A Phase 4 interventional study of Anticoagulation with heparin and EkoSonicTM Endovascular System in Pulmonary Embolism, sponsored by Boston Scientific Corporation. Active, not recruiting at 60 sites in 9 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-07-01.
Sponsored by Boston Scientific Corporation · Phase 4, Interventional, and Treatment
There are many available treatments for pulmonary embolism (PE), but the best treatment for this condition is not known. The HI-PEITHO study will compare two treatment options that are both available on the market for the treatment of PE.
Patients will be randomized 1:1 to receive either blood thinners (anticoagulation) or blood thinners (anticoagulation) in combination with a device called the EkoSonicTM Endovascular device to dissolve blood clots. Patients will be followed for 12 months after randomization and have assessments while in the hospital as well as at 7 days, 30 days, 6 months and 12 months after randomization. The study will try to find out if one of these treatments is better than the other at reducing the risk of death and other serious problems.
This study will assess whether ultrasound-facilitated, catheter-directed thrombolysis and standard anticoagulation are associated with a significant reduction in the composite outcome of pulmonary embolism (PE)-related mortality, cardiorespiratory decompensation or collapse, or nonfatal symptomatic and objectively confirmed recurrence of PE compared to anticoagulation alone within seven days of randomization
The HI-PEITHO study has been designed to address the important gaps in clinical evidence by comparing the clinical benefit of the ultrasound-facilitated local delivery of a low dose thrombolytic agent and anticoagulation with those of anticoagulation alone in patients with intermediate-high risk PE at a higher estimated risk of early decompensation based on clinical parameters at presentation.
This study has a focus on improving the safety of thrombolysis and advancing the concept of intermediate-high risk and the PE severity criteria, to better identify patients who may clinically benefit from thrombolysis.
The results of this study will contribute further evidence to the existing data on the treatment and outcomes of acute, intermediate-high risk PE and provide controlled data related to catheter-based interventions.
Data will be entered by the site into an electronic database. The database will include data checks to compare data entered into the database against predefined rules for ranges and consistency with other data fields in the database.
Site monitoring will take place with source data verification to assess the accuracy and completeness of registry data by comparing the data to medical records and study assessments.
739 studies on the registry are indexed under Pulmonary Embolism; 159 are open to participants now.
This study's enrollment of 544 is above the median of 150 across 381 interventional studies indexed under Pulmonary Embolism.
Browse Pulmonary Embolism studies →Boston Scientific Corporation is the lead sponsor of 517 studies on the registry; 38 are open to participants now.
Of its 64 completed or terminated interventional studies of FDA-regulated products, 56 (88%) have results posted.
Counted across the registry records on this site, refreshed daily.
Elevated risk of early death/hemodynamic collapse, indicated by at least two of the following new-onset clinical criteria:
Exclusion Criteria:
Hemodynamic instability*, i.e. at least one of the following present:
Low-molecular weight heparin (LMWH) or unfractionated heparin (UFH)
Drug: Anticoagulation with heparin
Low-molecular weight heparin (LMWH) or unfractionated heparin (UFH) and EkoSonicTM Endovascular System \[ultrasound-facilitated catheter-directed delivery of thrombolytic: 2 mg bolus/catheter + 1 mg/hour/catheter for 7 hours (total of 9 or 18 mg\]
Drug: Anticoagulation with heparin · Device: EkoSonicTM Endovascular System
Low-molecular weight heparin (LMWH) or unfractionated heparin (UFH)
Also known as: heparin, LMWH, UFH, anticoag, antiplatelet
EkoSonicTM Endovascular System \[ultrasound-facilitated catheter-directed delivery of thrombolytic: 2 mg bolus/catheter + 1 mg/hour/catheter for 7 hours (total of 9 or 18 mg\]
Also known as: EKOS, USCDT, CDT, thrombolysis, fibrinolysis
PE-related mortality
death resulting from PE
Time frame: Within seven days of randomization
PE recurrence
nonfatal symptomatic and objectively confirmed recurrence of PE
Time frame: Within seven days of randomization
Cardiorespiratory decompensation or collapse
Cardiorespiratory collapse or decompensation is defined as at least one of the following criteria: 1. cardiac arrest or need for CPR at any time between randomization and day 7; 2. signs of shock: new-onset persistent arterial hypotension (systolic blood pressure (SBP) below 90 mmHg or SBP drop by at least 40 mm Hg, over at least 15 minutes and despite an adequate volume status; or need for vasopressors to maintain SBP of at least 90 mmHg), accompanied by end-organ hypoperfusion (altered mental status; oliguria/anuria; or increased serum lactate) at any time between randomization and day 7; 3. placement on extracorporeal membrane oxygenation (ECMO) at any time between randomization and day 7; 4. intubation, or initiation of noninvasive mechanical ventilation at any time between randomization and day 7; 5. National Early Warning Score (NEWS) of 9 or higher, between 24 hours and 7 days after randomization, confirmed on consecutive measurements taken twice, 15 minutes apart.
Time frame: Within seven days of randomization
Change in the RV-to-LV diameter ratio as measured by echocardiography
Time frame: Between baseline and 48±6 hours
PE-related death
Death cause by pulmonary embolism (PE)
Time frame: Within 7 days
Cardiorespiratory decompensation
Time frame: Within 7 days
Placement on ECMO or mechanical ventilation
Time frame: Within 7 days
GUSTO major (moderate and severe) bleeding
Major bleeding will be adjudicated according to the GUSTO criteria: 1. GUSTO severe or life-threatening bleeding: A bleeding episode that leads to hemodynamic compromise requiring emergency intervention (such as replacement of fluid and/or blood products, inotropic support, or surgical treatment), or is life-threatening or fatal. 2. GUSTO moderate bleeding (a bleeding episode requiring blood transfusion(s), but which is not deemed life-threatening and does not lead to hemodynamic compromise requiring emergency fluid replacement, inotropic support, or interventional treatment) .
