Incidence, location, magnitude, and clinical correlates of saphenous vein graft calcification: an intravascular ultrasound and angiographic study.

BACKGROUND

The pattern of saphenous vein graft (SVG) calcification before percutaneous intervention has not been studied.

METHODS AND RESULTS

We used diagnostic and preintervention intravascular ultrasound (IVUS) to determine the incidence and magnitude of SVG calcification in 334 SVG lesions in 274 consecutive patients. Calcium was found in 133 SVGs (40%). Calcium was uniformly distributed among 48 lesion sites (14%), 43 proximal references (13%), and 42 distal references (13%). Calcium was superficial in 20 (40%) and deep in 28 (60%). Over the entire length of the SVGs, the maximum arc and length of calcium (in calcium-containing SVGs) averaged 174+/-107 degrees and 6.8+/-4.8 mm, respectively. In calcium-containing SVGs, lesion site arc and length of calcium measured 151+/-107 degrees and 4.1+/-3.7 mm, similar to the proximal and distal references (175+/-121 degrees and 4.0+/-2.3 mm and 177+/-121 degrees and 4.1+/-2.5 mm, respectively). Graft age (7.5+/-4.7 versus 10.5+/-4.7 years, P<0.0001), insulin-treated diabetes mellitus (40% versus 60%, P=0.02), and tobacco use (44% versus 55%, P=0.06) were clinical independent predictors of SVG calcification.

CONCLUSIONS

Sixty-five percent of calcium-containing SVGs had reference calcium in the absence of lesion calcium. Calcium was located primarily in SVG wall and not at the plaque. These data suggest that SVG calcium is not just part of lesion formation and maturation. SVG calcium occurred more commonly in older grafts, in insulin-treated diabetic patients, and in smokers.