Insights into the pathogenesis of vein graft disease: lessons from intravascular ultrasound

Table 1 Early adaptive changes and neointima formation in saphenous vein grafts

Study Reference	Grafts / Patients	Pre implantation to 1 month (mm²)				>12 months (mm²)
		Lumen	Wall Area	Vessel CSA	%wall area	Lumen	Plaque area	Wall Area	EEL area	Vessel CSA	% plaque area	%wall area
Nishioka et al 1996 [20]	43/42	16.5 ± 5.7	7.4 ± 2.1	23.9 ± 7.3	32.3 ± 7	8.9 ± 2.7	10.0 ± 5.3	15.2 ± 5.8	18.8 ± 7.5	24.0 ± 7.8	51 ± 10	63 ± 7
Ge et al 1999 [21]**	43/43								12.6 ± 4.0 – 19.0 ± 9.7		64.5 ± 15.5
Hong et al 1999 [22]**	104/93					12.0 ± 4.2 – 3.8 ± 1.9	7.2 ± 4.1 – 13.9 ± 4.9	10.0 ± 3.0 – 20.3 ± 6.5	16.7 ± .9 17.8 ± 6.1	20.8 ± 5.1 – 24.1 ± 7.8	30 ± 5 – 79 ± 9	45 ± 5 – 83 ± 7
Higuchi et al 2002τ [16]	47	16.2 ± 5.5	5.3 ± 2.0	21.6 ± 7.1	24.9 ± 5.0	12.8 ± 4.6		15.8 ± 5.2		28.8 ± 8.8		55.7 ± 6.8

**values represent range from reference segment to focal stenosis, τ angiographically normal vein. Vessel CSA, (cross sectional area) measured by tracing the outer border of the whole vein graft, Wall area, Vessel CSA minus lumen area. Percent wall area was calculated as the wall area divided by Vessel CSA. In situ veins do not have an external elastic membrane however; arterialized saphenous vein grafts develop a sonolucent zone, which has been reported to represent media. The EEL (external elastic membrane) area is measured by tracing the outer border of this sonolucent zone. Plaque area is calculated as external elastic membrane minus lumen area. Percent plaque area is calculated as plaque area divided by external elastic membrane area; this has also been called the plaque burden. Plaque burden and percent wall are closely correlated.

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