430 Pak J Med Sci 2008 Vol. 24 No. 3 www.pjms.com.pk Original Article PREDICTORS OF SIDE BRANCH OCCLUSION AND ITS EARLY COMPLICATIONS AFTER ANGIOPLASTY IN BIFURCATION LESIONS Ali Ghayemian 1 , Y. Nozari 2 , M. Safir 3 , Reza A. Mohammadpour 4 ABSTRACT Objective: Coronary angioplasty in bifurcation lesions has lower success rate and more complications than other lesions. We performed this study to define early complications of angioplasty in these lesions and to find the predictive factors of major side branch (more than 1mm) occlusion. Methodology: In this study, 104 consecutive patients with bifurcation lesion in a single center were evaluated. The side branches were classified based on diameter and morphology of the lesions. Results: In 41 (39.4%) patients side branch compromise (SBC) occurred. In patients with SBC 34.1% had chest pain and in 3 (2.9%) patients non–Q wave myocardial infarction (MI) occurred, all after SBC. The incidence of non-Q wave MI after SBC was 7.3%. The probability of SBC in patients with ostial lesion of more than 50% was significantly higher (p=0.021) than patients without such a lesion. Also, if the main branch lesion was more than 80%; SBC was significantly higher (p=0.011) than patients without such lesions. Using multiple logistic regression analysis, only more than 80% stenosis in the main branch had significant relation with SBC [OR: 5.91; 95% CI (1.28-27.3); p=0.023]. SBC had no statistically significant relation with age, sex, length of the lesion and ejection fraction. Conclusion: In angioplasty of bifurcation lesions, the presence of more than 80% stenosis of main branch increases the probability of SBC and more classifications may be unnecessary. KEY WORDS: Coronary angioplasty, Bifurcation lesions, Side branch occlusion. Pak J Med Sci April - June 2008 (Part-II) Vol. 24 No. 3 430-435 How to cite this article: Ghayemian A, Nozari Y, Safir M, Mohammadpour RA. Predictors of side branch occlusion and its early complications after angioplasty in bifurcation lesions. Pak J Med Sci 2008;24(3):430-5. Correspondence Dr. Reza Ali Mohammadpour, Assistant Prof. of Biostatistics, Department of Biostatistics, Mazandaran University of Medical Sciences, 18 th km Khazarabad Street, Health Faculty, PO Box: 48175-1553, Sari, Iran. E-mail: mohammadpour2002@yahoo.com * Received for Publication: January 5, 2008 * Accepted: May 1, 2008 INTRODUCTION Bifurcation coronary lesions are prone to development of atherosclerosis because of tur- bulent flow. These lesions comprise about 15% of coronary interventions. 1-3 The risk of side branch occlusion is a well known complica- tion of coronary intervention and has been reported to be about 12-41 percent. 4,5 Although occlusion of small side branches is well toler- ated, 1,6-8 occlusion of larger side branches may cause more serious complications, 6,7 therefore different approaches are used for treating these lesions. 2,9 Drug eluting stents (DES) have