10.3 Latest Devices for CTO Intervention: Do They Improve Outcomes and Change Indications?

These proceedings summarize the educational activity of the 17th Biennial Meeting of the International Andreas Gruentzig Society held January 30 to February 2, 2024 in Chiang Rai, Thailand.

Faculty Disclosures     Vendor Acknowledgments

2024 IAGS Summary Document

Statement of the problem or issue

The prevalence of chronic total occlusions (CTO) in all patients undergoing coronary angiography is approximately 15%. In patients with acute coronary syndromes, it increases to around 30-to-40%. In patients undergoing coronary angiography who have had previous coronary artery bypass surgery (CABG), the prevalence of a CTO is 50% or more. The benefit of reopening a CTO is quality of life for the patient. There are 4 studies of CTO PCI that demonstrate benefit for quality of life and other symptoms (Table 1).^1-4

Table 1. Benefits of CTO PCI.

The procedural risk for major adverse events in CTO PCI is approximately double that for non-CTO PCI, 1.6% compared to 0.8%.⁵ In a large, comprehensive review of CTO PCI from a decade ago, which included 18,000 patients in 65 studies, the most common complications were coronary perforation, MI, and contrast-induced acute kidney injury.⁶ In the large national registries, CTO PCI overall procedural success rates are approximately 75%, and for registries based at experienced CTO centers, procedural success rates are better at approximately 85%-90%. However, these procedural success rates are lower than success rates in non-CTO PCI, and they help explain why CTO PCI has not caught on more broadly and become a staple coronary procedure.

In terms of devices, there are a number of them available for use in CTO PCI; some are listed in Table 2.

Table 2. Devices for CTO PCI.

There are a few prospective single arm studies examining these devices. However, such studies are of questionable utility. What these devices do is make CTO PCI procedures more consistent, faster, and thereby possibly safer. There is no magic in the devices specifically. Especially when these devices are used as part of an algorithm, they seem to be associated with higher success rates.

Gaps in current knowledge

There are a number of knowledge gaps in CTO PCI. If we are not able to demonstrate a mortality benefit for CTO PCI, which has been almost impossible to do for any PCI except primary PCI for STEMI, then what other metrics can we examine? Several candidates for these alternative metrics where information gaps exist are listed in Table 3.

Table 3. Knowledge and information gaps in CTO PCI.

Possible solutions and future directions

Several important factors appear to have moved this field forward, and likely will continue to do so for the foreseeable future. These factors are listed in Table 4.

Table 4. Important factors driving the CTO PCI field forward.

Finally, the field needs to move forward from hypothesis generating studies to hypothesis testing studies. The available devices coupled with an algorithmic approach, employed by skilled operators at dedicated team-based centers, will be the next phase.

References

1. Olivari Z, Rubartelli P, Piscione F, et al. Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE). J Am Coll Cardiol. 2003;41(10):1672-1678. doi: 10.1016/s0735-1097(03)00312-7. PMID: 12767645.
2. Christakopoulos GE, Christopoulos G, Carlino M, et al. Meta-analysis of clinical outcomes of patients who underwent percutaneous coronary interventions for chronic total occlusions. Am J Cardiol. 2015;115(10):1367-1375. doi: 10.1016/j.amjcard.2015.02.038. PMID: 25784515.
3. Joyal D, Afilalo J, Rinfret S. Effectiveness of recanalization of chronic total occlusions: a systematic review and meta-analysis. Am Heart J. 2010;160(1):179-187. doi: 10.1016/j.ahj.2010.04.015. PMID: 20598990.
4. Bruckel JT, Jaffer FA, O'Brien C, Stone L, Pomerantsev E, Yeh RW. Angina severity, depression, and response to percutaneous revascularization in patients with chronic total occlusion of coronary arteries. J Invasive Cardiol. 2016;28(2):44-51. PMID: 26477043.
5. 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). JACC Cardiovasc Interv. 2015;8(2):245-253. doi: 10.1016/j.jcin.2014.08.014. PMID: 25700746.
6. Patel, V, Brayton, K, Tamayo, A. et al. Angiographic success and procedural complications in patients undergoing percutaneous coronary chronic total occlusion interventions: A weighted meta-analysis of 18,061 patients from 65 studies. JACC Cardiac Interv. 2013;6(2):128-136. doi:/10.1016/j.jcin.2012.10.011.