in 96% of case in the Small group and 80% in the Large group (PIVUS-Angio ≥ 0.50 in the Small group were: proximal or middle lesion site, vessel type (left anterior descending artery, diagonal and obtuse marginal branches) and female sex. An Δ_IVUS-Angio ≥ 1.0 mm occurred in 71% of cases in the Small group and in 49% in the Large group (PIVUS-Angio ≥ 1.0 mm in the Small group were: proximal or middle lesion site, female sex, and lesion length. Conclusions: A high percentage of vessels measuring ≤ 2.75 mm are large vessels with a high plaque burden. This condition is particularly prevalent in females, with lesions in the proximal or middle left anterior descending artery, and in obtuse marginal and diagonal branches.