Current and emerging catheter technologies for percutaneous transluminal coronary angioplasty Ponangi Udaya Prashant CARE Hospitals, Banjara Hills, Hyderabad, India Abstract: Appropriate guide catheter selection is a paramount requirement for successful angioplasty of complex coronary artery lesions. When choosing an appropriate guide catheter, the diameter and shape of the guide are the most important factors to be considered, and depend on the anatomy of the coronary artery and backup support required to cross the obstructive lesion. In turn, backup support of the guide catheter depends on the size and terminal shape of the guide rather than the route of intervention chosen and can be expressed mathematically. Many radial route-specific guide catheters have been developed by introducing extratertiary curves and angles to previous existing femoral guides. Backup support can be enhanced by various maneuvers and innovations like the “mother-child” technique. Computer-aided aortogram analysis can help in choosing the right catheter for anomalous coronary arteries. Newer catheter designs like increased lumen diameter ratios, total occlusion crossing support catheters, sheathless guides, and balloon-tipped guides are helping to overcome the shortcomings of antecedent guide catheters. Keywords: guide catheters, backup support, radial angioplasty, anomalous coronary arteries, Ikari catheter