Download The 80 Lead ECG Body Surface Map: Can We Detect More STEMI

The 80 Lead ECG Body Surface Map:
Can We Detect More STEMI Than
with a 12 Lead ECG?
James Hoekstra MD
Professor and Chairman
Department of Emergency Medicine
James Hoekstra, MD
Disclosure Statement
Affiliation/Financial Interest – Corporate Organizations, Manufacturers, Providers
Consultant
Heartscape Technologies, Sanofi,
Schering Plough
Grants/Research Support
Heartscape Technologies
Stock Shareholder
None
Other Financial or Material Support
None
Speaker’s Bureau
BMS, Sanofi, Schering Plough,
Genentech
Employee
None
Initial Chest Pain Assessment
Risk determined in the ED by:
• Assessment of anginal symptoms
• Physical examination
• CAD risk factors
• Cocaine/methamphetamine use
• Electrocardiogram
• Markers of Infarction/Ischemia
“Limitations” of the 12-Lead ECG
• Posterior MI
• Right Sided MI
• High Lateral MI
• Inferior MI
• LBBB and STEMI
• In an all-comers CP population,
98% of ECGs are nondiagnostic
TRITON subset analysis evaluated
occurrence of occult STEMI
• TRITON–TIMI 38 evaluated prasugrel
vs. clopidogrel in 13,608 patients
undergoing PCI
– Follow up duration: 6-15 months
• Post-hoc analysis: 1,198 patients with
isolated anterior precordial ST
segment depression (>1 mm) on 12lead ECG
– STEMI defined as TFG 0/1 and
positive troponin
Gibson CM. Circulation. Vol 118, Suppl. 2, 2008, presented at AHA, Nov, 2008 .
95% of occult STEMI were missed in
TRITON–subset analysis
• 26.2% (314/1198) of patients
with isolated anterior precordial
ST segment depression >1mm
had a “STEMI”, TFG 0/11
• 4.5% (14/314) of “STEMIs” were
interpreted as STEMI by
investigators1
• Median time to PCI for patients
with STEMI was 29.4 hours1
• No patient with an occluded
artery had an ECG to PCI time <
6 hours
1.Gibson CM. Circulation. Vol 118, Suppl. 2, 2008.
1198 patients with isolated
anterior precordial ST segment
depression1
CULPRIT ARTERY IN “STEMI”* PATIENTS
60%
Patients
50%
48.4%
40%
33.8%
30%
17.8%
20%
10%
0%
LCx
n=152
* TFG 0/1 in culprit artery
Positive cardiac biomarkers
LAD
RCA
n=106
n=56
Occult STEMI patients had higher 30-day
rates of Death/MI
Occult STEMI
in TRITON subset analysis1
1.Gibson CM. Circulation. Vol 118, Suppl. 2, 2008.
Increased death/MI
in patients with occult STEMI1
The 80-Lead ECG and
Body Surface Mapping
• More leads investigate more areas
of the heart
• Mapping allows computer generated
pictures of ischemic areas
• Computerized readings allow
for more accurate interpretation
The PRIME ECG® Technology
Single-patient Disposable Vest
• Easily-applied, self-adhesive plastic strips
containing 80 data collection points
• Strips allow analysis of the heart’s electrical
activity with 360 degrees of spatial resolution
• Data from the 80 leads are processed into
3-D color maps for easy visualization
Placement of the 80 Leads Provides
a Comprehensive View of the Heart
• 64 anterior and 16 posterior leads
• Conventional V leads 1-6 are marked
PRIME ECG® Allows You to Investigate
Data from All 80 Leads
• View a single 10-second recording for leads of
interest
PRIME ECG® Provides a 3-D, Color-coded,
Anatomically-referenced Visualization of the Injury
ST-segment elevation and depression
are translated into colors:
Red = ST elevation
Blue = ST depression
Green = No deflection
3-D Color Representation
of the 80-Lead ECG
Interactive Algorithm Suggests Diagnosis
Algorithm
Result on
Presentation
Pop-up Displays
Underlying ECG
Trace and Value
Anterior
Posterior
• Data from the 80 leads are processed by an interactive algorithm
that suggests findings and can provide important details necessary
to achieve a timely and accurate diagnosis
• Represents an extension of conventional ECG technology, resulting
