Transcript Arrhythmia: Tests, Devices, Physiologists

Arrhythmias:
Tests, Devices, Physiologists
Jane Eldridge
BSc(Hons) Dunelm, ACP,
BSc(Hons) Clin. Phys., MRCCP
Lead Cardiac Physiologist Cardiac Catheter Labs
West Herts NHS Trust
Tests for Arrhythmias
 ECG, with rhythm strip
 Carotid sinus massage (Hypersensitive carotid sinus syndrome)
 24 hour ECG holter (a.k.a. tape analysis)
 48 hour to 7 day ECG holter (for less frequent symtoms)
 Implanted ECG Loop Recording Device (Reveal™ for very
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infrequent symptoms)
Treadmill test for HR response (chronotropic incompetence) and
exercise-induced arrhythmia
Echocardiography (structural causes for arrhythmia)
Tilt-testing (pre-syncope / syncope)
Electrophysiology Study (EPS) for accessory pathways and
circular or re-entry arrhythmias potentially suitable for ablation
ECGs
 Excellent diagnostic tool
 Non-invasive, quick, easy and
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cheap!
Recommend rhythm strip also
Beware of auto-reporting!
Good skin prep and electrode
contact for clear & clean ECG
Essential to have good electrode
positioning to be useful as a
diagnostic tool
Carotid sinus massage (CSM)
to provoke arrhythmia eg
asystole
ECG Holters / Tape analysis
 Del-Mar Reynolds “Lifecards”
 Symptoms button ± diary
 Each card loaded into specialist
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tape analyser software
Each 24hr tape takes approx 30
mins to analyse by experienced
Cardiac Physiologist
All recorded ECG is examined
Correlation of symptoms very
important
Report generated by Cardiac
Physiologist
Significant arrhythmias reported
immediately to Cardiologist
Implantable ECG Loop Recording
Devices (ILRs): Reveals
 Implanted left pectoral region
 Programmable criteria for auto
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recording eg brady @ 30bpm
Activator given to patient to press
if symptomatic
Pt comes into clinic for regular
(usually 3 monthly) downloads of
device by Cardiac Physiologist
Can only be downloaded with
specialist programmer
Pt advised to contact dept ASAP if
they have an event so the device
can be downloaded
Devices cost approx £1250
Battery lasts for approx 2-3 yrs
Exercise testing for arrhythmia &
chronotropic response
 Looking for appropriate HR
response to exercise (and any
exercise induced arrhythmia)
 Conducted by 2 Cardiac
Physiologists (who should have
ILS or ALS certificate) using
treadmill
 Terminated for observed
arrhythmia, symptoms or poor
HR response
 Report generated and printouts
of arrhythmias observed
Head-up Tilt Testing for Neurally
Mediated Syncope
 Warm, quiet, low lighting room
 Attempt to provoke event. BP and HR
closely monitored by Cardiac
Physiologist (who should have ILS or
ALS certificate)
 Significant HR drop / sinus pause /
asystole (cardioinhibitory response) may
be suitable for pacemaker implant
 For sudden heart rate drops we may use
specialised algorithms on the pacemaker
known as “accelerations”
 Loss of vascular tone with blood
pressure drop (vasodepressor response);
Pacemaker may be unsuitable
Echocardiography to identify
structural causes for arrhythmia
 Non-invasive test that gives
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vast array of information
Cardiac dimensions
Cardiac function
Valve structures
Valve functions
Shunts & abnormalities
Cardiomyopathies
Dysynchrony
Approx 40 mins per test
Highly Specialist Cardiac
Physiologist required
Electrophysiology study (EPS)
 Several specialised catheters
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inserted into different areas of the
heart
Electrical activation pattern mapped
Accessory pathways, circular routes
or re-entry circuits identified
Carefully controlled radiofrequency
ablation across faulty pathways
administered by Cardiac
Physiologist
Expensive, very specialised
equipment and staff, timeconsuming procedure (2-4hrs)
Can be curative
Indications for device implant
