What is the recommended assessment and treatment approach for an older adult patient with a history of cardiovascular disease suspected of having pulmonary embolism (PE), using the modified Wells' score or Geneva score for evaluation?

Modified PE Scoring in Older Adults with Cardiovascular Disease

Use Wells Score Over Geneva Score for Risk Stratification

In older adults with cardiovascular disease and suspected PE, use the Wells score as your primary clinical prediction rule, as it demonstrates superior diagnostic accuracy compared to the Geneva score in elderly hospitalized patients (area under ROC curve 0.91 vs 0.69, P<0.001), with better positive and negative likelihood ratios (LR+ 7.90-13.5 vs 1.34-1.46; LR- 0.23-0.47 vs 0.54-0.66). 1

Clinical Assessment Algorithm

Step 1: Calculate Wells Score

Calculate the Wells score using these variables 2, 3:

• Clinical signs/symptoms of DVT (leg swelling, pain on palpation): 3 points
• PE as likely as or more likely than alternative diagnosis: 3 points
• Heart rate >100 bpm: 1.5 points
• Immobilization ≥3 days or surgery within 4 weeks: 1.5 points
• Previous DVT/PE: 1.5 points
• Hemoptysis: 1 point
• Active malignancy: 1 point

Step 2: Risk Stratification

Categorize patients based on total score 2, 3:

• Low probability: 0-1 points (3.6% PE prevalence)
• Moderate probability: 2-6 points (20.5% PE prevalence)
• High probability: >6 points (66.7% PE prevalence)

Alternatively, use dichotomous interpretation 2:

• PE unlikely: ≤4 points (7.8% PE prevalence)
• PE likely: >4 points (40.7% PE prevalence)

Diagnostic Testing Strategy

For Low-to-Moderate Probability (Wells ≤6)

Obtain age-adjusted D-dimer testing 4, 5:

• Use age-adjusted cutoff: age × 10 ng/mL for patients >50 years (not the standard 500 ng/mL)
• This increases PE exclusion from 6.4% to 30% without additional false negatives 4
• If D-dimer negative: PE excluded, no imaging needed 4, 5
• If D-dimer positive: Proceed to CT pulmonary angiography (CTPA) 4, 3

For High Probability (Wells >6)

Proceed directly to CTPA without D-dimer testing, as negative D-dimer will not obviate imaging need 4, 3

Special Considerations for Elderly with Cardiovascular Disease

Critical Risk Factors in This Population

Monitor for factors significantly associated with 30-day mortality 6:

• Active malignancy (P<0.05)
• Altered mental status (P<0.05)

Pitfalls to Avoid

• Do not rely on Geneva score in elderly hospitalized patients - it shows significantly inferior diagnostic accuracy (AUC 0.69 vs 0.91 for Wells) 1
• PE is easily missed in elderly with pre-existing cardiorespiratory disease - maintain low threshold for suspicion 3
• D-dimer has limited utility in hospitalized patients - frequently elevated due to comorbidities, recent surgery, infection, and inflammation; <10% of hospitalized patients have negative D-dimer 4
• Do not use PERC criteria in this patient - cardiovascular disease and older age typically violate PERC prerequisites 2, 4

Imaging Interpretation

CTPA Results

• Sensitivity >95% for segmental or larger emboli 4
• If positive: Initiate therapeutic anticoagulation immediately 3
• If negative in high-probability patients: Consider additional testing (lower extremity venous ultrasound) before definitively ruling out PE, as false-negative rate ranges 5.3-40% 4

Alternative Imaging

Reserve ventilation-perfusion (V/Q) scanning for contraindications to CTPA, with sensitivity 85% and specificity 93% 4

Prognostic Assessment

After diagnosis, calculate PESI score for 30-day mortality prediction - it is the strongest categorical predictor in elderly PE patients (P<0.05) 6