None listed
Conditions
Brief summary
This study first aims to evaluate whether there are differences between patients requiring stenting who have stable blockages in their coronary arteries versus those who present with unstable heart attacks. We hope to examine whether are difference in blood clotting (platelets in particular), release of inflammation markers (neutrophil-derived in particular), resistance to blood flow in the tiny capillaries of the heart muscle (microvascular resistance), and finally in morphology and composition of the culprit blockage or plaque as assessed by a technique named optical coherence tomography (OCT). In the unstable heart attack group in particular, we will also assess whether patients treated pre-procedurally with colchicine will demonstrate changes in these parameters compared to untreated controls. The purpose of the study is to identify whether colchicine could serve as a potential therapeutic option in these high-risk patients and improve outcomes by limiting adverse events such as further heart attack at the time of stenting (peri-procedural myocardial infarction). We hypothesise that levels of inflammation will be higher in unstable heart attack patients compared to patients with stable blockages, and that colchicine will attenuate the release of inflammatory products. We also hypothesise that in the unstable heart attack patients, there will be greater dysfunction in the microvessels of the heart and that this will correlate with inflammatory release and blood platelet adhesiveness, as well as with high-risk features of the culprit blockage/plaque as assessed by OCT.
Interventions
Patients will be prospectively recruited into this study, with approximately half with stable coronary disease and half with an acute coronary syndrome (ACS). In the ACS cohort, patients will be allocated in an alternating but non-randomised fashion to pre-procedural oral colchicine (1 mg then 0.5 mg one hour later) or no additional therapy. The intervention will be charted and delivered by study investigators, either on the ward or the cardiac day stay unit. In cardiac catheterisation laborator
Patients will be prospectively recruited into this study, with approximately half with stable coronary disease and half with an acute coronary syndrome (ACS). In the ACS cohort, patients will be allocated in an alternating but non-randomised fashion to pre-procedural oral colchicine (1 mg then 0.5 mg one hour later) or no additional therapy. The intervention will be charted and delivered by study investigators, either on the ward or the cardiac day stay unit. In cardiac catheterisation laboratory, we will isolate peripheral and coronary sinus blood inflammatory cytokines, microparticles and platelets from patients. We will also correlate microparticle release and platelet adhesiveness in ACS after stenting with plaque morphology and microvascular dysfunction, by: A. Measuring the IMR with a pressure wire in the coronary artery. B. Imaging of the atherosclerotic plaque with intracoronary imaging technology - optical coherence tomography (OCT) In the stable cohort, we will collect peripheral and coronary sinus blood samples and perform OCT and IMR analysis but there will be no intervention arm, similar to the control group in the ACS cohort.
Sponsors
The Heart Research Institute
Study design
Allocation
Non-randomised trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
21 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Inclusion Criteria: Patients (>21yrs) with a clinical need for cardiac catheterisation at Royal Prince Alfred Hospital will be invited to participate in the study.
Exclusion criteria
Exclusion criteria: Patients with greater than 50% stenosis in the left main coronary artery, cardiogenic shock or haemodynamic instability will be excluded from the study. Other exclusion criteria include age <21, pregnancy, those unable to make their own decisions, patients with moderate renal dysfunction (creatinine clearance <50 ml/min) or hepatic dysfunction (ALT [1.5 x upper limit of normal range); thrombocytopenia or leukopenia; pregnant or lactating women and women at risk of pregnancy. Patients already taking colchicine, those with evidence of active infection or inflammatory conditions that might be associated with markedly elevated hs-CRP levels in the blood (e.g., active rheumatoid arthritis) and those taking other anti-inflammatory therapies (e.g. corticosteroids) or strong CYP3A4 inhibitors will also be excluded.
Outcome results
None listed