Raising the bar for competency in high-risk coronary procedures

Rhian E Davies

Rhian E Davies (University of Washington Medical Center, Seattle, USA) discusses a recent paper considering the importance of training in high-risk percutaneous coronary intervention (PCI) procedures, as well as a renewed interest in both the development of this skillset outside of fellowship and maintenance of competency.

The objective of our recent article in Catheterization and Cardiovascular Interventions, “Training in high-risk coronary procedures and interventions: Recommendations for core competencies,” was the desire to standardise the experience of fellowship training in high-risk interventions1. As fellows leave their respective interventional fellowships, a wide variation of skillsets exists. Therefore, the goal of a high-risk fellowship was to ensure operators interested in high-risk intervention would receive the full complement of skills to successfully perform appropriately indicated percutaneous coronary interventions (PCI) in a safe and effective manner with the ultimate desire to improve patient care and outcomes. Of note, these recommendations were developed from review of available data and input from a cohort of high-volume high-risk operators, proctors, high-risk fellowship directors, former and current high-risk fellows.

With the release of this article, there has been renewed interest in both the development of this skillset outside of fellowship and maintenance of competency. Importantly, this article only addresses the skillsets and volume necessary to attain competency during a dedicated coronary fellowship training year in addition to the conventional Accreditation Council for Graduate Medical Education (ACGME)-approved year. We acknowledge that several operators (including several of the authors) have developed successful programmes without this additional fellowship and that there are multiple ways to attain competency in high-risk intervention including a combination of courses, books, instructional videos and proctorship2–4. However, for a junior operator to safely tackle the complexity of these cases that are typically only performed by the most experienced operators, we felt that the bar needed to be set high.

Apart from procedural volume, maintaining competency is dependent on developing an infrastructure that supports the maintenance of skill and an operator’s desire for further growth.  Some components of a successful programme include administrative support, buy-in from colleagues, dedicated time, dedicated cath lab staff, and a referral network. Additionally, the field of interventional cardiology is rapidly evolving, therefore it is important to be engaged in mentorship, teaching, and research.

Numerous reports from databases such as the National Commissioning Data Repository (NCDR), demonstrate a clear association between improved outcomes, particularly for high-risk interventions, and higher operator procedural volume5–8. To produce outcomes exhibited in clinical trials and registries, it is imperative that operators have the procedural volume to develop and maintain a high-risk skillset. These recommendations were made based on available data to provide the best care for patients who are at higher risk of experiencing an adverse event but also potentially have the most to gain from high-risk intervention9.

In regard to our unprotected left main (ULM) recommendations, data suggests a difference in mortality based on an operator volume of 15 ULM PCI cases per year10. The DKCRUSHV trial which evaluated ULM with distal bifurcations required operators perform ≥300 PCIs per year for five years with at least 20 ULM PCIs per year11.

As target lesion revascularisation has been an ongoing challenge for PCI, it is imperative that operators are facile with both use and understanding of intravascular imaging. Imaging, more specifically intravascular ultrasound (IVUS), has been shown to change PCI strategy and reduce MACE12–16.

Chronic total occlusion (CTO) PCI is arguably the most challenging subset managed by high-risk coronary operators. While the CTO PCI success rates have been relatively stagnant at around 50‒60% for all-comers, the goal of additional training is to produce operators with the ability to achieve >80% success rates that have been demonstrated in CTO PCI registries6,17–22.  Although there is limited data on the learning curve of CTO PCI, there appears to be an inflection point at which improvements in technical success occurred around 120‒125 cases/CTO operator23.

Given it is more commonly encountered in the peri-procedural period with high-risk intervention, it is important that operators are well-versed in both institution of haemodynamic support and management of heart failure and cardiogenic shock.

While occurrence of complications should decrease with proficiency, complications may arise more frequently with high-risk interventions. Therefore, the ability to manage complications can contribute significantly to reduction in morbidity and mortality. However, it is possible that not all of the complications—including urgent pericardiocentesis, coil embolisation, fat embolisation and snaring—can be directly observed or managed during the course of a single year of training. We therefore emphasise the importance in developing algorithms to manage these conditions.  Occasionally, some of these skills can be learned in non-emergent situations—for example: coiling an unnecessary graft when competitive flow is present from a newly re-opened native coronary vessel.

One pathway to allow operators to develop a high-risk skillset is through a high-risk PCI fellowship.  Fellowship provides a safe environment that allows trainees high procedural volume, teaching and mentorship to attain competency in a shorter timeframe. It goes without being said that the field of nterventional cardiology opens the door to a lifelong learning opportunity with a personal overall goal of improving our skills in order to provide the best possible patient care.

I gratefully acknowledge all the co-authors who participated in this initiative. I would also like to give special thanks to Ajay Kirtane and William Lombardi for their mentorship.


