Internal Medicine · Year 3 · from Internal Medicine

Case 2: Pulmonary Embolism

Patient Presentation

A 58-year-old man with recently diagnosed prostate cancer (2 weeks post-biopsy) presents with sudden-onset shortness of breath and right-sided pleuritic chest pain that started 6 hours ago. He also reports mild hemoptysis. He has been relatively sedentary since his diagnosis while awaiting treatment planning.

Vital Signs

  • Blood Pressure: 108/72 mmHg
  • Heart Rate: 112 bpm
  • Respiratory Rate: 26/min
  • Oxygen Saturation: 89% on room air
  • Temperature: 37.4°C

Physical Examination

  • General: Anxious, mild respiratory distress
  • Cardiovascular: Tachycardic, prominent P2, RV heave
  • Pulmonary: Decreased breath sounds at right base, no wheezes
  • Extremities: Right calf tenderness with mild swelling

Laboratory and Imaging

  • D-dimer: 4,200 ng/mL
  • Troponin I: 0.18 ng/mL (mildly elevated)
  • BNP: 580 pg/mL
  • ABG (room air): pH 7.48, PaCO2 28 mmHg, PaO2 62 mmHg
  • ECG: Sinus tachycardia, S1Q3T3 pattern, right heart strain
  • CT pulmonary angiography: Large saddle pulmonary embolus with bilateral segmental involvement

Clinical Image

Figure 2: CT pulmonary angiography demonstrating a saddle pulmonary embolus at the bifurcation of the main pulmonary artery with extension into both right and left pulmonary arteries.

Image Source: Educational illustration for teaching purposes.

Questions

  1. What is this patient's Pulmonary Embolism Severity Index (PESI) class and risk stratification?
  • A) Low risk - outpatient treatment possible
  • B) Intermediate risk - consider admission
  • C) High risk (massive PE) - requires hemodynamic support
  • D) Not applicable
  1. What findings indicate right ventricular dysfunction in PE?
  • A) Elevated BNP and troponin, RV dilation on CT, ECG changes (S1Q3T3)
  • B) Elevated D-dimer only
  • C) Hypoxemia only
  • D) Pleuritic chest pain
  1. What is the appropriate treatment approach for this intermediate-high risk PE?
  • A) Thrombolysis
  • B) Anticoagulation with close monitoring; consider thrombolysis if hemodynamic deterioration
  • C) Surgical embolectomy
  • D) Anticoagulation and early discharge
  1. What is the role of thrombolysis in PE?
  1. What are the long-term anticoagulation considerations for cancer-associated thrombosis?

Answers

  1. B) Intermediate risk - consider admission - This patient has:
  • Submassive/intermediate-risk PE: Hemodynamically stable but with RV dysfunction
  • Risk factors: Cancer, elevated troponin and BNP, RV strain on ECG/CT
  • Requires hospital admission for monitoring and anticoagulation
  • Not massive PE (would require shock/hypotension)
  1. A) Elevated BNP and troponin, RV dilation on CT, ECG changes (S1Q3T3) - RV dysfunction markers:
  • Elevated troponin (myocardial injury)
  • Elevated BNP (RV strain)
  • RV/LV ratio >0.9 on CT
  • RV dilation on echocardiography
  • ECG: S1Q3T3, T-wave inversions V1-V4, right bundle branch block
  • These indicate intermediate-high risk requiring close monitoring
  1. B) Anticoagulation with close monitoring; consider thrombolysis if hemodynamic deterioration - Management:
  • Start anticoagulation immediately (LMWH, fondaparinux, or UFH for cancer)
  • ICU or step-down monitoring
  • If hemodynamic deterioration (shock, persistent hypotension), escalate to thrombolysis
  • Catheter-directed therapy is an alternative to systemic thrombolysis
  1. Role of thrombolysis in PE:
  • Massive/high-risk PE (with hemodynamic instability): Thrombolysis indicated if no contraindications
  • Intermediate-risk PE: Consider if clinical deterioration; routine use not recommended
  • Low-risk PE: Not indicated
  • Systemic thrombolysis: Alteplase 100 mg over 2 hours
  • Catheter-directed thrombolysis: Lower dose, may reduce bleeding risk
  • Contraindications: Recent surgery, active bleeding, stroke history, intracranial disease
  1. Anticoagulation for cancer-associated thrombosis:
  • LMWH was traditional standard of care (CLOT trial)
  • DOACs (edoxaban, rivaroxaban) are now preferred for most cancer-associated VTE (non-GI cancers)
  • Avoid DOACs in GI/GU malignancies (increased bleeding risk)
  • Duration: Extended/indefinite while cancer is active or during treatment
  • Reassess periodically for bleeding risk vs. thrombotic risk

All cases for this lecture as Markdown