2. DR.USWA
DR.SIDRA
DR.SABIHA
DR.KHURRAM
ACUTE PULMONARY
EMBOLISM

3. Perspective
 A common disorder and potentially deadly
 Occurs in approximately 1% of all hospitalized patients and
accounts for around 5% of in-hospital deaths.
 It is a common mode of death in patients with
stroke, malignancy and pregnancy.
 Diagnosis is highly elusive.
 Autopsy reports suggest it is commonly “missed” diagnosed

4.  Presentation is often “atypical”.
 Signs and symptoms are frequently vague and
nonspecific.
 Untreated mortality rate of 20% - 30%,
plummets to 5% with timely intervention.

5. Case
 A 48-year-old woman is brought to the emergency room
complaining of a sudden onset of dyspnea. She reports she
was standing in the kitchen making dinner, when she
suddenly felt as if she could not get enough air, her heart
started racing, and she became lightheaded and felt as if
she would faint.
 On examination, she is tachypneic with a respiratory rate of
28 breaths per minute, oxygen saturations 84% on room
air, heart rate 124 bpm, and blood pressure 118/89 mm Hg.
She appears uncomfortable, diaphoretic, and frightened.
Her right leg is moderately swollen from mid-thigh to her
feet, and her thigh and calf are mildly tender to palpation.
Her chest x-ray is interpreted as normal.

6. Epidemiology & Pathophysiology
 Thrombi commonly form in deep veins of calf and propagate
into the proximal veins of the leg from where they embolize.
 80% of pulmonary emboli arise from the propagation of
proximal lower limb DVT
Remaining 20% arise from
 Pregnancy related DVT
 Upper extremity DVT
 Air, fat and amniotic fluid embolism.

7. • THROMBOSIS:TRIGGERED BY
(VIRCHOW’S TRIAD)
• 1.VENOSTASIS
• 2.VESSEL WALL INFLAMMATION
• 3.HYPERCOAGULABILITY
• ALL CLINICAL RISK FACTORS FOR
DVT/PE HAVE THEIR BASIS IN ONE
OR MORE ELEMENTS OF THE TRIAD.
Risk Factors

8. Vessel Injury
 Recent surgery
 Recent major trauma
Venous Stasis
 Prolonged bed rest
 Recent cast or external fixator
 Long-distance travel or long flight

9. Acquired Inherited
 Malignancy
 Pregnancy
 OCPs
 Lupus anticoagulant
 Nephrotic syndrome
 Factor V Leiden
mutation
 Protein C deficiency
 Protein S deficiency
 Antithrombin III
deficiency
Hypercoagulable State

10. Symptoms Signs
 Dyspnea >80%
 Pleuritic chest pain
 Sub-sternal chest pain
 Cough
 Hemoptysis
 Leg pain
 Tachypnea >90%
 Tachycardia
 Loud P2
 3rd or 4th heart sound
 Crackles
 Cyanosis
Clinical Presentation

11. Clinical Probability Scoring

12. Wells’ Score
Clinical symptoms of DVT
(leg swelling, pain with
palpation)
3.0
Other diagnosis less likely
than PE
3.0
Heart rate >100 1.5
Immobilization (≥3 days)
or surgery in the previous
four weeks
1.5
Previous DVT/PE 1.5
Hemoptysis 1.0
Malignancy 1.0
Wells criteria
High >6.0
Moderate 2.0 to 6.0
Low <2.0
Modified Wells criteria
PE likely >4.0
PE unlikely ≤4.0

13. P A T I E N T S W I T H H I G H O R I N T E R M E D I A T E
C L I N I C A L S U S P I C I O N O F P U L M O N A R Y
E M B O L I S M S H O U L D B E P U T O N
A N T I C O A G U L A T I O N
B E F O R E S T A R T I N G I N V E S T I G A T I O N S
Investigations & Diagnosis

