Pulmonary Embolism

Diagnosis and Management

Sherstin T Lommatzsch, MDAssistant Professor of MedicineNational Jewish HealthDenver, CO

Objectives

• Definitions

• Diagnosis

• Treatment

Definitions

– Obstruction of a pulmonary artery:

• Air

• Fat

• Tumor

• Thrombus

Definitions

• Acute vs Chronic

– Acute:

• Symptoms develop within 1 to 2 hours following obstruction

– Chronic:

• Symptoms develop over years due to pulmonary hypertension

Definitions

• Massive vs Submassive

• Massive

– Systolic blood pressure < 90mmHg or decrease of > 40mmHg from baseline lasting at least 15 min

– Likely if signs of elevated central venous pressure

– Risk for death 24-72 hrs

• Submassive

– All othersJames Heilman, MD

Definitions

• Saddle Pulmonary Embolism

– Caught at bifurcation of the right and left pulmonary arteries

Definitions

Acute Thromboembolic Pulmonary Embolism

DiagnosisHigh Clinical Suspicion!!!

Symptoms

• Dyspnea (73%)

• Pleuritic pain (44%)

• Calf/Thigh pain (44%)

• Calf/Thigh swelling (41%)

• Cough (34%)

• Orthopnea (28%)

• Wheezing (21%)

Signs

• Tachypnea (54%)

• Tachycardia (23%)

• Rales (18%)

• Diminished breath sounds (17%)

• Loud P2 (15%)

• Jugular Venous Distention (14%)

DiagnosisHigh Clinical Suspicion!!!

• Clinical Suspicion Alone:

– Sensitivity = 85%

– Specificity = 51%

Diagnosis

EKGUncommon – more frequently associated with massive PE and Cor Pulmonale

Diagnosis

Laboratory Studies• D-Dimer

– ELISA or Quantitative Rapid• Sensitivity = 90%

• ABG– Misleading:

• 18% have normal PaO2• 6% have normal a-A gradient

• BNP– Sensitivity 60%– Specificity 62%– More prognostic value

• Troponin I or T– Elevated in 30-50%– More prognostic Value

Radiographic Studies

• CXR– Findings also seen in other

pathology

• Pulmonary Angiography– Gold Standard

• Spiral CT– Sensitivity = 83%

– Specificity = 96%

• V/Q Scan– Excludes PE if Normal

• LE Venous Doppler

Diagnosis

Wells Criteria Clinical Suspicion

PLUS

Radiographic Information

Date of download: 10/28/2013Copyright © 2012 American Medical

Association. All rights reserved.

From: Effectiveness of Managing Suspected Pulmonary Embolism Using an Algorithm Combining Clinical Probability, D-Dimer Testing, and Computed Tomography

JAMA. 2006;295(2):172-179. doi:10.1001/jama.295.2.172

Figure Legend:

Modified Wells Criteria

Date of download: 11/3/2013Copyright © 2012 American Medical

Association. All rights reserved.

From: Effectiveness of Managing Suspected Pulmonary Embolism Using an Algorithm Combining Clinical Probability, D-Dimer Testing, and Computed Tomography

JAMA. 2006;295(2):172-179. doi:10.1001/jama.295.2.172

*Excludes 29 patients treated with anticoagulant therapy for reasons other than venous thromboembolism.†Excludes 69 patients treated with anticoagulant therapy for reasons other than venous thromboembolism.

Figure Legend:

Wells Criteria

Treatment(Standard)

GOAL

Achieve full anticoagulation within 24H

Treatment(Standard)

Immediate

• Low Molecular Weight Heparins (SC)– enoxaperin, nadroparin,

tinzaparin, daltiparin

• Factor Xa Inhibitor (SC)– fondaparinux

• Unfractionated Heparin (IV or SC)

Long-Term

• Vitamin K Inhibitors– Warfarin

• Factor Xa Inhibitor– Rivaroxaban

Treatment(Standard)

Immediate

• Low Molecular Weight Heparins (SC)– enoxaperin

• Factor Xa Inhibitor (SC)– fondaparinux

• Unfractionated Heparin (IV or SC)

First Choice• Less Major Bleeding Complications• Fewer Recurrent Thromboembolic Events• Lower Mortality

Second Choice• Persistent Hypotension• Creatinine Clearance < 30mL/min• Increased Bleeding Risk• Possible Thrombolysis• SC Route Absorption Concerns

