Stress Echo: Role in Pre-Operative Assessment

Dr. Rachael James MD, BSc, FRCPConsultant CardiologistgSussex Cardiac Centre

Brighton

T lk O liTalk Outline

Types stress echoyp

Dobutamine stress echo for ischaemia

Role stress echo in peri-operative work up

Does revascularisation affect peri operative outcome Does revascularisation affect peri-operative outcome

S E hStress Echo Introduced 1979 Introduced 1979

2D echo combined with a pharmacological, physical or electrical stress

Versatile technique primarily used for detecting ischaemia & determining prognosis

ESC Cl IC i di ti hi h i k ti t 3 li i l f t ESC Class IC indication high risk patients >3 clinical factors

Diagnostic endpoint for detection myocardial ischaemia: Transient regional wall motion abnormality distal to obstructiveTransient regional wall motion abnormality distal to obstructive

coronary artery stenosis

Other uses: Assessing presence myocardial viability Assessing presence myocardial viability Assessing severity valve disease Occult pulmonary hypertension

T S E hTypes Stress EchoI h i d

Pharmacological Dobutamine Ischaemia

Ischaemic cascade

Low flow low gradient AS Myocardial viability

Physical (bike or treadmill) Physical (bike or treadmill) Ischaemia Valve disease

Mitral regurgitation Mitral stenosis Aortic regurgitation

Electrical (PPM) Ischaemia

E i E h f I h iExercise Echo for Ischaemia Technically challenging

For treadmill test need patient quickly on the couchquickly on the couch

Upright bike images can be tricky

Increased chest wall movement

Hyperventilation

Limited to patients who can Limited to patients who can exercise

Higher inter-observer variability comparedvariability compared Dobutamine stress echo

Lower diagnostic accuracy

Stress Echo Patients with PPMPPM

C d t t t i PPM Can do stress test via PPM

Don’t get inotropic effect Dobutamine &required targetDobutamine &required target heart rate may exceed device

If possible use Dobutamine butIf possible use Dobutamine but may need adjust device upper rate

Generally more tricky studies: Wall motion abnormalities if

pacedp Particularly if switch from paced

to unpaced during the stress test ECG may be interpretable ECG may be interpretable

D b i S E hDobutamine Stress Echo Ischaemia

Investigation chest pain in patients intermediate risk

Positive DSE investigation exertional breathlessness

patients intermediate risk Assessment known coronary

stenoses borderline severity Risk stratification non cardiac

surgery

B fit f ll TTE Benefit full TTE

No ionising radiation

Less good investigation exertional breathlessness & no ischaemic historyischaemic history

Argulian E Eur J Echocardiogr 2013

H D W D I ?How Do We Do It? O it b t bl k Dilti Omit beta-blockers, Diltiazem,

Verapamil 48 hours

Avoid heavy meal / caffeine onAvoid heavy meal / caffeine on the day

If windows adequate (95% ti t ) & fpatients) & no cause for

symptoms found: Widespread resting regional

wall motion abnormalitieswall motion abnormalities Severe PHT

iv access & 0.5mL iv contrast agent Sonovue

H D W D I ?How Do We Do It?

Baseline Images

D b i S E hDobutamine Stress EchoC ti 12 l d ECG l d iti ill b b l Continuous 12 lead ECG – lead position will be abnormal

Images: low dose 5micg/Kg/min low dose 5micg/Kg/min mid dose 20micg/Kg/min peak 40micg/Kg/min +/- Atropine

Aiming target heart rate: 220-age – 85%

End points:End points: Completing protocol & attaining target heart rate at peak dose Development new regional wall motion abnormalities W i i ti RWMA Worsening pre-existing RWMA Failure develop hyperdynamic response Adverse events e.g. VT Chest pain / ECG change

R D b iResponse to DobutamineNormal Abnormal

> 2 adjacent myocardial

Improvement LV function

2 adjacent myocardial segments worsen function Normal to hypokinetic or

akinetic Reduction end systolic cavity

size Hypokinetic to akinetic /

dyskinetic

Early vs late All LV myocardial segments normal & become hyperdynamic

Early vs. late

Minimal myocardial segments vs. widespread

Failure develop hyperdynamic function Sudden deterioration LVSudden deterioration LV

function ?? LMS

Contraindications Dobutamine S E hStress Echo

Poor echo windows (5% patients BSUH)

Unable to lie in left lateral position

P l t ll d t i l Poorly controlled atrial arrhythmia

Uncontrolled hypertensionUncontrolled hypertension (systolic >220 or diastolic >120mmHg)

A t MI < 6 k Acute MI < 6 weeks

Recent ventricular arrhythmia

P di i V l DSEPredictive Value DSE Hi h lti l di D b t i h i Higher multivessel disease

(MVD) compared single vessel

Better for LAD territory than

Dobutamine has primary impact contractility

Usually target heart rate isBetter for LAD territory than posterior circulation

Exercise echo:

Usually target heart rate is reached

DSE detect 93% patients >50% t t i Sensitivity MVD

85-100% Sensitivity SVD

>50%coronary artery stenosis

Comparable to nuclear imaging

59-94%

Dobutamine increases heart rate & BP

ag g No soft tissue artifact Sensitivity MVD

91 98%rate & BP 91-98% Sensitivity SVD

66-95%

Armstrong WF J Am Coll Cardiol 2005, Sicari R J Am Coll Cardiol 2003, Huang PJ Cardiology 2004, Marwick T J Am Coll Cardiol 1993

