Subsegmental (Single or Multiple) Pulmonary EmbolismSSPENCT01455818
A Study to Evaluate the Safety of Withholding Anticoagulation in Patients With Subsegmental PE Who Have a Negative Serial Bilateral Lower Extremity Ultrasound
An observational study of Subsegmental (Single or Multiple) Pulmonary Embolism, run by Ottawa Hospital Research Institute at 9 sites in 3 countries.
Trial summary
Blood clots in lung arteries (pulmonary embolism) are usually detected using a radiological test called computed tomography (CT scan). As technology advances, the CT scans are able to detect smaller and smaller blood clots. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Subsegmental (Single or Multiple) Pulmonary Embolism
- How many people
- 292 participants
- Where
- 9 sitesin 3 countries
- Study dates
- Mar 2011to May 2021
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Consecutive patients with symptomatic, isolated SSPE* (any number), that are newly diagnosed by computed tomographic pulmonary angiography will be eligible to participate in the study.
Who may be able to join
- Age greater or equal to 18 years old.
- Patients with newly diagnosed isolated SSPE* (any number).
- Isolated SSPE is defined as CTPA demonstrating an intraluminal filling defect in a subsegmental artery with no filling defects visualized at more proximal pulmonary artery levels.
Who cannot join
- Proximal lower extremity (popliteal vein or above) or upper extremity (subclavian vein or above) DVT.
- Need for long term oral anticoagulant therapy for reasons other than VTE.
- SSPE diagnosed in a hospitalized patient (> 48 hours after hospital admission).
- Requiring oxygen therapy to maintain an O2 saturation over 92%
- Previous history of DVT (proximal or distal) of upper or lower extremities, PE, or unusual site thrombosis (e.g. splanchnic or cerebral vein thrombosis).
- Geographically inaccessible for follow-up
Show all 12Show fewer
- Active Malignancy (defined as other than basal-cell or squamous cell carcinoma of the skin; cancer within the past 6 months; any treatment for cancer in the past 6 months; or recurrent or metastatic cancer)
- Pregnancy
- Have received more than 48 hours of therapeutic anticoagulation.
- Prophylactic dose allowed if required for separate indication and acceptable by the investigator.
- Unable/refuse to sign informed consent
- Asymptomatic SSPE (e.g. SSPE is an incidental finding on a CT scan conducted for reasons other than suspected PE)
Trial locations and contacts
9 sites in 3 countries.
9 sites in 3 countries
Canada7 sites
Capital District Health Authority
Halifax, Nova Scotia, B3H 1V7
Hamilton General Hospital
Hamilton, Ontario, L8L 2X2
London Health Sciences Centre
London, Ontario
Sir Mortimer B. Davis Jewish General Hospital
Montreal, Quebec, H3T 1E2
St. Mary's Hospital Centre
Montreal, Quebec, H3T 1MS
Ottawa Hospital
Ottawa, Ontario, K1H 8L6
Toronto General Hospital
Toronto, Ontario, M5G 2C4
About this study
Official title: A Multicenter Prospective Cohort Management Study to Evaluate the Safety of Withholding Anticoagulation in Patients With Subsegmental PE Who Have a Negative Serial Bilateral Lower Extremity Ultrasound
Blood clots in lung arteries (pulmonary embolism) are usually detected using a radiological test called computed tomography (CT scan). As technology advances, the CT scans are able to detect smaller and smaller blood clots. Over time, the frequency of blood clots in the pulmonary arteries has increased significantly (CT scan are now detecting very small blood clots that the investigators could not see before). As a result, more and more people are on blood thinners to treat these small blood clots but their true clinical significance is unknown.
The management of blood thinners is costly and also utilizes scarce healthcare resources. These blood thinners need to be monitored with frequent blood work. Furthermore, every year, approximately 3 percent of patients on blood thinners will have a major bleeding event requiring medical attention.
Read more
The investigators don't think that treating these small blood clots in the pulmonary arteries detected on CT scan is worth the risk of bleeding from the blood thinners.
The main goal of this study is to find out if it is safe to not treat very small blood clots in the pulmonary arteries.
The investigators plan to follow 300 patients with small blood clots in their lungs for 90 days. These patients will not be treated with blood thinners but will be followed closely with other non-invasive tests to avoid progression or recurrence of blood clots.
