Chronic Thromboembolic Pulmonary Hypertension (CTEPH) Prediction Score Calculator

Known hypothyroidism -- select -- Yes No Symptom onset > 2 weeks before index PE diagnosis -- select -- Yes No Right ventricular dysfunction on CT or echocardiography (at index PE) -- select -- Yes No Known diabetes mellitus -- select -- Yes No Thrombolytic therapy or embolectomy for the acute PE event -- select -- Yes No CTEPH Prediction Score: Explanation and Clinical Context Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension caused by non-resolving, organized thromboemboli and associated microvasculopathy that persist after acute pulmonary embolism (PE). Early recognition matters because timely referral to a CTEPH center enables curative pulmonary endarterectomy or balloon pulmonary angioplasty and optimized medical therapy. The CTEPH prediction score by Klok and colleagues was derived from 772 PE patients and assigns weighted points to six readily available variables at the time of index PE: unprovoked PE (+6), known hypothyroidism (+3), symptom onset >2 weeks before PE diagnosis (+3), right ventricular dysfunction on CT or echocardiography (+2), known diabetes mellitus (−3), and thrombolytic therapy or embolectomy for the acute PE event (−3).

A total score of >6 indicates high risk, while ≤6 indicates low risk. In the derivation cohorts, the tool separated patients into a low-risk group with ~0.4% CTEPH incidence and a higher-risk group with ~10% incidence on follow-up. Subsequent implementation studies (e.g., InShape II) integrated this score into structured post-PE follow-up to safely rule out CTEPH earlier and reduce unnecessary echocardiograms; nevertheless, external validations show mixed discriminative performance across settings, so clinicians should apply it alongside symptoms, imaging, and local pathways.

Practically, use this calculator at the post-PE follow-up (≈3 months) to frame pre-test probability and decide on ventilation–perfusion scanning and referral, especially if exertional dyspnea persists or CT at index PE already suggested chronic thromboembolic disease.