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Submassive and Massive Pulmonary Embolism Treatment With Ultrasound Accelerated Thrombolysis Therapy (SEATTLE II)

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ClinicalTrials.gov Identifier: NCT01513759
Recruitment Status : Completed
First Posted : January 20, 2012
Results First Posted : July 5, 2019
Last Update Posted : July 19, 2021
EKOS Corporation
Information provided by (Responsible Party):
Boston Scientific Corporation

Brief Summary:
The purpose of this study is to determine if the EKOS EkoSonic® Endovascular Device when used in conjunction with recombinant tissue plasminogen activator (t-PA) as a treatment for acute PE will decrease the ratio of right ventricle (RV) to left ventricle (LV) diameter within 48 =/- 6 hours in participants with massive or submassive PE.

Condition or disease Intervention/treatment Phase
Pulmonary Embolism Acute Pulmonary Embolism Sub-massive Pulmonary Embolism Massive Pulmonary Embolism Pulmonary Thromboembolism Drug: recombinant tissue plasminogen activator Device: EKOS EkoSonic Endovascular System Phase 3

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 150 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: A Prospective, Single-Arm, Multi-Center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE)
Actual Study Start Date : June 7, 2012
Actual Primary Completion Date : February 17, 2013
Actual Study Completion Date : February 17, 2013

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: EkoSonic® Endovascular System
Participants will receive a total of 24 milligrams (mg) of recombinant t-PA infusion, at an infusion rate of 1 milligrams/hour (mg/hr) per device (2 mg/hour for bilateral PE) delivered through the EkoSonic® Endovascular System. This regimen allows for a recombinant t-PA infusion time of 24 hours for one catheter and 12 hours for two catheters, respectively.
Drug: recombinant tissue plasminogen activator
Participants will receive 24 mg of r-tPA delivered via the EkoSonic Endovascular Device.
Other Names:
  • r-tPA
  • t-PA
  • Alteplase

Device: EKOS EkoSonic Endovascular System
24 mg of r-tPA will be delivered through the EkoSonic Endovascular System.
Other Names:
  • EkoSonic Endovascular Device
  • EkoSonic

Primary Outcome Measures :
  1. Change From Baseline in the Right Ventricle (RV) Diameter-to-Left Ventricle (LV) Diameter Ratio Within 48 +/- 6 Hours of Initiation of Therapy [ Time Frame: Baseline, within 48 +/- 6 hours of initiation of therapy ]
    Change from baseline in RV diameter/LV diameter ratio was determined by contrast-enhanced chest computed tomography (CT) within 48 +/- 6 hours after initiating ultrasound-accelerated catheter-directed fibrinolysis.

  2. Number of Participants With Major Bleeding [ Time Frame: From start of study drug infusion up to 72 hours ]
    Bleeding adverse events were graded (severe or life-threatening, moderate or mild bleeding) according to the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) classification. The participant incidence of major bleeding events was defined as GUSTO moderate and severe events occurring within 72 hours after starting the ultrasound-accelerated catheter-directed fibrinolysis procedure. Mild: Does not meet criteria for moderate or severe; Moderate: Requires transfusion - No hemodynamic compromise; and Severe: Bleeding causes hemodynamic compromise and required intervention or intracranial hemorrhage. A summary of serious and all other non-serious adverse events regardless of causality is located in the Reported Adverse Events module.

Secondary Outcome Measures :
  1. Change From Baseline in Pulmonary Artery Systolic Pressure at 48 Hours After Start of Therapy [ Time Frame: Baseline, Hour 48 after initiation of therapy ]
    Change in pulmonary artery systolic pressure was assessed by baseline right-heart catheterization compared with right-heart catheterization at the conclusion of ultrasound-accelerated catheter-directed fibrinolysis and estimated by post-procedure transthoracic echocardiography within 48 hours after initiating the procedure.

  2. Percentage of Participants With Symptomatic Recurrent Pulmonary Embolism (PE) [ Time Frame: Baseline up to Day 30 ]
    Percentage of participants with symptomatic recurrent PE up to 30 days following the conclusion of the ultrasound-accelerated catheter-directed fibrinolysis procedure, were reported with a Wilson score 95% confidence interval. A summary of serious and all other non-serious adverse events regardless of causality is located in the Reported Adverse Events module.

  3. Number of Participants Who Died Due to Any Cause [ Time Frame: Baseline up to Day 30 ]
    Number of participants who died due to any cause for up to 30 days following the conclusion of the ultrasound-accelerated catheter-directed fibrinolysis procedure, were reported.

