BACKGROUND: Rupture of vulnerable atheromatous plaque in the carotid and coronary arteries often leads to stroke and heart attack respectively. The role of calcium deposition and its contribution to plaque stability is controversial. This study uses both an idealized and a patient-specific model to evaluate the effect of a calcium deposit on the stress distribution within an atheromatous plaque. METHODS: Using a finite-element method, structural analysis was performed on an idealized plaque model and the location of a calcium deposit within it was varied. In addition to the idealized model, in vivo high-resolution MR imaging was performed on 3 patients with carotid atheroma and stress distributions were generated. The individual plaques were chosen as they had calcium at varying locations with respect to the lumen and the fibrous cap. RESULTS: The predicted maximum stress was increased by 47.5% when the calcium deposit was located in the thin fibrous cap in the model when compared with that in a model without a deposit. The result of adding a calcium deposit either to the lipid core or remote from the lumen resulted in almost no increase in maximal stress. CONCLUSION: Calcification at the thin fibrous cap may result in high stress concentrations, ultimately increasing the risk of plaque rupture. Assessing the location of calcification may, in the future, aid in the risk stratification of patients with carotid stenosis. (c) 2007 S. Karger AG, Basel
BACKGROUND: Rupture of vulnerable atheromatous plaque in the carotid and coronary arteries often leads to stroke and heart attack respectively. The role of calcium deposition and its contribution to plaque stability is controversial. This study uses both an idealized and a patient-specific model to evaluate the effect of a calcium deposit on the stress distribution within an atheromatous plaque. METHODS: Using a finite-element method, structural analysis was performed on an idealized plaque model and the location of a calcium deposit within it was varied. In addition to the idealized model, in vivo high-resolution MR imaging was performed on 3 patients with carotid atheroma and stress distributions were generated. The individual plaques were chosen as they had calcium at varying locations with respect to the lumen and the fibrous cap. RESULTS: The predicted maximum stress was increased by 47.5% when the calcium deposit was located in the thin fibrous cap in the model when compared with that in a model without a deposit. The result of adding a calcium deposit either to the lipid core or remote from the lumen resulted in almost no increase in maximal stress. CONCLUSION:Calcification at the thin fibrous cap may result in high stress concentrations, ultimately increasing the risk of plaque rupture. Assessing the location of calcification may, in the future, aid in the risk stratification of patients with carotid stenosis. (c) 2007 S. Karger AG, Basel
Authors: Tetsuya Hoshino; Lori A Chow; Jeffrey J Hsu; Alice A Perlowski; Moeen Abedin; Jonathan Tobis; Yin Tintut; Ajit K Mal; William S Klug; Linda L Demer Journal: Am J Physiol Heart Circ Physiol Date: 2009-06-19 Impact factor: 4.733
Authors: Cheuk F Chan; Niall G Keenan; Sonia Nielles-Vallespin; Peter Gatehouse; Mary N Sheppard; Joseph J Boyle; Dudley J Pennell; David N Firmin Journal: J Cardiovasc Magn Reson Date: 2010-03-26 Impact factor: 5.364
Authors: Umar Sadat; Zhongzhao Teng; Victoria E Young; Chengcheng Zhu; Tjun Y Tang; Martin J Graves; Jonathan H Gillard Journal: Int J Cardiovasc Imaging Date: 2010-08-11 Impact factor: 2.357
Authors: Li Dong; William S Kerwin; Marina S Ferguson; Rui Li; Jinnan Wang; Huijun Chen; Gador Canton; Thomas S Hatsukami; Chun Yuan Journal: J Cardiovasc Magn Reson Date: 2009-12-15 Impact factor: 5.364