- Medical subject headings
- Pulmonary Embolism
What is being measured
The primary outcome is the main question the study is designed to answer.
Recurrent VTE
Recurrent VTE will be diagnosed according to previously published criteria: 1)Lower extremity US revealing non-compressibility at the trifurcation of the popliteal vein or above; OR 2) Venography demonstrating a constant intraluminal filling defect above the trifurcation of the popliteal vein; OR 3) Pulmonary angiography demonstrating a new constant intraluminal filling defect or a cut off of a vessel; OR 4) Ventilation/perfusion scanning with a high probability of PE; OR 5) CTPA demonstrating new intraluminal filling defect in a subsegmental or greater sized pulmonary artery; OR 6) PE discovered at autopsy.
Measured: 90 day follow-up
Secondary outcomes (5)
Interobserver agreement for SSPE diagnosis on CTPA (local Vs. central interpretation)
Measured: 90 day follow-up
Death due to PE
Definition of death due to PE Certain: hypotension, hypoxia, cardiac arrest with no other explanation other than PE and autopsy or radiographic confirmation Highly probable: criteria for certain but another disease could have caused the death Probable: other cause suspected based on clinical evidence but 100% certainty not available Unlikely: all other cases
Measured: 90 day follow-up
Death probably due to PE
Certain: hypotension, hypoxia, cardiac arrest with no other explanation other than PE and autopsy or radiographic confirmation Highly probable: criteria for certain but another disease could have caused the death Probable: other cause suspected based on clinical evidence but 100% certainty not available Unlikely: all other cases
Measured: 90 day follow-up
Major bleeding
Major bleeding will be defined according to previously published criteria (51):
- Fatal bleeding; OR
- Symptomatic bleeding in a critical area or organ, such as intracranial, intraspinal, intraocular, retroperitoneal, intraarticular or pericardial, or intramuscular with compartment syndrome; OR
- Bleeding causing a fall in hemoglobin level of 20 g/L (1.24 mmol/L) or more, or leading to transfusion of two or more units of whole blood or red cells
Measured: 90 day follow-up
Minor bleeding
Minor bleeding will be defined as any bleeding not meeting the requirements of a major bleeding event.
Measured: 90 day follow-up
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Oct 2011 (estimated)
- Study startMar 2011
- Primary completionMar 2021
- Study completionMay 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Subsegmental (Single or Multiple) Pulmonary EmbolismStudies of the same condition, open and under way.
- More trials run by Ottawa Hospital Research InstituteThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 292 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ottawa Hospital Research Institute
- Sponsor type
- University, hospital or other
- Collaborators
- University Hospital, Brest
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01455818
- Sponsor's protocol ID
- 2009600-01H
- Acronym
- SSPE
- Status last verified
- May 2021
- First submitted
- 18 Oct 2011
- Last updated
- 28 May 2021
- Results posted
- No
- Data monitoring committee
- Yes
Publications
Le Gal G, Kovacs MJ, Bertoletti L, Couturaud F, Dennie C, Hirsch AM, Huisman MV, Klok FA, Kraaijpoel N, Mallick R, Pecarskie A, Pena E, Phillips P, Pichon I, Ramsay T, Righini M, Rodger MA, Roy PM, Sanchez O, Schmidt J, Schulman S, Shivakumar S, Trinh-Duc A, Verdet R, Vinsonneau U, Wells P, Wu C, Yeo E, Carrier M; SSPE Investigators. Risk for Recurrent Venous Thromboembolism in Patients With Subsegmental Pulmonary Embolism Managed Without Anticoagulation : A Multicenter Prospective Cohort Study. Ann Intern Med. 2022 Jan;175(1):29-35. doi: 10.7326/M21-2981. Epub 2021 Nov 23.
