J INVASIVE CARDIOL 2017;29(2):E28-E29.
Key words: chronic total occlusion, long-term outcomes
A large meta-analysis involving over 28,000 patients has shown that compared with failed procedures, successful chronic total occlusion percutaneous coronary interventions (CTO-PCIs) are associated with a lower risk of death, stroke, and coronary artery bypass grafting and less recurrent angina pectoris.1 Many other smaller studies exist showing a mortality benefit following CTO-PCI.2 There remains limited randomized controlled trials on long-term clinical outcomes after CTO-PCI. New techniques involving dissection of the subintimal space and reentry into the true lumen increase success rates in CTO-PCI. However, their longer-term safety and efficacy remain unknown and poorly studied.3 One of the criticisms of extensive dissection/reentry (subintimal tracking and reentry) has been that it requires stenting of long coronary segments and often sacrifices side branches, leading to poor long-term outcomes. At present, the goal of CTO-PCI is to achieve revascularization using limited dissection/reentry and allow side-branch preservation, ideally with short stent lengths. We present a case of double-lumen formation seen at 1 year post CTO-PCI using subintimal dissection reentry with late restoration of major side branches.
An 80-year-old man presented with Canadian Cardiovascular Society class 2 angina despite maximal tolerated medical therapy. His background included hypertension and a previous inferior myocardial infarction in 1991, which had been treated medically. He had a documented CTO of the right coronary artery on angiography in 2005. A myocardial sestamibi perfusion scan showed moderate inferior peri-infarctional ischemia. His echocardiogram confirmed an ejection fraction of 50% with inferior hypokinesis. Right ventricular function was normal. Work-up angiography confirmed a CTO commencing at the proximal right coronary artery (Figure 1A) with a long (>20 mm) segment of occlusion with the distal vessel being collateralized from the left coronary system. There was only moderate disease of the left coronary system involving the left anterior descending coronary artery.
Percutaneous coronary intervention was performed with dual femoral arterial access. The initial approach was to attempt antegrade dissection/reentry with a bailout retrograde approach using the reverse controlled antegrade and retrograde tracking (CART) strategy if required. Successful antegrade subintimal blunt dissection with the Crossboss system (Boston Scientific) was performed followed by reentry into the true lumen with the Stingray catheter (Boston Scientific) (Figure 1B). Two overlapping drug-eluting stents were placed from the proximal to the mid-vessel with a pleasing angiographic result (Figure 1C).
Post procedure, the patient’s angina resolved and he exercised regularly. He returned for repeat coronary angiography 1 year after CTO-PCI for investigation of an episode of atypical chest pain. Coronary angiography showed no change in appearance in his left coronary system. The two stents in his right coronary artery were widely patent, but there was evidence of formation of a double-barrel lumen. Of note, this had led to return of function and preservation of major side branches, in particular a large right ventricular branch (Figure 1D). Right ventricular function was normal on echocardiogram.
This case is unique in that it demonstrates that following antegrade dissection reentry and formation of a segment of stented subintimal false lumen, there may be late recruitment of major side branches and therefore maintenance of ventricular function. Long-term vessel healing and imaging data are emerging.4 More long-term data are needed following CTO dissection-reentry techniques, in particular regarding vessel healing, stent strut coverage, and late remodeling.
1. 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;115:1367-1375.
2. Pujadas S, Martin V, Rosselló X, et al. Improvement of myocardial function and perfusion after successful percutaneous revascularization in patients with chronic total coronary occlusion. Int J Cardiol. 2013;169:147-152.
3. Rinfret S, Ribeiro HB, Nguyen CM, et al. Dissection and re-entry techniques and longer-term outcomes following successful percutaneous coronary intervention of chronic total occlusion. Am J Cardiol. 2014;114:1354-1360. Epub 2014 Aug 12.
4. Sherbet DP, Christopoulos G, Karatasakis A, et al. Optical coherence tomography findings after chronic total occlusion interventions: insights from the “AngiographiC evaluation of the everolimus-eluting stent in chronic Total occlusions” (ACE-CTO) study (NCT01012869).Cardiovasc Revasc Med. 2016;17:444-449. Epub 2016 Apr 15.
From the Cardiology Department, St George Hospital, Sydney, Australia.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.
Manuscript submitted August 15, 2016, provisional acceptance given August 22, 2016, final version accepted August 29, 2016.
Address for correspondence: Dr James Roy, Cardiology Department, Level 1, St George Public Hospital, Gray Street, Kogarah NSW 2217 Australia. Email: email@example.com