  1. Davies RE., Prasad M., Alaswad K., et al. Training in high-risk coronary procedures and interventions: Recommendations for core competencies. Catheter Cardiovasc Interv 2020. Doi: 10.1002/ccd.29229.
  2. Riley RF., Henry TD., Kong JA., et al. A CHIP fellow’s transition into practice: Building a complex coronary therapeutics program. Catheter Cardiovasc Interv 2019:ccd.28599. Doi: 10.1002/ccd.28599.
  3. Riley RF. Complex, Higher-Risk, and Indicated PCI (CHIP) Fellowship: Putting Training Into Practice. J Am Coll Cardiol 2020:980–4. Doi: 10.1016/j.jacc.2020.01.025.
  4. Tajti P., Brilakis ES. Chronic Total Occlusion Percutaneous Coronary Intervention: Evidence and Controversies n.d. Doi: 10.1161/JAHA.117.006732.
  5. Fanaroff AC., Zakroysky P., Wojdyla D., et al. Relationship between Operator Volume and Long-Term Outcomes after Percutaneous Coronary Intervention: Report from the NCDR CathPCI Registry. Circulation 2019;139(4):458–72. Doi: 10.1161/CIRCULATIONAHA.117.033325.
  6. Brilakis ES., Banerjee S., Karmpaliotis D., et al. Procedural Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention: A Report From the NCDR (National Cardiovascular Data Registry). 2015.
  7. Beohar N., Kaltenbach LA., Wojdyla D., et al. Trends in Usage and Clinical Outcomes of Coronary Atherectomy: A Report from the National Cardiovascular Data Registry CathPCI Registry. Circ Cardiovasc Interv 2020;13(2). Doi: 10.1161/CIRCINTERVENTIONS.119.008239.
  8. Valle JA., Tamez H., Abbott JD., et al. Contemporary Use and Trends in Unprotected Left Main Coronary Artery Percutaneous Coronary Intervention in the United States: An Analysis of the National Cardiovascular Data Registry Research to Practice Initiative. JAMA Cardiol 2019;4(2):100–9. Doi: 10.1001/jamacardio.2018.4376.
  9. Kirtane AJ., Doshi D., Leon MB., et al. Treatment of higher-risk patients with an indication for revascularization. Circulation 2016;134(5):422–31. Doi: 10.1161/CIRCULATIONAHA.116.022061.
  10. Xu B., Redfors B., Yang Y., et al. Impact of Operator Experience and Volume on Outcomes After Left Main Coronary Artery Percutaneous Coronary Intervention. JACC Cardiovasc Interv 2016. Doi: 10.1016/j.jcin.2016.08.011.
  11. Chen SL., Zhang JJ., Han Y., et al. Double Kissing Crush Versus Provisional Stenting for Left Main Distal Bifurcation Lesions: DKCRUSH-V Randomized Trial. J Am Coll Cardiol 2017. Doi: 10.1016/j.jacc.2017.09.1066.
  12. Hong SJ., Mintz GS., Ahn CM., et al. Effect of Intravascular Ultrasound–Guided Drug-Eluting Stent Implantation: 5-Year Follow-Up of the IVUS-XPL Randomized Trial. JACC Cardiovasc Interv 2020;13(1):62–71. Doi: 10.1016/j.jcin.2019.09.033.
  13. Witzenbichler B., Maehara A., Weisz G., et al. Relationship between intravascular ultrasound guidance and clinical outcomes after drug-eluting stents: The assessment of dual antiplatelet therapy with drug-eluting stents (ADAPT-DES) study. Circulation 2014;129(4):463–70. Doi: 10.1161/CIRCULATIONAHA.113.003942.
  14. Elgendy IY., Mahmoud AN., Elgendy AY., Bavry AA. Outcomes with intravascular ultrasound-guided stent implantation. Circ Cardiovasc Interv 2016;9(4). Doi: 10.1161/CIRCINTERVENTIONS.116.003700.
  15. Zhang J., Gao X., Kan J., et al. Intravascular Ultrasound Versus Angiography-Guided Drug-Eluting Stent Implantation: The ULTIMATE Trial. J Am Coll Cardiol 2018;72(24):3126–37. Doi: 10.1016/j.jacc.2018.09.013.
  16. Choi KH., Song Y Bin., Lee JM., et al. Impact of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention on Long-Term Clinical Outcomes in Patients Undergoing Complex Procedures. JACC Cardiovasc Interv 2019;12(7):607–20. Doi: 10.1016/j.jcin.2019.01.227.
  17. Young MN., Secemsky EA., Kaltenbach LA., et al. Examining the Operator Learning Curve for Percutaneous Coronary Intervention of Chronic Total Occlusions: A Report from the National Cardiovascular Data Registry. Circ Cardiovasc Interv 2019;12(8):1–10. Doi: 10.1161/CIRCINTERVENTIONS.119.007877.
  18. Mashayekhi K., Nührenberg TG., Toma A., et al. A Randomized Trial to Assess Regional Left Ventricular Function After Stent Implantation in Chronic Total Occlusion. JACC Cardiovasc Interv 2018;11(19):1982–91. Doi: 10.1016/j.jcin.2018.05.041.
  19. Werner GS., Martin-Yuste V., Hildick-Smith D., et al. A randomized multicentre trial to compare revascularization with optimal medical therapy for the treatment of chronic total coronary occlusions. Eur Heart J 2018;39(26):2484–93. Doi: 10.1093/eurheartj/ehy220.
  20. Maeremans J., Walsh S., Knaapen P., et al. The Hybrid Algorithm for Treating Chronic Total Occlusions in Europe. J Am Coll Cardiol 2016;68(18):1958–70. Doi: 10.1016/j.jacc.2016.08.034.
  21. Sapontis J., Salisbury AC., Yeh RW., et al. Early Procedural and Health Status Outcomes After Chronic Total Occlusion Angioplasty. JACC Cardiovasc Interv 2017;10(15):1523–34. Doi: 10.1016/j.jcin.2017.05.065.
  22. Tajti P., Karmpaliotis D., Alaswad K., et al. The Hybrid Approach to Chronic Total Occlusion Percutaneous Coronary Intervention. JACC Cardiovasc Interv 2018;11(14):1325–35. Doi: 10.1016/j.jcin.2018.02.036.
  23. Thompson CA., Jayne JE., Robb JF., et al. Retrograde Techniques and the Impact of Operator Volume on Percutaneous Intervention for Coronary Chronic Total Occlusions. An Early U.S. Experience. JACC Cardiovasc Interv 2009;2(9):834–42. Doi: 10.1016/j.jcin.2009.05.022.



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