Aortic dissection is a rare complication (0.005%). Most of the dissections occur during guide catheter manipulation. Right coronary artery is more frequently involved. JR and AL are responsible for most of the aortic dissections. It is best to prevent this complication by ensuring the correct guide size, curvature and coaxial alignment. Always look for pressure, damping or ventricularization and give gentle contrast injections. Aortic dissection during PCI is detected by aortogram, bedside echocardiography, transesophageal echocardiography and CT scan. Dissection of aorta limited to the ipsilateral cusp or <4 mm from cusp can be treated by stenting and has good prognosis. Dissections which extend >4 mm from the cusp may require surgery and have a guarded prognosis. Management of hemodynamics and life-threatening arrhythmias is of prime importance.