  4. Number of Devices That Could Not be Successfully Used for Infusion [ Time Frame: Baseline up to Day 30 ]
    Technical complications associated with the use of the EkoSonic device was recorded during catheter placement in the pulmonary artery and during the infusion procedure.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Computed tomography (CT) evidence of proximal PE (filling defect in at least one main or segmental pulmonary artery)
  • PE symptom duration less than or equal to (<=)14 days
  • Informed consent can be obtained from participant or Legally Authorized Representative (LAR)
  • Massive PE (syncope, systemic arterial hypotension, cardiogenic shock, or resuscitated cardiac arrest) or
  • Submassive PE (RV diameter-to-LV diameter greater than or equal to [>=] 0.9 on contrast-enhanced chest CT)

Exclusion Criteria:

  • Stroke or transient ischemic attack (TIA), head trauma, or other active intracranial or intraspinal disease within one year
  • Recent (within one month) or active bleeding from a major organ
  • Hematocrit less than (<) 30 percent (%)
  • Platelets < 100 thousand/microliter (mcL)
  • International Normalized Ratio (INR) greater than (>) 3
  • Activated partial thromboplastin time (aPTT) >50 seconds on no anticoagulants
  • Major surgery within seven days of screening for study enrollment
  • Serum creatinine >2 milligrams/deciliter (mg/dL)
  • Clinician deems high-risk for catastrophic bleeding
  • History of heparin-induced thrombocytopenia (HIT)
  • Pregnancy
  • Catheter-based pharmacomechanical treatment for pulmonary embolism within 3 days of study enrollment
  • Systolic blood pressure less than 80 mm Hg despite vasopressor or inotropic support
  • Cardiac arrest (including pulseless electrical activity and asystole) requiring active cardiopulmonary resuscitation (CPR)
  • Evidence of irreversible neurological compromise
  • Life expectancy <30 days
  • Use of thrombolytics or glycoprotein IIb/IIIa antagonists within 3 days prior to inclusion in the study
  • Previous enrollment in the SEATTLE study

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01513759

Show Show 22 study locations
Sponsors and Collaborators
Boston Scientific Corporation
EKOS Corporation
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Principal Investigator: Narinder Bhalla, MD Baptist Health
Principal Investigator: William Kuo, MD Stanford Hospital and Clinics
Principal Investigator: Stephen K Liu, MD Memorial Medical Center - Modesto
Principal Investigator: Immad Sidiq, MD Hartford Hospital
Study Chair: Samuel Z Goldhaber, MD Brigham and Women's
Principal Investigator: Mark J Garcia, MD Christiana Hospital
Principal Investigator: Rohit Bhatheja, MD AdventHealth
Principal Investigator: Robert Kennedy, MD Holmes Regional Medical Center
Principal Investigator: Fakhir Elmasri, MD Lakeland Regional Medical Center
Principal Investigator: Barry S Weinstock, MD Orlando Regional Medical Center
Principal Investigator: Juan Ayerdi, MD Medical Center of Central Georgia
Principal Investigator: Nilesh Goswami, MD Prairie Heart Institute - St.John's Hospital
Principal Investigator: Kannan Natarajan, MD St Vincent's Hospital
Principal Investigator: Tod C Engelhardt, MD East Jefferson General Hospital
Principal Investigator: Mark Kumar, MD Overlook Medical Center
Principal Investigator: John Rundback, MD Holy Name Hospital
Principal Investigator: Jacob Cynamon, MD Montefiore Medical Center
Principal Investigator: Peter Soukas, MD The Miriam Hospital
Principal Investigator: Mohammad L Raja, MD Providence Memorial Hospital - Sierra Vista Hospital
Principal Investigator: Keith M Sterling, MD Inova Alexandria
Principal Investigator: John Gurley, MD University of Kentucky
Principal Investigator: Noah Jones, MD Mt. Carmel East
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: Boston Scientific Corporation
ClinicalTrials.gov Identifier: NCT01513759    
Other Study ID Numbers: EKOS 09
First Posted: January 20, 2012    Key Record Dates
Results First Posted: July 5, 2019
Last Update Posted: July 19, 2021
Last Verified: July 2021
Keywords provided by Boston Scientific Corporation:
catheter directed fibrinolysis
ultrasound accelerated fibrinolysis
recombinant t-PA
Additional relevant MeSH terms:
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Pulmonary Embolism
Embolism and Thrombosis
Vascular Diseases
Cardiovascular Diseases
Lung Diseases
Respiratory Tract Diseases
Tissue Plasminogen Activator
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action