Important femoral vascular complications include access site hematoma, retroperitoneal hematoma, pseudoaneurysm, arteriovenous fistula, and arterial dissection and/or occlusion.252 The incidence of these vascular compli- cations in various reports generally ranges from 2% to 6% and has decreased with time.249,253 257 Factors associated with an increased risk of vascular complication include age 70 years, body surface area 1.6 m2 , emergency procedures, peripheral artery disease, periprocedural use of glycoprotein (GP) IIb/IIIa inhibitors, and female sex (if not corrected for body surface area).249,253,254,257,258 Ultrasound guidance has been used for femoral artery access to potentially decrease complications.259 As discussed in Section 5.11, vascular closure devices have not been clearly demonstrated to decrease vascular complication rates. Radial site access decreases the rate of access-related bleeding and complica- tions compared with femoral access.255,260 Loss of the radial pulse has been reported in 5% of radial procedures.261 Infrequent to rare complications occurring with the radial artery approach include compartment syndrome, pseudoan- eurysm ( 0.01%), and sterile abscess (occurring with previous-generation hydrophilic sheaths).262 Radial artery spasm may occur and treatment at times may be challenging. Local hematomas may occur from small-branch vessel hy- drophilic wire perforation or inexperience with wristband use. The risk of coronary perforation is approximately 0.2%, most commonly by wire perforation during PCI for CTO or by ablative or oversized devices during PCI of heavily diseased or tortuous coronary arteries.263 The risk of tampon- ade and management of the perforation varies with the type of Periprocedural bleeding is now recognized to be associated with subsequent mortality,265,266 and the avoidance of bleed- ing complications has become an important consideration in performing PCI. 