Symptom-driven Referral for Evaluation of Chronic Thromboembolic Disease or Pulmonary Hypertension in Patients With Previous Acute Pulmonary Embolism

Study Overview
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Brief Summary
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Aim: To investigate if a symptom driven referral for chronic thrombosis in the lungs after acute pulmonary embolism is better than the current approach. Background: A number of patients with chronic thrombosis in the lungs after acute pulmonary embolism have dyspnea and reduced functional capacity without elevated pulmonary arterial pressure at rest (CTED). However, current guidelines for follow-up after acute pulmonary embolism will miss all patients with CTED, as referral for further examination is based on elevated pulmonary arterial pressure on echocardiography. Thus, the prevalence of CTED is unknown. The hypothesis is, that a symptom-driven referral of patients with previous acute pulmonary embolism is more sensitive in diagnosing CTED than the current approach. Methods and materials: Patients diagnosed with acute pulmonary embolism in Region Midt (approx. 350 per year) will be screened for non-recovery or persistent pulmonary embolism related symptoms during their 3-6 months follow up at their local outpatient clinic. If the patient has persistent symptoms they will be referred to a scintigraphy. If CTED is suspected from the scintigraphy, the patient will be referred for full CTED work-up. The investigators expect to screen 300 patients for persistent symptoms with an expected study time of 3 years.

Official Title
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Symptom-driven Referral for Evaluation of Chronic Thromboembolic Disease or Pulmonary Hypertension in Patients With Previous Acute Pulmonary Embolism

Conditions
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Chronic Thromboembolic Pulmonary Disease

Intervention / Treatment
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* Diagnostic Test: CTEPH/CTED work-up


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute PE diagnosed by CT or V/Q-scan within the last year. Non-recovery or persistent PE related symptoms assessed by a MRC breathlessness score or WHO functional class. Age >= 18 and < 80 Exclusion Criteria: Contraindications or unable to perform 6 minutes walk distance (6MWD) and/or cardiopulmonary exercise test. Contraindications to CT pulmonary angiography. Congestive heart failure (LVEF <40%). COPD or restrictive lung disease, severe or worse (FEV1 <50% and >=1 exacerbation causing hospital admission per year (GOLD grade 3 and 4 class C and D)). Lactating or pregnant. Unable or unwilling to provide written informed consent. Paroxysmal or persistent atrial fibrillation. Other known cause of PE related symptoms.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 79 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: CTEPH/CTED work-up<br> | Diagnostic Test: CTEPH/CTED work-up<br>* Patients diagnosed with acute pulmonary embolism (PE) in Region Midt (approx. 350 per year) will be screened for non-recovery or persistent PE related symptoms during their 3-6 months follow up at their local outpatient clinic. If the patient has persistent symptoms they will be referred to a V/Q-scan. If a V/Q mismatch is present, the patient will be referred to a full work-up for CTEPH/CTED.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of CTED |  | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic accuracy of dual energy CT perfusion and pulmonary angiography. | Sensibility, specificity, positive predictive value and negative predictive value | 3 years |