909-26 There are Gender-Related Differences in Vessel Size, but not In Target Lesion Plaque Composition: A Pre-Intervention Intravascular Ultrasound Study

Abstract

Pre-intervention intravascular ultrasound imaging was used to assess the presence of gender-related differences in 627 focal, significant (quantitative angiographic diameter stenosis = 67 ± 16%), de novo, native vessel lesions in 465 males and 162 females (ages 60 ± 12 yrs). Lesion site external elastic membrane (EEM), lumen, and plaque + media (P + M) cross-sectional areas and % cross-sectional narrowing (%CSN = P + M/EEM were compared to a proximal reference site (most normal looking cross-section within 10 mm of the lesion, but before major side branches). Females Males p Reference EEM area (mm 2 ) 17.8 ± 5.6 19.9 ± 7.0 0.0006 Reference lumen area (mm 2 ) 8.9 ± 3.2 9.8 ± 4.0 0.013 Reference P+ M area (mm 2 ) 6.8 ± 11.6 7.2 ± 14.3 NS Reference % CSN 48.5 ± 12.9 50.1 ± 12.1 NS Lesion EEM area (mm 2 ) 17.6 ± 5.8 20.1 ± 5.5 0.0098 Lesion lumen area (mm 2 1.8 ± 0.8 1.9 ± 1.1 NS Lesion P + M area (mm 2 ) 15.8 ± 5.7 17.7 ± 6.9 0.0097 Lesion % CSN 88.8 ± 6.2 89.7 ± 63 NS Lesion/Reference EEM area 1.04 ± 0.24 1.00 ± 0.21 NS Lesion/Reference P + M area 2.19 ± 1.14 2.02 ± 213 NS There were no gender-related differences in lesion eccentricity (maximum/minimum P + M thickness = 2.8 ± 2.6 vs 3.1 ± 2.6), lesion or reference site plaque composition (frequency of fibrocalcific plaque elements), arc of calcium (104 ± 117° vs 105 ± 106°), or calcium distribution (superficial vs deep). We Conclude: Pre-intervention intravascular ultrasound imaging failed to detect any qualitative differences in de novo target lesion plaque composition or distribution in females compared to males. Arteries were smaller in females (smaller reference lumen and EEM areas and smaller lesion site EEM areas). However, the extent of compensatory arterial remodeling was similar (no difference in reference site and lesion site %CSN or in lesion/reference EEM area). The reduced target lesion plaque cross-sectional area in females can be explained entirely by the the smaller arterial size (no difference in lesion/reference P + M area).