Time frame: Within 7 days
International Society on Thrombosis and Hemostasis (ISTH) major bleeding
Major bleeding will also be adjudicated according to the ISTH criteria: 1. Fatal bleeding and/or 2. Symptomatic bleeding in a critical area or organ (intracranial, intraspinal, intraocular, retroperitoneal, intra-articular or pericardial, or intramuscular with compartment syndrome) and/or 3. Bleeding causing a fall in hemoglobin level of 20 g/L (2 g/dL) or more, or leading to transfusion of two or more units of whole blood or red blood cells.
Time frame: Within 7 days, 30 days, and 6 months
Ischemic or hemorrhagic stroke
Time frame: Within 7 days and 30 days
All-cause mortality
Death due to any cause
Time frame: Within 7 days, 30 days, 6 months, and 12 months
Serious adverse events
Time frame: Within 30 days
All-cause mortality, cardiorespiratory collapse or recurrence of PE
Death due to any cause, Cardiorespiratory collapse or decompensation should fulfill at least one of the following criteria: 1. cardiac arrest or need for CPR at any time between randomization and day 7; 2. signs of shock: new-onset persistent arterial hypotension (SBP below 90 mmHg or SBP drop by at least 40 mmHg over at least 15 minutes, and despite an adequate filling status; or need for vasopressors to maintain SBP of at least 90 mmHg), accompanied by end-organ hypoperfusion (altered mental status; oliguria/anuria; or increased serum lactate) at any time between randomization and day 7; 3. placement on ECMO at any time between randomization and day 7; 4. intubation, or initiation of non-invasive mechanical ventilation at any time between randomization and day 7; 5. National Early Warning Score (NEWS) of 9 or higher, between 24 hours and 7 days after randomization, confirmed on consecutive measurements, taken twice.
Time frame: Within 30 days
Symptomatic PE recurrence
Time frame: Within 30 days and 6 months
Change from baseline in RV dysfunction on echocardiography
Right ventricle to left ventricle end diastolic diameter ratio (RV/LV)
Time frame: 6 months
Duration of hospitalization for the index PE event
Time from admission to discharge from hospital
Time frame: Within 30 days
Duration of stay at the intensive, intermediate or coronary care unit during hospitalization for the index PE event
Time from admission to discharge from ICU, intermediate, or ICC
Time frame: Within 30 days
Functional status as measured by World Health Organization (WHO) functional class
The World Health Organization (WHO) Functional Class assessment is a system for assessing the severity of dyspnea in patients with pulmonary hypertension. Subjects will be classified as Class 1-4 at time points throughout their participation in the study.
Time frame: Up to 7 days, 30 days, 6 and 12 months
Functional status as measured by 6-Minute Walk Test (6MWT)
The 6MWT measures the distance a patient can walk on a flat surface in a period of 6 minutes. A 100 meter distance is measured in a hallway and the patient is asked to walk quickly as many laps as they can over the course of the timed test. The total distance is measured. The patient's baseline vitals and symptoms are compared to their condition at the completion of the test.
Time frame: 30 days, 6 and 12 months
Functional status as measured by Post-Venous Thromboembolism Functional Status (PVFS) scale
The Post-Venous Thromboembolism (VTE) Functional Status (PVFS) scale focuses on relevant aspects of daily life during follow-up after a venous thromboembolic event. The scale is neither intended to solely focus on VTE-associated functional limitations nor to diagnose post-VTE syndrome. In contrast, the scale has been developed to help users become aware of current functional limitations in patients who have suffered a VTE, whether or not as a result of the specific VTE, and to objectively determine the degree of disability,
Time frame: 30 days, 6 and 12 months
Quality of life using PEmb-QOL
PEmb-QOL is a questionnaire that assesses post-pulmonary embolism quality of life in the context of pulmonary-specific symptoms. The PEmb-QOL questionnaire contains six dimensions based on the contents of the items: frequency of complaints, limitations in activities of daily living, work-related problems, social limitations, intensity of complaints and emotional complaints. Higher scores indicate worse outcome.
Time frame: 6 and 12 months
Quality of life using SF-36
The SF-36 questionnaire is a generic quality of life measure containing eight health domains (physical functioning, physical role, pain, general health, vitality, social function, emotional role functioning, and mental health). The scoring is on a 0-100 scale, with a higher score indicating better health. Scores are combined into two overall summary scores: physical health summary score and mental health summary score.
Time frame: 6 and 12 months
Quality of life using EQ-5D scale
The EQ-5D is a patient reported outcome that provides a simple descriptive profile and single index value for health status. The questionnaire consists of 5 questions pertaining to specific health dimensions, including mobility, self-care, usual activities, pain/discomfort, anxiety/depression, and overall health status rating scale.
Time frame: 6 and 12 months
Diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH)
CTEPH will be diagnosed by the investigational site according to presence of all of the following criteria: 1. At least one mismatched segmental perfusion defect demonstrated by ventilation/perfusion scanning after 3 months of adequate therapeutic anticoagulation 2. Resting mean pulmonary arterial pressure (mPAP) ≥25 mmHg measured by invasive right heart catheterization 3. Pulmonary capillary wedge pressure ≤15 mmHg.
Time frame: Within 12 months
Plan to share: No
This study is active, not recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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