in a fast learning curve with minimal training time
PRIME ECG® Detected More Acute MIs
Without Loss of Specificity
In a meta-analytic composite of three separate studies, PRIME showed relative
improvement of 53% and absolute improvement of 23% over the 12-lead
Ornato, n=481 (1)
70%
40%
30%
McClelland, n=103 (2)
25%
80%
70%
20%
45%
60%
40%
10%
PRIME
Pretest probability of MI: 22%
12-Lead sensitivity: 25%
PRIME sensitivity: 34%
Relative improvement: 33%
Absolute improvement: 8%
40%
12-Lead
•
•
•
•
•
57%
50%
30%
12-Lead
90%
80%
60%
50%
•
•
•
•
•
64%
34%
Owens, n=294 (3)
PRIME
Pretest probability of MI: 51%
12-Lead sensitivity: 45%
PRIME sensitivity: 64%
Relative improvement: 42%
Absolute improvement: 19%
12-Lead
•
•
•
•
•
PRIME
Pretest probability of MI: 62%
12-Lead sensitivity: 57%
PRIME sensitivity: 80%
Relative improvement: 42%
Absolute improvement: 24%
(1) Ornato JP, et al. Amer J Cardiol. 2002;39(5):332A
(2) McClelland AJ, et al. Amer J Cardiol. 2003;92:252-257
(3) Owens CG, et al. J Electrocardiol. 2004;37:223-232
The OCCULT MI Trial Design
• Multicenter prospective observational
trial of 80-lead mapping ECG versus
12 lead ECG
• 12 academic EDs, 1830 patients
• Moderate-to-high risk chest pain
• Clinicians blinded to result of 80L,
treatment by standard of care
• Outcomes: Door to Sheath Time and
MACE in patients with STEMI by 80lead-only versus STEMI by 12 lead
ECG
OCCULT MI 12-lead STEMI Population
1,830 patients enrolled
91 diagnosed as STEMI by site final diagnosis
84 underwent
cardiac catheterization
and had DTST available
1,739 not diagnosed as STEMI
7 did not undergo cardiac catheterization:
2 patients were DNR and aggressive medical measures were withheld
1 refused cardiac catheterization
1 deemed not to be a candidate for cardiac catheterization
1 patient had GI bleed and was monitored in the CCU
1 patient expired prior to cardiac catheterization
1 patient treated conservatively due to normal echocardiogram
OCCULT MI 80L-only STEMI Population
1,830 patients enrolled
316 Troponin positive
75 site-determined STEMI
241 not site-determined STEMI
210 with evaluable 80-lead PRIME ECG
25 PRIME-only STEMI
1500 Troponin negative
+14 missing
27 with inevaluable 80-lead PRIME ECG
+4 missing
185 NOT PRIME only STEMI
14 with DTST data available
11 did not undergo cardiac catheterization
Tn positive defined as peak level over
site normal range, precath
OCCULT MI Outcomes: Cath Strategy
% Angiography
Door to Sheath Time
12L n=84
80L, n=14
100
80
%
p<0.0001
1002
1200
92%
1000
800
60
56%
40
12L
80L
Min 600
400
20
12L
80L
54
200
0
0
% Angiography
Door To Sheath Time
(median, minutes)
% Revascularization: 89% vs 78%, p=0.48
OCCULT MI: Clinical Outcomes
p=0.45
14
12
12.5 %
10
%
8
6
8.0 %
12L, n=88
80L, n=24
4
2
0
% Death/MI
Peak TnI: 19.7 versus 10.3 ng/dl, p=0.37
OCCULT MI Conclusions
• 80 lead map ECG identifies 27.5%
higher number of STEMI patients than
12 lead ECG
• 80 lead-only STEMI patients received
conservative and significantly
delayed catheterization strategy
• 80 lead-only STEMI patients have
clinical and angiographic outcomes
similar to 12 lead STEMI
• The 80 lead ECG identifies a patient
population which may benefit from
more aggressive care
Who is Eligible for PRIME ECG?
• High risk patients, ongoing pain
• Abnormal, but nondiagnostic ECG
• ST Depression (25% missed STEMI)
• LBBB
• Known CAD, PCI, High TIMI Score
• Elevated Tn
Summary
• The 80-lead technology increases the sensitivity
and specificity of the ECG for MI
• The PRIME system allows for ease of ECG
acquisition in clinical care
• OCCULT MI trial confirms that PRIME can
identify a high risk patient that may benefit
from more aggressive therapy.