Percutaneous coronary intervention or conservative therapy for chronic total coronary occlusions (CTOs)? Evidence from the ISCHEMIA trial

The management of chronic total coronary occlusions (CTOs) remains one of the most debated areas in interventional cardiology because of its technical complexity and the relatively high risk of procedural complications. Although the effectiveness of percutaneous coronary intervention for CTOs (CTO–PCI) in improving symptoms has been demonstrated, its impact on hard clinical outcomes remains controversial. The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA Trial) and the ISCHEMIA CTO sub-study provide important insights: in patients with stable coronary artery disease and moderate-to-severe ischaemia, an initial invasive strategy does not reduce cardiovascular mortality or myocardial infarction compared with optimized medical therapy. However, the trial was not designed to specifically assess the effectiveness of CTO–PCI, and only a minority of enrolled patients had a CTO, which was revascularized in only few cases. In addition, the ISCHEMIA trial excluded high-risk patients who are frequently encountered in everyday clinical practice, such as those with left main coronary artery disease, severe symptoms, or recent acute coronary syndromes. This article critically analyses the results of the ISCHEMIA Trial in the context of CTOs, comparing them with evidence from dedicated CTO–PCI studies, and proposes an integrated decision-making model based on symptom control, objective demonstration of inducible ischaemia and myocardial viability, multimodal imaging, and discussion within the Heart Team.