No abstract

Outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have improved because of advancements in equipment and techniques. With global collaboration and knowledge sharing, we have identified 7 common principles that are widely accepted as best practices for CTO-PCI.  1. Ischemic symptom improvement is the primary indication for CTO-PCI.  2. Dual coronary angiography and in-depth and structured review of the angiogram (and, if available, coronary computed tomography angiography) are key for planning and safely performing CTO-PCI.  3. Use of a microcatheter is essential for optimal guidewire manipulation and exchanges.  4. Antegrade wiring, antegrade dissection and reentry, and the retrograde approach are all complementary and necessary crossing strategies. Antegrade wiring is the most common initial technique, whereas retrograde and antegrade dissection and reentry are often required for more complex CTOs.  5. If the initially selected crossing strategy fails, efficient change to an alternative crossing technique increases the likelihood of eventual PCI success, shortens procedure time, and lowers radiation and contrast use.  6. Specific CTO-PCI expertise and volume and the availability of specialized equipment will increase the likelihood of crossing success and facilitate prevention and management of complications, such as perforation.  7. Meticulous attention to lesion preparation and stenting technique, often requiring intracoronary imaging, is required to ensure optimum stent expansion and minimize the risk of short- and long-term adverse events. These principles have been widely adopted by experienced CTO-PCI operators and centers currently achieving high success and acceptable complication rates. Outcomes are less optimal at less experienced centers, highlighting the need for broader adoption of the aforementioned 7 guiding principles along with the development of additional simple and safe CTO crossing and revascularization strategies through ongoing research, education, and training.

Although the hybrid chronic total occlusion (CTO) algorithm had many excellent recommendations, there has been infrequent adoption in the Asia Pacific region. The Asia Pacific CTO club propose an algorithm for case selection based on the Japan-CTO score and a new CTO algorithm, which is applicable globally. This algorithm allows for differing skill sets and equipment availability and contains practical teaching for CTO percutaneous coronary intervention. Similar to the hybrid algorithm there are 3 main questions that determine whether the primary approach is antegrade or retrograde: 1) is there proximal cap ambiguity; 2) is the distal vessel of poor quality; and 3) are there interventional collaterals present. In contrast to the hybrid algorithm occlusion length alone does not determine the choice of either a wire escalation strategy or a dissection re-entry strategy. Rather a combination of factors including ambiguity of the vessel course, severe calcification, tortuosity, length, and previous failure are used to determine this. The role of intravascular ultrasound-guided entry to overcome proximal cap ambiguity and the CrossBoss catheter in occlusive in-stent restenosis are highlighted in the algorithm. Both the parallel wire technique and dissection re-entry with the Stingray system have been included as options when the initial antegrade wire passage fails. Intravascular ultrasound-guided wiring along with limited subintimal tracking and re-entry are included as final options in the algorithm. Finally, the algorithm incorporates guidance on when to stop the procedure. It is hoped that this algorithm will serve as the basis for future CTO percutaneous coronary intervention proctoring and training.

AimsMetal absorbable scaffolds constitute a conceptually attractive alternative to polymeric scaffolds. Promising 6-month outcomes of a second-generation drug-eluting absorbable metal scaffold (DREAMS 2G), consisting of an absorbable magnesium scaffold backbone, have been reported. We assessed the 12-month safety and performance of this novel device.Methods and resultsThe prospective, international, multi-centre, first-in-man BIOSOLVE-II trial enrolled 123 patients with up to two de novo lesions with a reference diameter between 2.2 and 3.7 mm. All patients were scheduled for angiographic follow-up at 6 months, and—if subjects consented—at 12 months. Dual antiplatelet therapy was recommended for 6 months. Quantitative coronary angiography (QCA) parameters remained stable from 6 to 12 months [paired data of 42 patients: in-segment late lumen loss 0.20 ± 0.21 mm vs. 0.25 ± 0.22 mm, P = 0.117, Δ 0.05 ± 0.21 mm (95% CI: −0.01;0.12); in-scaffold late lumen loss 0.37 ± 0.25 mm vs. 0.39 ± 0.27 mm, P = 0.446, Δ 0.03 ± 0.22 (95% CI: −0.04;0.10), respectively]. Intravascular ultrasound and optical coherence tomography findings corroborated the QCA results. Target lesion failure occurred in four patients (3.4%), consisting of one death of unknown cause, one target-vessel myocardial infarction, and two clinically driven target lesion revascularization. No additional event occurred beyond the 6-month follow-up. During the entire follow-up of 12 months, none of the patients experienced a definite or probable scaffold thrombosis.ConclusionThe novel drug-eluting metal absorbable scaffold DREAMS 2G showed a continuous favourable safety profile up to 12 months and stable angiographic parameters between 6 and 12 months.ClinicalTrials.gov identifierNCT01960504.

We observed consistency of effects in Asian patients receiving ticagrelor and clopidogrel in the PLATO study. The relatively modest number of Asian patients in this analysis supports further investigation of larger cohorts to confirm our observations.