Guiding Principles for Chronic Total Occlusion Percutaneous Coronary Intervention
Authors: Brilakis Emmanouil S. , Mashayekhi Kambis , Tsuchikane Etsuo , Abi Rafeh Nidal , Alaswad Khaldoon , Araya Mario , Avran Alexandre , Azzalini Lorenzo , Babunashvili Avtandil M. , Bayani Baktash , Bhindi Ravinay , Boudou Nicolas , Boukhris Marouane , Božinović Nenad Ž. , Bryniarski Leszek , Bufe Alexander , Buller Christopher E. , Burke M. Nicholas , Büttner Heinz Joachim , Cardoso Pedro , Carlino Mauro , Christiansen Evald H. , Colombo Antonio , Croce Kevin , Damas de los Santos Felix , De Martini Tony , Dens Joseph , Di Mario Carlo , Dou Kefei , Egred Mohaned , ElGuindy Ahmed M. , Escaned Javier , Furkalo Sergey , Gagnor Andrea , Galassi Alfredo R. , Garbo Roberto , Ge Junbo , Goel Pravin Kumar , Goktekin Omer , Grancini Luca , Grantham J. Aaron , Hanratty Colm , Harb Stefan , Harding Scott A. , Henriques Jose P.S. , Hill Jonathan M. , Jaffer Farouc A. , Jang Yangsoo , Jussila Risto , Kalnins Artis , Kalyanasundaram Arun , Kandzari David E. , Kao Hsien-Li , Karmpaliotis Dimitri , Kassem Hussien Heshmat , Knaapen Paul , Kornowski Ran , Krestyaninov Oleg , Kumar A. V. Ganesh , Laanmets Peep , Lamelas Pablo , Lee Seung-Whan , Lefevre Thierry , Li Yue , Lim Soo-Teik , Lo Sidney , Lombardi William , McEntegart Margaret , Munawar Muhammad , Navarro Lecaro José Andrés , Ngo Hung M. , Nicholson William , Olivecrona Göran K. , Padilla Lucio , Postu Marin , Quadros Alexandre , Quesada Franklin Hanna , Prakasa Rao Vithala Surya , Reifart Nicolaus , Saghatelyan Meruzhan , Santiago Ricardo , Sianos George , Smith Elliot , C. Spratt James , Stone Gregg W. , Strange Julian W. , Tammam Khalid , Ungi Imre , Vo Minh , Vu Vu Hoang , Walsh Simon , Werner Gerald S. , Wollmuth Jason R. , Wu Eugene B. , Wyman R. Michael , Xu Bo , Yamane Masahisa , Ybarra Luiz F. , Yeh Robert W. , Zhang Qi , Rinfret Stephane 
Published: July 2019

Outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have improved because of advancements in equipment and techniques. With global collaboration and knowledge sharing, we have identified 7 common principles that are widely accepted as best practices for CTO-PCI.
1. Ischemic symptom improvement is the primary indication for CTO-PCI.
2. Dual coronary angiography and in-depth and structured review of the angiogram (and, if available, coronary computed tomography angiography) are key for planning and safely performing CTO-PCI.
3. Use of a microcatheter is essential for optimal guidewire manipulation and exchanges.
4. Antegrade wiring, antegrade dissection and reentry, and the retrograde approach are all complementary and necessary crossing strategies. Antegrade wiring is the most common initial technique, whereas retrograde and antegrade dissection and reentry are often required for more complex CTOs.
5. If the initially selected crossing strategy fails, efficient change to an alternative crossing technique increases the likelihood of eventual PCI success, shortens procedure time, and lowers radiation and contrast use.
6. Specific CTO-PCI expertise and volume and the availability of specialized equipment will increase the likelihood of crossing success and facilitate prevention and management of complications, such as perforation.
7. Meticulous attention to lesion preparation and stenting technique, often requiring intracoronary imaging, is required to ensure optimum stent expansion and minimize the risk of short- and long-term adverse events.
These principles have been widely adopted by experienced CTO-PCI operators and centers currently achieving high success and acceptable complication rates. Outcomes are less optimal at less experienced centers, highlighting the need for broader adoption of the aforementioned 7 guiding principles along with the development of additional simple and safe CTO crossing and revascularization strategies through ongoing research, education, and training.