•Body Habitus

Treatment(Standard)

Immediate

• Low Molecular Weight Heparins (SC)– enoxaperin, nadroparin,

tinzaparin, daltiparin

• Factor Xa Inhibitor (SC)– fondaparinux

• Unfractionated Heparin (IV or SC) – weight based protocol

First Choice

• Less Major Bleeding Complications• Fewer Recurrent Thromboembolic Events• Lower Mortality• Ensures rapid and adequate therapy • Less Thrombocytopenia• Dosing Convenience

Second Choice

• Persistent Hypotension• Creatinine Clearance < 30mL/min• Increased Bleeding Risk• Possible Thrombolysis• SC Route Absorption Concerns

•Body Habitus

Treatment(Standard)

Long-Term

• Vitamin K Inhibitors– Warfarin

• Factor Xa Inhibitor– Rivaroxaban

• Oral Variable Dosing -> INR• Goal INR 2-3• Reversible

• Oral Fixed Dosing• Renal Adjustment Required• Not Recommended in Hepatic Dz• NON-Reversible

Treatment(Standard)

Long-Term

• Vitamin K Inhibitors– Warfarin

• Factor Xa Inhibitor– Rivaroxaban

• Oral Variable Dosing -> INR• Goal INR 2-3• Reversible

• May begin during 1st 24H of full

heparin, etc therapy • 5 Day overlap with heparin/etc AND• 24H of INR = 2-3• Do NOT begin prior to heparin/etc

• Oral Fixed Dosing• Renal Adjustment Required• Not Recommended in Hepatic Dz• NON-Reversible

Treatment(Standard)

Complications

• Significant Bleeding

– Risk Factors

– Bleeding Risk (%)

• Older Age (> 65)• Thrombocytopenia• Fall Risk• Hepatic Disease• Compliance Concerns• Concominent Anti-Platelet Therapy

• Recent Surgery• Cancer• Renal Disease• Alcohol Use• Diabetes Mellitus• Prior Significant Bleeding

First 3 Months Per Year Following • No Risk Factors 1.6 0.8• 1 Risk Factor 3.2 1.6• 2 Risk Factors 12.8 > 6.5

Treatment(Standard)

Duration

• Based on risk of recurrence following 1st PE

– Provoked versus UnprovokedTraumaImmobilizationSurgeryDrugsPregnancy

3 Months 3 Months? Longer

• Without Anticoagulation•5 yr 25% Risk Recurrence

• With Anticoagulation• 1st yr: 8.8% reduction risk• 5 yrs: 26.4% reduction risk

Treatment(Emerging)

• Systemic Thrombolysis– Considered in patients with confirmed pulmonary

embolism AND hypotension

– No difference in mortality or recurrent thromboembolic events when compared to anticoagulation alone.

– Some improvement in various outcomes:• Acute Improvement Right Ventricular Function

• Lower Long-term Pulmonary Artery Pressures

• Trend toward better mortality in hypotensive patients

Treatment(Emerging)

• Systemic Thrombolysis

– Agents

• Recombinant tissue plasminogen activator (tPA)– Most commonly used

• Streptokinase

• Recombinant human urokinase

– Infusion Method

• bolus

Check aPTT after lytic given and start heparin without bolus when < twice normal

Treatment(Emerging)

• Systemic Thrombolysis

– Massive PE without hypotension

• Dilated Right Ventrical

• Right Ventricular Dysfunction

• Elevated BNP

• Elevated Troponin

• Severe Hypoxemia

• Persistent Tachycardia

• Right Ventricular EKG Changes

Physician Judgement

Treatment(Emerging)

• Systemic Thrombolysis– Risk

• Bleeding Intracranial Hemorrhage

– Contraindications (similar to thrombolysis in CVA)

• Intracranial neoplasm

• Intracranial surgery within 2 months

• GI Bleeding or other significant internal bleeding within prior 6 months

• Uncontrolled HTN: SBP>200mmHg and/or DBP>110mmHg

• Trauma within preceding 2 months

• Ischemic CVA > 6 months prior to PE

• Bleeding coagulopathies

• Surgery within prior 10 Days

• Thrombocytopenia < 100, 000 platelets/mm3

Treatment(Emerging/Alternative)

• Catheter Directed Thrombolysis

• Embolectomy

– Surgical versus Catheter

Clot in ASD or PFO

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