F l P i i S E hFalse Positive Stress Echo I h i h d ti Ischaemia when reduction

coronary flow reserve (CFR)

In absence coronary artery

Mortality patients false positive & true positive DSE

In absence coronary artery disease, CFR reduced Microvascular disease

(syndrome X)(syndrome X) LVH (hypertension)

Increased incidence falseIncreased incidence false positive stress echo women

False positive DSE not without l t i klong term risk

From J Am Soc Echocardiogr 2010

N i DSENegative DSE

Normal stress echo event rate 3D probability cardiac event over 5

t ti i hrate 0.1% per year non fatal MI 1.1% cardiac death

years post negative exercise echo

Also have prognostic factors LV function Exercise capacity

Mazur W J Am Soc Echocardiogr 2003

P i O i MIPeri-Operative MI

Either ‘conventional’ MI

Coronary artery plaque rupture Thrombus formation Vessel occlusion Vessel occlusion

Peri-operative stress response: Abnormal cytokine response Catecholamine surge Platelet activation Reduced fibrinolytic activity Vasospasm

Or sustained myocardial supply / demand imbalance

Wh D S E hWhy Do a Stress Echo Pre op risk stratification: Markers increased risk: Pre-op risk stratification:

Assess risk planned surgery Direct pre-op investigation /

intervention

Markers increased risk: Angina / prior MI Prior heart failure Severe renal impairment

Inform patient about risk

Main evidence intermediate & high risk vascular surgery

p Poor functional capacity Severe valve disease Inducible ischaemia on functional

testing Up to 60% patients peripheral

vascular disease have underlying coronary disease

testing

Peri-op cardiac events low patients few clinical variables

Presence peripheral vascular disease associated with 6.6-fold increase relative risk death from coronary disease

few clinical variables

Inducible ischaemia DSE predictive peri-op cardiac events (death/MI)

N l t h 100% ti High risk morbidity & mortality

patients with peripheral artery disease undergoing surgical procedures

Normal stress echo 100% negative predictive power

procedures

Poldermans Am Coll Cardiol 1995, Lane J Vasc Surg 1991, Boersma JAMA 2001

N V lNon Vascular surgery Less evidence

Likelihood coronary disease l l ti

Dobutamine Stress Echo has incremental value over clinical (Eagle index), ECG &

more general population coming for non vascular surgery lower

standard echo variables in non vascular surgery

Normal stress echo 100% Problems relying on cardiac

symptoms in orthopedic population

Normal stress echo 100% negative predictive value

We can identify patients at population y pincreased risk of complication

E id th t i t i Evidence that intervening on coronary disease is elusive

Das MK J Am Coll Cardiol 2000

D I i H l ?Does Intervening Help? DECREASE V & CARP trials patients DECREASE-V & CARP trials patients

undergoing vascular surgery

Revascularisation not associated mortality benefit

Incidence All-Cause Mortality or MI Patients Inducible Ischaemia

DECREASE-V trial patients > 3 risk factors underwent DSE or stress nuclear imaging inducible ischaemia

only 86% completely revascularised

Short time interval between intervention & surgery

29/7 (13 65) CABG 29/7 (13-65) CABG 31/7 (19-39) PCI

Trial not powered to show difference between medical Rx & revascularisationbetween medical Rx & revascularisation in high risk patients

Deaths patients post revascularisation from ruptured AAA before planned surgery

DECREASE-V studyLight line medical treatmentDark line medical Rx + Revascularisationsurgery

Poldermans J Am Coll Cardiol 2007

D I i H l ?Does Intervening Help? CARP trial – nuclear stress testing

Patients stable coronary disease randomized to medical treatment or revascularisation

Coronary Artery Revascularization Prophylaxis trial

revascularisation

Post vascular surgery no difference in-house mortality or MI

Non significant trend toward benefit revascularisation in high risk patients

All male

But high risk patients were excluded: LMS >50% Severe AS LV EF <20% LV EF <20%

Doesn’t help us about role of screening high risk patients and revascularisation

McFalls NEJM 2004

D I i H l ?Does Intervening Help? F t l MI i i d ft Fatal MI peri-op period often

involves unstable plaque & plaque disruption

Intervening on stable coronary lesion may not add to optimal medical therapyto optimal medical therapy

PCI & CABG associated acute inflammatory response

Increased stent thrombosis rate ulcerated lesions & early post procedurepost procedure

Dangas Circulation 2011, Daemen Lancet 2007

Off label/real world DES thrombosis Rotterdam/Bern Registry

Wh T d ?What To do? No strong evidence

Methodological issues with

Coronary intervention symptomatic patients (ESC IA)Methodological issues with

studies

Some surgery very early post

IA)

Prophylactic revascularisation

intervention / CABG

Surgery (cardiac & non cardiac) associated systemic

asymptomatic patients prior to high risk surgery (ESC IIB)

Prophylacticcardiac) associated systemic inflammatory response & pro-thrombotic state

Prophylactic revascularisation patient found to have LMS / proximal severe coronary disease

Risk intervention itselfsevere coronary disease following stress echo

Poldermans Eur Heart J 2009

ACC/AHA G id liACC/AHA Guidelines

J Am Coll Cardiol 2007

A Q i ?Any Questions?