A meta-analysis of first-generation drug-eluting vs bare-metal stents for coronary chronic total occlusion: Effect of length of follow-up on clinical outcome

Percutaneous Coronary Intervention in Chronic Total Occlusion

Percutaneous coronary intervention in chronic total occlusion is a rapidly evolving area, being considered the last frontier of interventional cardiology. In recent years, the development of new techniques and equipment, as well as the training of specialized personnel, increased their success rates, making it the most predictable procedure available. Although the number of randomized and controlled studies is still limited, results from large multicentered registries allow us to safely offer this intervention to patients, as another treatment option along with the optimized drug treatment and myocardial revascularization surgery. This review summarizes the last and most relevant publications in the subject in order to provide an overall view of the field’s current status.

Comparison between diabetic and non-diabetic patients after successful percutaneous coronary intervention for chronic total occlusions in the drug-eluting stent era

OBJECTIVE

Diabetes mellitus and chronic total occlusions are associated with unfavorable outcome after percutaneous coronary intervention. We sought to assess the clinical and angiographic outcomes of diabetic and non-diabetic patients who underwent successful percutaneous revascularization of chronic total occlusions with drug-eluting stents.

METHODS

Baseline clinical and angiographic characteristics, procedural details, nine-month angiographic follow-up and clinical events at 12 months were compared between 75 diabetic and 132 non-diabetic patients included in a clinical trial that randomized successful recanalization of chronic total occlusions to receive sirolimus- or everolimus-eluting stents.

RESULTS

In both diabetic and non-diabetic groups there was a favorable non-significantly different angiographic result at nine months, with low in-stent late loss (0.14±0.60 mm vs. 0.25±0.68 mm, p=0.305) and rates of binary restenosis (4.0% vs. 10.6%, p=0.180) and reocclusion (0.0% vs. 2.3%, p=0.334). During follow-up similar survival from death (97.3±1.9% vs. 99.2±0.8%, log-rank p=0.273), acute myocardial infarction (100.0±0.0% vs. 97.7±1.3%, log-rank p=0.192), target vessel revascularization (88.7±3.8% vs. 88.2±2.9%, log-rank p=0.899) and stent thrombosis (100.0±0.0% vs. 97.7±1.3%, log-rank p=0.192) was observed. Furthermore, the presence of more diffuse peripheral and coronary artery disease and higher frequency of calcified lesions in diabetic patients did not lead to significant differences in the approach (20.0% vs. 25.0% radial approach, p=0.413), strategy (6.7% vs. 3.8% retrograde strategy, p=0.353), total stent length (48.1±24.6 mm vs. 49.2±23.9 mm, p=0758) or contrast volume (261.3±116.4 ml vs. 297.4±135.9 ml, p=0.109) required for revascularization.

CONCLUSIONS

In the drug-eluting stent era, diabetic and non-diabetic patients have comparable favorable clinical and angiographic outcomes after successful percutaneous revascularization of chronic total occlusions.

Advances in the management of coronary chronic total occlusions

Chronic total occlusions (CTOs) have been called "the last frontier" of percutaneous coronary intervention (PCI) due to traditionally low success rates and high risk for restenosis and re-occlusion. Recent advances in equipment and crossing techniques have significantly increased CTO PCI success rates while maintaining low risk of complications. Specifically, the retrograde approach and controlled antegrade dissection and re-entry in conjunction with advanced guidewires and microcatheters have significantly improved procedural success rates. Moreover, the introduction of the "hybrid" approach has created a unified framework for operators to approach CTOs in a systematic and efficient fashion. Finally, drug-eluting stents, especially second generation, have improved long-term patency after CTO PCI.