A Placebo-controlled Trial of Chronic Total Occlusion Percutaneous Coronary Intervention for the Relief of Stable Angina

Study Overview
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Brief Summary
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ORBITA-CTO Pilot is a double blinded randomised placebo-controlled trial comparing the effects of chronic total occlusion percutaneous coronary intervention versus placebo on symptoms of angina in patients with background optimal medical therapy.

Official Title
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ORBITA-CTO Pilot: A Comparison of the Impact of CTO PCI Versus Placebo on Angina in Patients With Background Optimal Medical Therapy - a Pilot Study

Conditions
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Chronic Total Occlusion of Coronary Artery, Stable Angina

Intervention / Treatment
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* Procedure: Percutaneous coronary intervention
* Procedure: Placebo percutaneous coronary intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ORBITA CTO will enrol patients who meet all 5 of the following criteria: Accepted for CTO PCI procedure by a specialist CTO operator. Patients with symptoms related to a single vessel CTO (≥3 months duration, or probable CTO where duration is unknown) in a vessel of at least 2.5mm diameter without angiographically significant (LMS ≥50%, LAD/Cx/RCA/Graft ≥70%, ≥2mm diameter) coronary artery stenosis in remaining non-CTO vessels. Symptoms are: a) Typical exertional angina defined as: i) constricting discomfort in the front of the chest or in the neck, jaw, shoulder or arm ii) precipitated by physical exertion iii) relieved by rest or nitrates within 5 minutes b) Angina symptoms at rest (including decubitus angina and post-prandial angina). c) Shortness of breath on exertion considered to be angina equivalent. Clinical evidence of ischaemia in CTO territory on dobutamine stress echocardiography, nuclear myocardial perfusion scan, stress perfusion CMR or PET). Evidence of viability: If left ventricular angiogram or echocardiogram demonstrates LV impairment or RWMA then viability must be demonstrated. J-CTO score ≤ 3. Exclusion Criteria: Acute coronary syndrome within 4 weeks. PCI to non-CTO lesion in prior 4 weeks as part of ACS or elective PCI. Non-revascularised clinically important non-CTO vessel. Proven ischaemia (invasive or non-invasive) in non-culprit territory. Contraindications to PCI or drug-eluting stent (DES) implantation. Inability to tolerate or contraindication to DAPT. Severe valvular heart disease. Severe chronic pulmonary disease (FEV1 <30% of predicted value). Severe musculoskeletal disease resulting in immobility. Life expectancy <2years. Pregnancy. Age <18years. Inability to consent.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Percutaneous coronary intervention<br>Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). | Procedure: Percutaneous coronary intervention<br>* Percutaneous coronary intervention using drug eluting stents and contemporary CTO PCI techniques on background of optimal medical therapy.<br>* Other names: Coronary angioplasty;|
| Placebo Comparator: Placebo percutaneous coronary intervention<br>Placebo procedure for chronic total occlusion (CTO). | Procedure: Placebo percutaneous coronary intervention<br>* Placebo percutaneous coronary intervention procedure on background of optimal medical therapy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in angina symptom ordinal scale score between groups | Change in angina symptom ordinal scale score between groups | 24 & 26 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physical limitation, angina frequency, angina stability, treatment satisfaction and quality of life scores as measured by the Seattle Angina Questionnaire (SAQ) | Physical limitation, angina frequency, angina stability, treatment satisfaction and quality of life scores as measured by the Seattle Angina Questionnaire (SAQ) | 24 & 26 weeks | 
| SAQ summary score | SAQ summary score | 24 & 26 weeks | 
| Quality of life as measured by EQ-5D-5L | Quality of life as measured by EQ-5D-5L | 24 & 26 weeks | 
| Change in Rose dyspnea scale | Change in Rose dyspnea scale | 24 & 26 weeks | 
| Change in peak VO2 and VO2 at AT | Change in peak VO2 and VO2 at AT | 24 weeks | 
| Fidelity of blinding using Bang's blinding index (BI) | Fidelity of blinding using Bang's blinding index (BI) | 24 weeks | 
| Protocol adherence | Proportion of participants adherent to allocated randomised treatment | 26 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Angina, Chronic total occlusion, Angioplasty