Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Anticoagulate immediately unless absolute contraindication.
- If massive PE → systemic lysis unless contraindicated; if contraindicated, consider CDT or surgical embolectomy.
- If submassive → monitor closely; consider CDT if deteriorating or high-risk features.
- Plan duration of anticoagulation based on provoked vs unprovoked and bleeding risk; evaluate for cancer and thrombophilia selectively.
Clinical Synopsis & Reasoning
Classify PE as massive (hypotension/shock), submassive (RV dysfunction/biomarkers, normotensive), or low risk. Start anticoagulation promptly. Consider systemic thrombolysis for massive PE; catheter-directed thrombolysis/thrombectomy for selected submassive with clinical deterioration; assess bleeding risk.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| CTA pulmonary angiography | Diagnosis | Central/lobar thrombus; RV/LV ratio | Gold standard in stable |
| Echo and biomarkers (troponin/BNP) | Risk | RV strain, prognostic info | Useful in unstable/contrast contraindication |
| PESI/sPESI score | Disposition | Risk stratification | Outpatient possible if very low risk |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Hypotension (massive PE) or rising troponin/BNP with RV strain | Shock/decompensation risk | Thrombolysis or catheter-directed therapy; ICU |
| Active bleeding/recent surgery | Lysis contraindication | Favour anticoagulation alone or thrombectomy |
| Cancer or unprovoked PE | Recurrence risk | Plan extended anticoagulation; oncology workup |
| Pregnancy/post-partum | Special populations | Heparin preferred; multidisciplinary care |
| Worsening hypoxemia despite O2 | Decompensation | Escalate support; consider VA-ECMO in select centers |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Unfractionated heparin infusion (or LMWH) | Anticoagulant | Immediate | Preferred if procedures anticipated | Bridge to DOAC |
| Alteplase 100 mg IV over 2 h (massive PE) | Thrombolytic | Hours | For shock/hypotension | Bleeding/ICH risk |
| Catheter-directed therapy (low-dose lysis or thrombectomy) | Interventional | Hours | For selected submassive with deterioration | Institution dependent |
| DOACs for maintenance (apixaban/rivaroxaban) | Anticoagulant | Hours | 3–6 months or extended | Contraindications apply |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- ESC/ACCP guidelines on PE diagnosis and management — Link