An observational study in Atrial Fibrillation and Thrombotic Risk, sponsored by University of Michigan. Not yet recruiting. Open to participants aged 80 Years and older. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by University of Michigan · Observational
The goal of this observational study is to learn about the effects of antiplatelet drugs on patients over the age of 80 with atrial fibrillation. The main question it aims to answer is:
-Is platelet reactivity effectively controlled in patients over the age of 80 diagnosed with atrial fibrillation following the Watchman procedure.
Cardiovascular disease remains the leading cause of death and the risk for morbidity and mortality due to cardiovascular disease is thought to increases with age. Platelets play a key role in cardiovascular disease as their activation is essential for the formation of an arterial thrombus, the precursor to myocardial infarction and stroke. Additionally, thrombosis has been shown to be linked to cardiac pathologies including atrial fibrillation. The link between optimal prevention of thrombosis and limiting the risk associated with increased bleeding has not been fully elucidated. Hence, our understanding of the prothrombotic state of the platelet and thrombotic risk in people over the age of 80 is not well understood. In this study, we evaluate the prothrombotic state of the platelets in patients in the cardiovascular clinic over the age of 80 diagnosed with atrial fibrillation who are taking antiplatelet medications to determine the benefits of these interventions in prevention of thrombotic events, propagation of the risk for atrial fibrillation, and bleeding
4,009 studies on the registry are indexed under Atrial Fibrillation; 961 are open to participants now.
This study's planned enrollment of 50 is below the median of 300 across 1,400 observational studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →University of Michigan is the lead sponsor of 1,506 studies on the registry; 192 are open to participants now.
Of its 169 completed or terminated interventional studies of FDA-regulated products, 133 (79%) have results posted.
Counted across the registry records on this site, refreshed daily.
The study population consists of patients over the age of 80 who have been diagnosed with atrial fibrillation and will receive the Watchman Procedure and receive antiplatelet drugs following procedure.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Patients over the age of 80 diagnosed with atrial fibrillation receiving ether aspirin alone or aspirin and clopidogrel
Platelet reactivity
platelet reactivity will be measured before and after antiplatelet treatment in patients over 80. Outcomes will include 1) platelet aggregation, 2) integrin activation, 3) alpha and dense granule secretion, 4) T-TAS activation, and 5) TEG.
Time frame: blood draw will occur prior to Watchman procedure and antiplatelet administration and 90 days following Watchman procedure while patients are taking antiplatelet drugs
No study locations are listed for this record.
Plan to share: No — IPD information will be made available on a request basis and determination will be made with HIPAA policies being taken into consideration and the treating physician.
No publications or documents are linked to this record.
Start is estimated for Nov 2026; primary completion for Aug 2028, 21 months later.
Of 550 non-industry observational studies under Atrial Fibrillation, half reached primary completion within 46 months of starting (the median), counting those still running; a quarter within 25 and three quarters within 91. This study's planned 21 months is below that.
Counting every sponsor, half of 698 studies reached it within 38 months; a quarter within 22 and three quarters within 76.
Start moved twice since we started tracking on Sep 25, 2026: Aug 2026 → Nov 2026, last on Nov 9, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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