Incidence, Location, Magnitude, and Clinical Correlates of Saphenous Vein Graft Calcification

Abstract

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 174Ϯ107°and 6.8Ϯ4.8 mm, respectively. In calcium-containing SVGs, lesion site arc and length of calcium measured 151Ϯ107°and 4.1Ϯ3.7 mm, similar to the proximal and distal references (175Ϯ121°and 4.0Ϯ2.3 mm and 177Ϯ121°and 4.1Ϯ2.5 mm, respectively). Graft age (7.5Ϯ4.7 versus 10.5Ϯ4.7 years, PϽ0.0001), insulin-treated diabetes mellitus (40% versus 60%, Pϭ0.02), and tobacco use (44% versus 55%, Pϭ0.06) 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.

Differential Changes of Aorta and Carotid Vasodilation in Type 2 Diabetic GK and OLETF Rats: Paradoxical Roles of Hyperglycemia and Insulin

“…Insulin administration also resulted in intima hyperplasia, especially subendothelial thickening that may impede NO diffusion into smooth muscle to induce relaxation. The insulin-induced intima hyperplasia was also found in type 1 diabetes after balloon injury in rats [33] and may be responsible for accelerated coronary restenosis in human beings [34, 35]. Thus, our findings are consistent with the above reports, suggesting the metabolic correction by insulin could result in an unintentional hyperinsulinemia and intima hyperplasia that can be detrimental to endothelial function and vascular atherosclerosis.…”

Optical Coherence Tomography of De Novo Lesions and In-Stent Restenosis in Coronary Saphenous Vein Grafts (OCTOPUS Study)

“…Calcification was more common in older SVG, consistent with the previous in vivo IVUS observations. 26 The observed tissue friability and the intimal tear within SVG were also seen in previous OCT studies on de novo SVG lesions responsible for ACS. 18 In comparison with de novo SVG lesions, ISR of SVG developed faster and the time from stent implantation to ISR was similar to that observed in native coronary arteries.…”

Osteoprotegerin is not associated with angiographic coronary calcification

“…This is not supported by our data, suggesting that the factors leading to calcification of human coronary plaques may not be fully explained by systemic OPG levels. Alternatively, it is possible that the relation between OPG and calcification is detected only at non-culprit lesion sites or via more sensitive methods such as intravascular ultrasound [25]. While this result is somewhat surprising, we note that our overall findings regarding OPG are consistent with prior studies in which higher OPG levels are associated with markers of clinical cardiovascular risk such as diabetes and more advanced age [26,27].…”