Background:Calcification is an important component of the atherosclerotic plaque. It represents an important sequala of coronary atherosclerosis generally associated with disease of long duration. Calcified coronary lesions carry the risk of supoptimal stent expansion. A pre-interventional IVUS feature has an impact on management plan through detection and quantification of calcific patterns in the vessel wall.Aim of work:The aim of this work is to evaluate the acute results of stenting calcified coronary lesions, deployed at appropriate pressure that ensure optimal stent expansion by quantitative coronary angiography, and its relation to calcium severity, distribution and percent lesion calcium length.Methodology:Thirty native fluoroscopically calcified coronary lesions in 24 patients were studied with mean age of 52 6.4 years. All lesions were stented and studied with intravascular ultrasound (IVUS) before and after intervention. According to pre-interventional IVUS study, lesions were classified into two groups according to the degree of circumferential calcification (>180o or <180o) and according to calcium distribution (superficial or deep). Studying the correlation of the estimated percent lesion calcium length with different parameters of stent expansion was also done.Results:According to the extent of circumferential calcium, the final angiographic percent diamater stenosis and the final IVUS corrected percent area stenosis were significantly lower in lesion group with calcium arc <180o (10.5 7.3 vs 16.6 8.6, P= 0.047) and (46.2 8.4 vs 52.2 7.8, P= 0.05) respectively.According to calcium distribution, the final IVUS percent area stenosis was significantly lower in lesion group with deep calcium (12.7 9.8 vs 22.1 13.1, P= 0.034). stent expansion indices were significantly larger in lesion group with calcium arc <180o and also with group of deep calcium. The percent lesion calcium length had a significant negative correlation with stent expansion indices.Conclusion:Stenting calcified lesions is possible with low rate of clinical events. Optimal stent expansion was better achieved in lesions with calcium arc <180o, deep calcification and in lesion with decreased percent calcium length.