Chronic Total Occlusion of Coronary Artery

Objective of this study is to 1) analyze the clinical, anatomical and periprocedural differences of patients who underwent a procedure related to coronary CTO through the antergrade approach and retrograde approach; 2) analyze the success rate of the procedures and the incidence and patterns of complications; 3) compare and analyze long-term performances after the successful procedure; and 4) identify the independent factors that require a retrograde approach and the prognostic factor regarding long-term performances after use of each approach.

Study design Prospective randomized open labeled multicenter study Hypotheses 1. In asymptomatic patients with ≥ 10% of myocardial ischemia: PCI (Percutaneous Coronary Intervention) with latest generation of drug eluting stents is superior to optimal medical therapy in terms of relative reduction in MACCE (Major Adverse Cardiovascular and Cerebrovascular events). 2. In symptomatic patients with ≥ 5% of myocardial ischemia: PCI with latest generation of drug eluting stents is superior to optimal medical therapy (OMT) in terms of improved life quality measured as an increase of SAQ (Self Assessment Questionnaire) score of 8 points after 6 months. Inclusion Criteria * CTO in native coronary artery * Myocardial ischemia in a territory supplied by CTO assessed by nuclear imaging. * Age ≥18 yrs. * Able to provide written Informed consent and willing to comply with the specified follow-up contacts * Target artery ≥ 2.5 mm Prior to randomization all patients undergo 3 months of OMT. Subsequently the population will be divided into: Cohort A: Asymptomatic (CCS \< 2 and SAQ QoL \> 60) patients with myocardial ischemia (≥ 10% of LV) in a territory supplied by CTO Cohort B: Symptomatic patients (CCS class ≥ 2 and/or SAQ QoL score ≤ 60 after treating non CTO lesions and after OMT) with Myocardial ischemia (5% of LV) in a territory supplied a CTO Cohort C: patients enrolled but not randomized in cohort A or B Exclusion criteria (for both cohort A and B) * NSTEMI or STEMI within 1 month * Coronary anatomy not suitable for CTO-procedure * Coronary artery disease involving the left main/three-vessel disease with indication for CABG following heart team conference * Life expectancy \< 2 years * Severe chronic pulmonary disease (FEV1 \< 30 % of predicted value) * Contraindication to dual anti-platelet therapy * Pregnancy * eGFR \< 30 mL/min/1.73 m2 * In multi-vessel disease: if it is deemed unsafe to treat the non-CTO lesion first. * Severe valvular heart disease Primary endpoint Cohort A: Composite endpoint of MACCE (all-cause mortality, stroke, any myocardial infarction, clinically driven revascularization\*), hospitalization for heart failure or incidence of malignant arrhythmias. \*CCS class ≥ 2 and/or QoL score \< 60. Same criteria used as for allocation to Cohort B Cohort B: SAQ Quality of Life Assessment after 6 months. Number of patients 1,560 (1200 in cohort A/360 in cohort B Follow up time Cohort A: 5 years Cohort B: 6 months

The goal of this project is to provide an improvement in wire performance to expedite crossing difficult lesions in the coronary vasculature.

A chronic total occlusion (CTO) is present in 15-20% of patients who are referred for invasive coronary angiography. CTO Percutaneous Coronary Intervention (PCI) procedure success rates have increased over the years and can be as high as 90% when performed by high-volume CTO operators.Procedurally, excess calcification in the CTO anatomy is one factor which makes it difficult to complete the procedure or obtain ideal stent expansion. Excess calcification is best identified by Computed Tomography Coronary Angiography (CTCA) rather than invasive angiography. The investigators plan to retrospectively evaluate CTCA in patients who underwent CTO PCI and correlate calcification characteristics with CTO PCI outcomes and tools utilised for calcium modification.

Rationale: Randomized trials could not yet establish favourable outcomes of CTO PCI on hard endpoints such as ejection fraction or mortality, when compared to optimal medical therapy. However, patients after CTO PCI appeared to be more frequently free of angina complaints, but the aetiology behind this is not fully understood. The investigators hypothesize that PCI of the CTO in patients preselected with an ischemic threshold (\>12.5%) on cardiac imaging leads to a reduction of the ischemic burden and therefore an increased benefit on functional outcomes. Objective: Primary objective is to determine whether PCI of the CTO will yield a higher reduction of ischemia assessed by exercise myocardial perfusion SPECT-CT from baseline to 6-month follow-up compared to a control group. Secondary objectives are 1) to evaluate the effect of PCI of the CTO on improvement in functional status, infarct size and left ventricular function from baseline to follow-up compared to the control group; 2) to study the association between ischemia reduction and functional outcome and left ventricular function; 3) to assess the influence of the collateral flow index on the ischemic burden (reduction), functional status, infarct size and left ventricular (contractile) function (hibernation). Study design: open multicentre randomized trial Study population: 82 patients eligible for CTO PCI Intervention: CTO PCI Primary endpoint: ischemic burden assessed with exercise myocardial perfusion SPECT-CT from baseline to 6 months follow-up.

This study aims to evaluate the treatment of Chronic total occlusion (CTO) disease. Whether Intravascular Ultrasonography (IVUS) guiding the implantation of drug-eluting stents (DES) will provide better long-term clinical outcomes compared with conventional angiography

The purpose of this study is to establish a consensus of treatment strategy of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) through patient registry of PCI for CTO performed by Japanese certified operators.