Acute Management of
Pulmonary Embolism
Dr Alex West
Respiratory Consultant
Guy’s and St Thomas’ Hospital
London
Declarations - none
Order of Play
• Up date in Diagnostic Imaging
- CTPA and V:Q SPECT
• Sub-massive PE
- How to assess
- Pragmatic approach to decision thrombolysis
- Catheter directed thrombolysis
Up date in Diagnostic Imaging
Get the diagnosis right at the
start…
Standard V/Q scan
• Planar images
• Camera is stationary over the patient
• Acquires an image from this one angle,
like an x-ray
Planar image
SPECT
• Single Photon Emission Computed
Tomography
• Camera rotates around the patient, gets
images from a variety of angles
• Can then reconstruct 3-dimensional view
SPECT – how it works
• Camera head rotates around patient
Normal SPECT image
PERF
PERF
PERF
VENT
VENT
VENT
A
X
I
A
L
C
O
R
O
N
S
A
G
I
T
Abnormal
PERF
PERF
PERF
VENT
VENT
VENT
False positives?
False positives
Consolidation
Dose of Radiation
• Worst case scenario:-
• Perfusion (technetium): 2.2mSv
• Ventilation (krypton): 0.29mSv
• Ventilation (technetium): 1mSv
• 1mSv: 1 in 20,000 chance of fatal cancer
• 1 year in London: 2 mSv
• 1 year in Cornwall: 8 mSv
CTPA… Plus
• New Scanners – dual tubes & “voltages”
• Can detect specific – eg calcium, iodine
• Measure volume of iodine per pixel –
shown in colour
• Dose of radiation same or even less….
• Need less contrast (eg renal failure)
Iodine map= perfusion map
- marked decreased perfusion in
left lung
Dual energy CTPA- CTPA image
only- left pulm art filling defect
Fused iodine and CT
Virtual non-contrast CT- allows us
to remove iodine and we can
therefore see if an intravascular
mass virtually “enhances”
Definitions of PE
Massive PE
• SBP < 90 mmHg or drop of >40 mmHg
• >15 mins
• with no other cause
• Up to 5-10% of patients
• Mortality – high (15-58%)
Massive PE - Treatment
• Resuscitation
• “Full Dose” systemic thrombolysis
• tPA – 10mg bolus, 90mg / 2 hours
• Risk of major bleeding (6-20%)
• Intracranial Haemorrhage (2-6%)
• ….But outweighs risk of death from PE
Sub-massive PE
• Not hypotensive but…
• Evidence of right heart dysfunction
• Evidence of myocardial injury
– elevated Troponin , BNP
• Confirmed large clot burden – CTPA (V:Q)
• Mortality or “Adverse Events” 3-25%?
So why not thrombolyse too?
(Excellent Pro/Con Debate at this meeting 2 years ago… Overwhelming NO!)
And Thorax Pro/Con Debate
So why not thrombolyse too?
(Excellent Pro/Con Debate at this meeting 2 years ago… Overwhelming NO!)
And Thorax Pro/Con Debate
“Adverse Events” from
Sub-Massive PE
American Guidelines – Chest 2016
• Sub-massive PE
*23. In selected patients with acute PE who deteriorate
after starting anticoagulant therapy but have
yet to develop hypotension and who have a low
bleeding risk, we suggest systemically administered
thrombolytic therapy over no such therapy
(Grade 2C).
American Guidelines – Chest 2016
*23. In selected patients with acute PE who deteriorate
after starting anticoagulant therapy but have
yet to develop hypotension and who have a low
bleeding risk, we suggest systemically administered
thrombolytic therapy over no such therapy
(Grade 2C).
….Dose not suggested
American Guidelines – Chest 2016
MOPETT Trial
• Concept of “Safe Dose Thrombolysis”? • Cardiac output – Brain 15%, Heart 5%, Pulmonary 100%
• tPA - 10mg bolus
• tPA - 40mg/2 hours (0.5mg/kg if <50kg)
MOPETT Trail
MOPETT Trail
“PERT”
A Pragmatic British
Alternative…
And applicable to DGH as
teaching hospitals alike…
PE Lysis Team- “PELT”
• Chest Physicians
• Critical Care
• Haematologists
• Interventional Radiology
• (Obstetric Physician)
PE Lysis Team- “PELT”
• Chest Physicians
• Critical Care
• Haematologists
• Interventional Radiology (pt bleeding risk)
• (Obstetric Physician)
Sub-massive PE
• Not shocked but…
• Evidence of right heart dysfunction
• Evidence of myocardial injury
– elevated Troponin , BNP
• Confirmed large clot burden – CTPA (V:Q)
• Mortality or “Adverse Events” 3-15%?
Sub-massive PE
• Not shocked but…
• Evidence of right heart dysfunction*
• Evidence of myocardial injury
– elevated Troponin*, BNP*
• Confirmed large clot burden* - CTPA (V:Q)
• Mortality or “Adverse Events” 3-15%....
• Predictors* – both +ve and -ve
PE Lysis Team- “PELT”
• Initial Clinical Assessment
• ECHO
• Bilateral leg Dopplers
• Bleeding risk (NB age, Pulmonary infarction)
PE Lysis Team- “PELT”
• Initial Clinical Assessment
• ECHO
• Bilateral leg Dopplers
• Bleeding risk (NB age, Pulmonary infarction)
• Serial Assessment – review progress
• Patient involvement in decisions/consent
• …..then you make a TEAM judgement
Local Protocol for Sub-Massive PE
• Team decision
• Done in level 2 or 3
• Systemic “half dose” first line
• Catheter direct Thrombolysis for
- bleeding risk (eg post surgery)
- Second line (post systemic, including massive PE)
- “Older Clot”?
• (Local outcome very good… thus far)
Catheter Directed Thrombolysis
• Interventional Radiology
• Time is situ 12-24 hours
• Infuse tPA 0.5-1mg per hour
• Lower total dose
• Can be bilateral (and each side “adjusted”)
• Still risk of bleeding and arrhythmia
50
EKOS™ Endovascular System Features
―
―
―
51
Acoustic Pulse Thrombolysis™
treatment Mechanism of action
Fibrin Separation Ultrasound separates fibrin
without fragmentation of emboli
Active Drug Delivery Drug is actively driven into clot by
“Acoustic Streaming”
EKOS™ Acoustic Pulse Thrombolysis™ treatment is a minimally invasive
system for accelerating thrombus dissolution.
Question?
• 34yo lady, 33/40
pregnant. V:Q –
Significant bilateral
PEs. BP 115/78.
Tachy 110, 60% O2,
RR24, sats 91%. Has
had 2/7 full dose
LMWH, no better,
moved to ICU for
“closer monitoring”
• A: Continue Fragmin
• B: iv heparin
• C: Cather Directed
Thrombolysis
• D: 100mg tPA
• E: 50mg tPA
• F: Give all info to
patient and let her
decide
Question?
• 34yo lady, 33/40
pregnant. V:Q –
Significant bilateral
PEs. BP 115/78.
Tachy 110, 60% O2,
RR24, sats 91%. Has
had 2/7 full dose
LMWH, no better,
moved to ICU for
“closer monitoring”
• A: Continue Fragmin
• B: iv heparin
• C: Cather Directed
Thrombolysis
• D: 100mg tPA
• E: 50mg tPA
• F: Give all info to
patient and let her
decide
Summary
• Advances in diagnostics to enable correct
diagnosis at the start
• Advances in TEAM decisions for the more
severe PEs to enable improved morbidity
and mortality