Trial Outcomes & Findings for The Evaluation of Thrombogenicity in Patients Undergoing WATCHMAN Left Atrial Appendage Closure Trial (NCT NCT03040622)

Last Updated: 2024-03-29

Results Overview

Comparison of thrombin induced platelet-fibrin clot strength (TIP-FCS) as measured using thromboelastography (TEG-6s) between patients with and without device related thrombosis (DRT) assessed by transesophageal echocardiogram after left atrial appendage closure (LAAC) with Watchman device. TIP-FCS \>67mm has been associated with increased risk of hypercoagulability.

Recruitment status

COMPLETED

Target enrollment

35 participants

Primary outcome timeframe

Assessed at 1 year post implant.

Results posted on

2024-03-29

Participant Flow

Participant milestones

Participant milestones
Measure	Watchman Left Atrial Appendage Closure Patients implanted with WATCHMAN left atrial appendage closure device in a hospital setting
Overall Study STARTED	35
Overall Study COMPLETED	32
Overall Study NOT COMPLETED	3

Reasons for withdrawal

Reasons for withdrawal
Measure	Watchman Left Atrial Appendage Closure Patients implanted with WATCHMAN left atrial appendage closure device in a hospital setting
Overall Study unable to implant device	3

Baseline Characteristics

The Evaluation of Thrombogenicity in Patients Undergoing WATCHMAN Left Atrial Appendage Closure Trial

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Watchman Left Atrial Appendage Closure n=35 Participants WATCHMAN Left Atrial Appendage Closure: WATCHMAN Left Atrial Appendage Closure
Age, Continuous	76 years STANDARD_DEVIATION 8 • n=93 Participants
Sex: Female, Male Female	12 Participants n=93 Participants
Sex: Female, Male Male	23 Participants n=93 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=93 Participants
Race (NIH/OMB) Asian	1 Participants n=93 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=93 Participants
Race (NIH/OMB) Black or African American	0 Participants n=93 Participants
Race (NIH/OMB) White	34 Participants n=93 Participants
Race (NIH/OMB) More than one race	0 Participants n=93 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=93 Participants
Region of Enrollment United States	35 participants n=93 Participants

PRIMARY outcome

Timeframe: Assessed at 1 year post implant.

Population: The total group was separated into participants with and without DRT and TIP-FCS was compared between groups.

Outcome measures

Outcome measures
Measure	With Device Related Thrombosis n=3 Participants Patients with device related thrombosis within 1-year of implant	Without Device Related Thrombosis n=29 Participants Patients without device related thrombosis within 1-year of implant
Comparison of Thrombin Induced Platelet-fibrin Clot Strength (TIP-FCS) Between Patients With and Without Device Related Thrombosis (DRT) Assessed at 1-year of Watchman Implant	68.0 mm Standard Deviation 1.8	62.7 mm Standard Deviation 4.7

SECONDARY outcome

Timeframe: Assessed at 1 year post implant.

Population: The total group was separated into participants with and without DRT and FCS was compared between groups.

Comparison of fibrin clot strength (FCS) as measured using thromboelastography (TEG-6s) between patients with and without device related thrombosis (DRT) assessed by transesophageal echocardiogram after left atrial appendage closure (LAAC) with Watchman device. FCS \>32mm has been associated with increased risk of thrombosis.

Outcome measures

Outcome measures
Measure	With Device Related Thrombosis n=3 Participants Patients with device related thrombosis within 1-year of implant	Without Device Related Thrombosis n=29 Participants Patients without device related thrombosis within 1-year of implant
Comparison of Fibrin Clot Strength (FCS) Between Patients With and Without Device Related Thrombosis (DRT) Assessed at 1-year After Watchman Implant	35.6 mm Standard Deviation 6	24.4 mm Standard Deviation 6.6

SECONDARY outcome

Timeframe: Assessed at 1 year post implant

Comparison of D-dimer levels as measured using ACL TOP 300 hemostasis testing system between patients with and without device related thrombosis (DRT) assessed by transesophageal echocardiogram after left atrial appendage closure (LAAC) with Watchman device. D-dimer levels \>500ng/ml are associated with thrombo-embolic diseases.

Outcome measures

Outcome measures
Measure	With Device Related Thrombosis n=3 Participants Patients with device related thrombosis within 1-year of implant	Without Device Related Thrombosis n=29 Participants Patients without device related thrombosis within 1-year of implant
Comparison of D-dimer Levels Between Patients With and Without Device Related Thrombosis (DRT) Assessed at 1-year of Watchman Implant	1712 ng/ml Standard Deviation 2330	283 ng/ml Standard Deviation 213

SECONDARY outcome

Timeframe: within 1-year post implant

Number of participants with MACE \[all-cause death, systemic or pulmonary embolism, MI (myocardial ischemia) , TIA (transient ischemic attack) , stroke, DRT, and BARC bleeding (2,3, or 5) \] post Watchman implant..

Outcome measures

Outcome measures
Measure	With Device Related Thrombosis n=32 Participants Patients with device related thrombosis within 1-year of implant	Without Device Related Thrombosis Patients without device related thrombosis within 1-year of implant
Number of Participants With Major Adverse Clinical Events (MACE) Post Watchman Implant Device Related Thrombosis	3 Participants	—
Number of Participants With Major Adverse Clinical Events (MACE) Post Watchman Implant All-Cause Death	2 Participants	—
Number of Participants With Major Adverse Clinical Events (MACE) Post Watchman Implant BARC Bleeding	4 Participants	—
Number of Participants With Major Adverse Clinical Events (MACE) Post Watchman Implant Pulmonary Embolism	1 Participants	—
Number of Participants With Major Adverse Clinical Events (MACE) Post Watchman Implant TIA	1 Participants	—

Adverse Events

Watchman Left Atrial Appendage Closure

Serious events: 17 serious events

Other events: 0 other events

Deaths: 2 deaths

Serious adverse events

Serious adverse events
Measure	Watchman Left Atrial Appendage Closure n=32 participants at risk WATCHMAN Left Atrial Appendage Closure: WATCHMAN Left Atrial Appendage Closure
Vascular disorders Major Bleeding	12.5% 4/32 • Number of events 4 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
Respiratory, thoracic and mediastinal disorders Pulmonary Embolism	3.1% 1/32 • Number of events 1 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
Nervous system disorders TIA	3.1% 1/32 • Number of events 1 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
Blood and lymphatic system disorders Device Related Thrombosis	9.4% 3/32 • Number of events 3 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
Cardiac disorders Rehospitalization for atrial fibrillation with rapid ventricular rhythm	15.6% 5/32 • Number of events 5 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
Respiratory, thoracic and mediastinal disorders Rehospitalization for pneumonia	3.1% 1/32 • Number of events 1 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.
General disorders Rehospitalization-injury from a fall	6.2% 2/32 • Number of events 2 • 1 year Major adverse clinical outcomes monitored include: all-cause death, embolism (systemic or pulmonary), myocardial infarction, TIA, ischemic or hemorrhagic stroke, device related thrombosis, and major bleeding using the Academic Research Consortium (BARC) definition including BARC type 2, 3 or 5. DRT was defined as the presence of a persistent echogenic mobile mass attached to the WATCHMAN device confirmed by transesophageal echocardiography.

Other adverse events

Adverse event data not reported

Additional Information

Kevin Bliden

Inova Heart and Vascular Institute

Phone: 443-244-1497

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place