14. ECG
 Sinus tachycardia
 S1Q3T3
 RBBB
 RAD
 P Pulmonale
 Simultaneous T wave inversion in
inferior+anteroseptal leads

18. Chest X-ray

20. ECHO
 RV enlargement
 RV free wall hypokinesia with sparing of apex (McConnell sign
94% specificity)
 Septal flattening/ leftward septal shift/Paradoxical septal motion
 Assessment of pulmonary artery pressure
 TR
 Right chamber emboli
 Alternative diagnoses like pericardial effusion, pericardial
temponade, aortic dissection, LVF
 TEE can identify central pulmonary embolism

23. D-Dimer
 Elevated in thrombosis, malignancy, pregnancy, MI,
sepsis, elderly and hospitalized patients
 Useful when low clinical probability for PE
 Levels <500ng/ml rule out PE where clinical
probability is low.
 In high probability patients  proceed to CTPA,
negative d-dimer can miss up to 15% of patients in
this group

24.  ABGs
 Hypoxemia
 Hypocapnia
 Respiratory alkalosis
 Increased A-a gradient
Pulse oximetry
 Decreased oxygen saturation

25. Troponins
Elevated
BNP
Elevated

26. CT Pulmonary Angiography
 First-line diagnostic test
 Quick and non-invasive
 Allows direct visualization of emboli
 Provides alternative diagnoses like aortic dissection,
ACS, consolidation, pneumothorax
 May miss small peripheral emboli

28. V/Q scan
 Seldom used nowadays
 Used when CTPA is contra-indicated
 Gives high, intermediate or low probability for PE
depending upon perfusion defects.
 Normal scan rules out PE.
 May not be useful if pre-existing lung disease.

30. Compression or duplex USG
 For DVTs before proceeding to invasive tests like
pulmonary angiography

31. Pulmonary Angiography
 Gold Standard
 Performed in an Interventional Cath Lab
 Positive result is a “cutoff” of flow or
intraluminal filling defect
 “Court of Last Resort”

34. A Simplified Algorithm

35. Pulmonary
Embolism
Symptoms Right Heart
Strain
Vitals Management
Minor Asymptomatic No Stable Discharged with
LMWH to
Coumadin bridge
Small to
medium
Symptomatic No Stable Admitted in Ward
LMWH to
Coumadin bridge
Sub-massive Symptomatic Yes Stable In ICU
Heparin infusion
to coumadin
bridge
Massive Symptomatic Yes Unstable ICU
O2
Fluids
Thrombolysis
Or embolectomy

36. Heparin
 Available as LMWH or Unfractionated Heparin
 FDA approved dosing:
 LMWH: 1 mg/kg B.D
 Unfractionated: 80 units/kg (or 5000 U) bolus
then 18 units/kg/hr or 1300U/h
 LMWH is preferred in pregnant patients

37. Fondaparinux
 A synthetic pentasaccharide
 Alternative to LMWH
DOSING:
5 mg OD (for body weight below 50 kg)
7.5 mg OD (for body weight b/w 50–100 kg)
10 mg OD (for body weight above 100 kg)

38. Warfarin (Coumadin)
 Vit. K antagonist
 Inhibits hepatic synthesis of factor II, VII, IX, X,
protein C & S.
 Patient is anticoagulated with heparin before
initiating warfarin therapy because it causes
temporary hypercoagulable state in first 5 days of
treatment.
 Target INR is 2. 0– 3.0
 Warfarin alternatives are rivaroxaban, apixaban,
dabigatran & endoxaban.

39. Thrombolysis

40. Thrombolytic Therapy
 Documented massive PE with
 Persistent hypotension
 Syncope with persistent hemodynamic compromise
 Significant hypoxemia
 Cardiogenic shock

41. Alteplase
 100 mg IV over 2 hour
 IV anticoagulation is started immediately after
alteplase.
Streptokinase
 Loading dose 250,000 IU then 100,000 IU per hour
for 24 hour.
 Maximum three million units per 24 hour.

