LAUSR

Although chronic total occlusions (CTOs) are a common coronary angiographic finding, with an incidence reaching >25%, a disproportionately smaller portion of patients are treated with percutaneous coronary intervention (PCI), comprising 8% of the overall PCI volume.1 There appear to be at least two important issues that are associated with the existing discrepancy between the occurrence of CTO and the rate of CTO PCI in contemporary clinical practice. First, percutaneous CTO recanalisation is often considered to be technically difficult, resource-demanding and time-demanding, with a complication rate exceeding that of a non-CTO PCI. However, recent advances in the interventional technique, both antegrade and retrograde, including the hybrid algorithm, have resulted in >90% procedural success rates, while being associated with a low occurrence of major complications, such as cardiac tamponade, myocardial infarction and death (all well below 1%).1 Second, the evidence base regarding clinical benefits of CTO PCI over medical therapy has largely been confined to observational data, stemming mainly from retrospective comparisons of clinical outcomes in patients with successful versus failed CTO PCI,1 whereas randomised studies evaluating the effects of PCI versus medical therapy for CTO have been scarce. Notwithstanding the currently insufficient randomised evidence base, the clinical appeal of CTO PCI seems to, at least in part, rest on the notion of achieving percutaneous complete revascularisation in patients with significant coronary artery disease as incomplete revascularisation has been linked to impaired prognosis.2 In their Heart manuscript, Elias et al 3 present long-term data of the hitherto only randomised controlled trial evaluating the effects of CTO PCI versus conservative management, published in a peer-review journal. Moreover, this was the first study to randomly investigate the value of PCI for a non-culprit CTO, …