PubMed 34807722
Study at a glance
From the registry record, last updated by the sponsor on 28 May 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Multicenter Prospective Cohort Management Study to Evaluate the Safety of Withholding Anticoagulation in Patients With Subsegmental PE Who Have a Negative Serial Bilateral Lower Extremity Ultrasound
- ClinicalTrials.gov ID
- NCT01455818
- Acronym / sponsor ID
- SSPE / 2009600-01H
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 292 participants (actual)
- Lead sponsor
- Ottawa Hospital Research InstituteUniversity, hospital or other
- Collaborators
- University Hospital, Brest
- Study start
- Mar 2011
- Primary completion
- Mar 2021 (actual)
- Study completion
- May 2021 (actual)
- First posted
- 20 Oct 2011 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Blood clots in lung arteries (pulmonary embolism) are usually detected using a radiological test called computed tomography (CT scan). As technology advances, the CT scans are able to detect smaller and smaller blood clots. Over time, the frequency of blood clots in the pulmonary arteries has increased significantly (CT scan are now detecting very small blood clots that the investigators could not see before). As a result, more and more people are on blood thinners to treat these small blood clots but their true clinical significance is unknown.
The management of blood thinners is costly and also utilizes scarce healthcare resources. These blood thinners need to be monitored with frequent blood work. Furthermore, every year, approximately 3 percent of patients on blood thinners will have a major bleeding event requiring medical attention.
The investigators don't think that treating these small blood clots in the pulmonary arteries detected on CT scan is worth the risk of bleeding from the blood thinners.
The main goal of this study is to find out if it is safe to not treat very small blood clots in the pulmonary arteries.
The investigators plan to follow 300 patients with small blood clots in their lungs for 90 days. These patients will not be treated with blood thinners but will be followed closely with other non-invasive tests to avoid progression or recurrence of blood clots.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Consecutive patients with symptomatic, isolated SSPE* (any number), that are newly diagnosed by computed tomographic pulmonary angiography will be eligible to participate in the study.
Key inclusion criteria (3 listed)
- Age greater or equal to 18 years old.
- Patients with newly diagnosed isolated SSPE* (any number).
Key exclusion criteria (12 listed)
- Proximal lower extremity (popliteal vein or above) or upper extremity (subclavian vein or above) DVT.
- Need for long term oral anticoagulant therapy for reasons other than VTE.
- SSPE diagnosed in a hospitalized patient (> 48 hours after hospital admission).
- Requiring oxygen therapy to maintain an O2 saturation over 92%
- Previous history of DVT (proximal or distal) of upper or lower extremities, PE, or unusual site thrombosis (e.g. splanchnic or cerebral vein thrombosis).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Recurrent VTE
Time frame: 90 day follow-up
Recurrent VTE will be diagnosed according to previously published criteria: 1)Lower extremity US revealing non-compressibility at the trifurcation of the popliteal vein or above; OR 2) Venography demonstrating a constant intraluminal filling defect above the trifurcation of the popliteal vein; OR 3) Pulmonary angiography demonstrating a new constant intraluminal filling defect or a cut off of a vessel; OR 4) Ventilation/perfusion scanning with a high probability of PE; OR 5) CTPA demonstrating new intraluminal filling defect in a subsegmental or greater sized pulmonary artery; OR 6) PE discovered at autopsy.
5 secondary outcomes
Interobserver agreement for SSPE diagnosis on CTPA (local Vs. central interpretation)
Time frame: 90 day follow-up
Death due to PE
Time frame: 90 day follow-up
Death probably due to PE
Time frame: 90 day follow-up
Major bleeding
Time frame: 90 day follow-up
Minor bleeding
Time frame: 90 day follow-up
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 May 2021.
- Derived from this study: PubMed 34807722Le Gal G, Kovacs MJ, Bertoletti L, Couturaud F, Dennie C, Hirsch AM, Huisman MV, Klok FA, Kraaijpoel N, Mallick R, Pecarskie A, Pena E, Phillips P, Pichon I, Ramsay T, Righini M, Rodger MA, Roy PM, Sanchez O, Schmidt J, Schulman S, Shivakumar S, Trinh-Duc A, Verdet R, Vinsonneau U, Wells P, Wu C, Yeo E, Carrier M; SSPE Investigators. Risk for Recurrent Venous Thromboembolism in Patients With Subsegmental Pulmonary Embolism Managed Without Anticoagulation : A Multicenter Prospective Cohort Study. Ann Intern Med. 2022 Jan;175(1):29-35. doi: 10.7326/M21-2981. Epub 2021 Nov 23.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
9 sites in 3 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Subsegmental (Single or Multiple) Pulmonary Embolism, run by Ottawa Hospital Research Institute at 9 sites in 3 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 28 May 2021. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 9 sites in Canada, France, Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Recurrent VTE (time frame: 90 day follow-up). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01455818, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 May 2021.