 Pacemakers
– SSS, AVB, CHB, CI, Chronic AF with bradycardia, Symptomatic
Bifasicular block / Trifasicular block, Neurally mediated syncope
(CSS, VVS, situational syncope)
 Biventricular pacemakers (CRT-P)
– CHF with LBBB & low EF(<35%), dysynchrony on echo, long PR
with poor haemodynamics, NYHA class IV
 Implantable Cardiac Defibrillators (ICDs)
– Primary indication; significant risk of life threatening arrhythmia eg
Long QT, Brugada, DCM, Post MI with NSVT & poor EF
– Secondary indication; survival of a VT or VF arrest
 Biventricular ICD (CRT-D)
– CHF with LBBB & low EF(<35%), dysynchrony on echo, long PR
with poor haemodynamics, NYHA class III or IV, prior MI with risk
of SCD
Pacemakers
 Single (atrial or ventricular) or dual chambered
 Pacemakers now store lots of information that can
be reviewed at follow-up eg % time spent in AF
 Now extremely programmable with many
features & algorithms eg (a few examples)
– Rate responsiveness (HR in response to activity)
– AF suppression (pacing the atria)
– Rate drop acceleration response
 Must be regularly followed up in clinic (at least
once a year) to assess function and battery
 Requires highly specialist equipment and Cardiac
Physiologists for implant and follow-up
 Device costs vary from approx £1500 to £3500
Biventricular pacemakers
 Also known as Cardiac Resynchronisation
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Therapy (CRT)
May be patients for whom chronic RV
pacing is becoming problematic
3 leads usually (atria, RV and LV)
Pacing both ventricles in a timed manner
allowing resynchronisation
Optimises cardiac output by allowing
appropriate ventricular filling and coordinated contraction
CRT devices cost about £4000 to £8000
Implantable Cardiac Defibrillators
ICDs
 Ability to DC shock for ventricular
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tachyarrhythmias eg VF and VT
700-800 Volts or 30-40 Joules
Most now can also deliver ATP (antitachy pacing) to attempt to reduce
need for shock therapy
Extremely complex devices that have
many programmable features
Set-up and management is often quite
tricky eg in the presence of AF
Most devices are also able to pace
although most patients do not have a
primary pacing indication
ICD systems cost approx £8,000 to
£15,000
Biventricular ICDs!
 Also known as “CRT-D”
 2 ventricular leads for cardiac
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resynchronisation
Shock leads for defibrillation
Highly complex, very
programmable devices
Highly specialist equipment and
Cardiac Physiologists required
Devices cost up to £15,000
Specialist Cardiac Staff
 Cardiographers
– Basic qualifications / certification
– ECGs, application and removal of tapes and monitors
 Cardiac Physiologists
– Qualified to BSc (Hons) Clinical Physiology (4 yrs) or equivalent
– Registered with RCCP (voluntary, soon compulsory)
– ECG analysis & interpretation, tape analysis, exercise treadmill testing,
RACPC, tilt testing, cardiac catheterisation & intervention
 Highly Specialist Cardiac Physiologists
– Post registration specialisation in echo or devices and / or
electrophysiology (a further 2-4 yrs)
– Higher qualifications eg BSE, NASPE or HRUK accreditation
– Independent echo reporting, device management (implant and follow-up)
and or electrophysiology study interpretation and treatment
Guidelines for practice
 National standards for practice:
– National Institute of Clinical Excellence (NICE)
– British Cardiovascular Society (BCS) publishes guidelines for
national standards of practice and has affiliations of the following
groups:
– The Society for Cardiological Science and Technology (SCST)
– Registration Council of Clinical Physiologists (RCCP)
– British Society of Echocardiography (BSE)
– Heart Rhythm UK (HRUK) for Devices and EP
– Arrhythmia Alliance (AA) – for info leaflets
– British Heart Foundation (BHF) – for info booklets
 Local guidelines and competancies in Cardiology Dept
Any questions?
Old method for
taking an ECG!