None listed
Conditions
Brief summary
Aortic stenosis (AS) is the most common heart valve disease in the Western World. Transcatheter aortic valve implantation (TAVI) has substantially expanded the therapeutic options available to patients suffering from severe AS. However, despite the rapidly expanding clinical use of TAVI, patients remain at high risk for both thrombotic/clotting (e.g., stroke and valve thrombosis) and bleeding complications. Optimal preventative therapy is essential to minimise thrombosis without incurring excessive bleeding risk. Current recommendations for clot prevention in TAVI are extrapolated from heart vessel stunting (also known as percutaneous coronary intervention or PCI) data despite significant patient and procedural differences that likely result in different risk profiles. Until this is addressed, clinicians are left to advise and treat their patients without essential information. This observational study will recruit 40 patients undergoing TAVI, PCI and AVR to compare the clotting / bleeding changes that occur during the procedure. Blood will be sampled from each patient at 5 time points depending on the procedure. These blood samples will be assessed for the bleeding / clotting potential of the blood at that time using the latest blood clotting tests including ROTEMSigma, TEG6s, MultiPlate and various other specialised laboratory tests.
Interventions
In addition to routine clinical care, eligible consenting participants will be agreeing to the following:
1. access to their medical records for:
a) the completion of standardised data collection forms to identify pre-existing risk factors for thrombosis, bleeding or vascular disease, and to assign surgical-risk scores; and,
b) for the completion of standardised procedural record considering all aspects of the procedure with implications for coagulation;
2. Collection of blood samples at proce
In addition to routine clinical care, eligible consenting participants will be agreeing to the following: 1. access to their medical records for: a) the completion of standardised data collection forms to identify pre-existing risk factors for thrombosis, bleeding or vascular disease, and to assign surgical-risk scores; and, b) for the completion of standardised procedural record considering all aspects of the procedure with implications for coagulation; 2. Collection of blood samples at procedure-specific pre-specified timepoints at 5 occasions prior to, during and following the procedure. These samples will be processed for: a) point of care coagulation tests (comprising: ROTEMSigma, TEG6s, activated clotting time and Multiple analysers); b) standard laboratory testing (comprising: full blood count, coagulation tests [PT/INR, aPTT, direct fibrinogen], anti-xa assay) c) processing to, storage and transport of platelet poor plasma for specialised coagulation tests
Sponsors
St. Andrew's War Memorial Hospital
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1) Informed consent for participation; 2) Either: i) severe aortic stenosis (aortic valve area <0.8cm2, mean aortic valve gradient >40mmHg or peak jet velocity >4m/s); AND planned management with either a TF-TAVI or isolated AVR; OR, ii) Non-ST elevation myocardial infarction (new ischaemic ECG criteria, troponin > upper limit of normal, clinical symptoms); AND planned management with elective PCI; 3) Stable haemoglobin > 100g/l; 4) Non-emergency procedure; 5) Preserved ejection fraction (>50%).
Exclusion criteria
1) Lack of capacity to consent for him or herself; 2) Medications known to: i) interact with coagulation assays; or ii) have a known or suspected prothrombotic or coagulopathic action that cannot be corrected for by the analysers used for point of care coagulation testing; 3) Known or suspected bleeding or clotting disorders; 4) Severe liver, renal, respiratory or psychiatric disease (including substance abuse); 5) Enrolled in another study with a non-standard treatment intervention.
Outcome results
None listed