Risk factors for periprocedural myocardial injury can be classified into patient related factors, lesion related factors and procedure related factors [Herrmann. J. Peri-procedural myocardial injury: 2005 update. Eur Heart J. 2005;26: 2493-2519]. Patient related factors include the extend of coronary artery disease (multivessel disease increases risk 1.3 to 1.8 fold), presence of systemic atherosclerosis, older age, comorbidities like renal failure, unstable angina and pre procedural CRP (C-reactive factor) elevation. The lesion related factors predicting peri procedural myocardial injury were restenotic lesions, SVG (saphenous vein graft) disease, eccentric lesions, greater plaque burden, higher thrombus burden, plaque rupture and presence of major side branches. Procedure related factors were threatened or acute vascular closure, distal embolisation, no reflow or slow reflow and need for directional coronary atherectomy. In general, more complex procedure would have higher incidence of periprocedural myocardial injury.