42. Complications of Thrombolytic Therapy
1. ICH
2. Retroperitoneal & GI bleeding
3. Bleeding from surgical wounds

43. Contraindications
 Absolute
1. Active internal bleeding
2. Stroke in last 2 months
 Relative
1. Surgery or trauma in last 6 weeks
2. Uncontrolled hypertension

44. Other Treatment Options
 Embolectomy
 Before thrombolytic therapy this was only therapy
for massive PE
 Now it is performed when thrombolysis is
contraindicated
 Carries a 40% operative mortality
 IVC Filter
 Anticoagulation is contraindicated
 Recurrent VTE despite anticoagulation

45. Secondary prophylaxis

46. • LMWH SC + oral anticoagulation (6 months )
• LMWH (pregnancy)
• Recurrance / unknown origin / permanantly
increased risk like anti phospholipid syndrome
(throughout life)

47. Rivaroxaban
Factor Xa inhibitor
 15mg BD for Ist 3 weeks
 then 20mg OD for next 6 months
 No need of monitoring

48. LMWH
 1mg/kg OD

49. • INDICATIONS
• Contraindications to
anticoagulation
• Failed anticoagulation
• Developed a complication due to
anticoagulation
• Severe cardiopulmonary
compromise where the next PE will
be lethal
IVC Filter

50. C O N S I D E R E D W H E N P A T I E N T ' S
P R E S E N T A T I O N I S S E V E R E E N O U G H T O
W A R R A N T T H R O M B O L Y S I S ( E . G . ,
P E R S I S T E N T H Y P O T E N S I O N ) , B U T
T H R O M B O L Y S I S E I T H E R F A I L S O R I S
C O N T R A I N D I C A T E D .
Embolectomy

51. Catheter embolectomy
 Rheolytic: injecting
pressurized saline through
the catheter's distal tip, which
macerates the emboli
 Rotational: rotational
catheter fragmentation

52. Surgerical Embolectomy
 Performed on cardiopulmonary bypass with clots
extracted from the opened PAs under direct visualization
 Indicated only when
1.Systemic hypotension due to PE in a patient in whom
thrombolysis is contraindicated
 Possible: echocardiographic evidence of an embolus trapped within a
patent foramen ovale, the right atrium, or the right ventricle
2.Limited to large medical centers because an experienced
surgeon and cardiopulmonary bypass are required

53. • S U D D E N C A R D I A C D E A T H
• O B S T R U C T I V E S H O C K
• A R R Y T H M I A S
• H Y P O X I A
• L U N G I N F A R C T I O N
Complications

54. Massive PE
 occlusion of the pulmonary artery that exceeds 50%
of its cross-sectional area, resulting in progressive
hemodynamic compromise
 Usually presenting with systolic blood pressure < 90
mmHg.
 obstruction of the PA to this degree initiates a
cascade of physiologic events, which if not
interrupted early, ultimately results in cardiac arrest
and death in up to 70% of patients in the first hour

55. Medical treatment of Massive PE
 Supplemental oxygen
 High dose IV heparin
 Hemodynamic support
 IV fluids (empiric 500 mL)
 increased right ventricular (RV) wall stress can decrease the ratio
of RV oxygen supply to demand. (ischemia, deterioration of RV
function, and worse RV failure)
 Vasopressors (no evidence for which one)
 Norepinephrine, epinephrine, or dopamine usually first line
 Thrombolytics (if no contraindications)

56. • IMMEDIATE MORTALITY IS HIGH IN
THOSE WITH RIGHT VENTRICULAR
DYSFUNCTION OR CARDIOGENIC
SHOCK.
• ONCE ANTICOAGULATION IS STARTED,
THE RISK OF MORTALITY FALLS
RAPIDLY.
• THE RISK OF RECURRENCE IS HIGHEST
IN THE FIRST 6–12 MONTHS AFTER
THE INITIAL EVENT.
Prognosis

57. • INITIAL RESUSCITATION IS KEY .
• EMPIRIC ANTICOAGULATION SHOULD BE
CONSIDERED WHEN THE DIAGNOSIS
CANNOT BE A MADE IN A TIMELY MANNER.
• ANTICOAGULATION SHOULD BE
PROMPTED WITH APPROPRIATE AGENT(S).
• IVF FILTER SHOULD BE CONSIDERED
WHEN ANTICOAGULATION IS NOT AN
OPTION.
Summary