Extraplaque versus intraplaque tracking in chronic total occlusion percutaneous coronary intervention

Objective: To compare the clinical outcomes after extraplaque (EP) versus intraplaque (IP) tracking in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Background: The impact of modern dissection and reentry (DR) techniques on the long-term outcomes of CTO PCI remains controversial. Methods: We performed a systematic review and meta-analysis of studies that compared EP versus IP tracking in CTO PCI. Odds ratios (ORs) with 95% confidence intervals (CIs) are calculated using the Der-Simonian and Laird random-effects method. Results: Our meta-analysis included seven observational studies with 2982 patients. Patients who underwent EP tracking had significantly more complex CTOs with higher J-CTO score, longer lesion length, and more severe calcification and had significantly longer stented segments. During a median follow-up of 12 months (range 9–12 months), EP tracking was associated with a higher risk of major adverse cardiovascular events (MACE) (OR 1.50, 95% CI (1.10–2.06), p = 0.01) and target vessel revascularization (TVR) (OR 1.69, 95% CI (1.15–2.48), p = 0.01) compared with IP tracking. There was no difference in the incidence of all-cause death (OR 1.37, 95% CI (0.67–2.78), p = 0.39), myocardial infarction (MI) (OR 1.48, 95% CI (0.82–2.69), p = 0.20), stent thrombosis (OR 2.09, 95% CI (0.69–6.33), p = 0.19), or cardiac death (OR 1.10, 95% CI (0.39–3.15), p = 0.85) between IP and EP tracking. Conclusion: EP tracking is utilized in more complex CTOs and requires more stents. EP tracking is associated with a higher risk of MACE, driven by a higher risk of TVR at 1 year, but without an increased risk of death or MI compared with IP tracking. EP tracking is critically important for contemporary CTO PCI.