TILTTABLE TESTING

1
TILT-TABLE TESTING CAROTID SINUS
HYPERSENSITIVITY

• BELLA RICHARD
• ASSOCIATE SPECIALIST
• NEVILL HALL HOSPITAL

2

• Syncope is defined as a sudden, brief transient
  loss of consciousness associated with loss of
  postural tone with spontaneous recovery
• Syncope is a big problem
• Great cause of anxiety among patients, carers and
  treating physicians
• 3 AE visits annually
• 6 hospital admissions annually
• May be the only warning episode before sudden
  cardiac death.
• Common cause of unexplained elderly falls

3
CAUSES OF SYNCOPE

• CVS -13.2
• UNKNOWN CAUSES -31
• STROKE/TIA - 4.3
• SEIZURE DISORDER - 7.2
• VASOVAGAL - 20
• ORTHOSTATIC CAUSE -9
• MEDICATION -6.3
• OTHER CAUSES -9.5

4
TILT TABLE TESTING

• Ancient test-used in experiments to study bodys
  response to posture
• Since 1986- used as an evaluation tool for
  syncope
• Now gold-standard

5
PHYSIOLOGICAL BASIS

• On standing 300-800mls of blood is displaced
  downwards
• In seconds mechano-receptors in the vasculature
  compensate by increasing sympathetic tone -
  vasoconstriction and increased cardiac output
• Orthostatic stabilisation occurs within 60 secs
• Neurally mediated response

6

• Tilt table test examines this neuro-cardiovascular
  response in a maximally controlled environment.
• Tilt angle -700 angle of maximal passive
  orthostatic stress
• Tilt duration 10min supine followed by 40 min
  tilted.
• ?pharmacological stimulation- nitroglycerine,
  isoproterenol, epinephrine ( increases
  sensitivity at the expense of specificity)

7
INDICATIONS AND CONTRA INDICATIONS FOR HUT

• INDICATIONS -, RECURRENT SYNCOPE OR PRESYNCOPE
  
  
• SINGLE SYNCOPE WITH SERIOUS CONSEQUENCES
• AUTONOMIC FUNCTION TESTS
• SITUATIONAL SYNCOPE
• OH
• POTS
• CAROTID SINUS HYPERSENSITIVITY.
• CONTRAINDICATIONS - SEVERE LV OUTFLOW
  OBSTRUCTION, SEVERE CORONARY /CAROTID STENOSIS

8
Five responses

• Neurocardiogenic syncope symptomatic sudden
  drop in BP after 10 mins associated with
  bradycardia.
• These patients are well between turns.

9

• Dysautonomic response - gradual
  decrease in BP to a hypotensive level leading to
  LOC. HR will not rise significantly.
• These patients have other features like abnormal
  sweating, thermal intolerance, bowel symptoms.
• POTS - mild form of autonomic dysfunction in
  which excessive increase in HR cannot compensate
  for low peripheral vascular resistance. Patients
  increase HR to gt30/min in 10 min of upright
  posture

10

• Patients have near syncope, palpitations, fatigue
• Cerebral syncope - Research centres doing TTT and
  transcranial dopplers found a small number of
  patients having cerebral vasoconstriction with no
  hypotension and bradycardia.
• Psychogenic or psychosomatic response - patient
  has vague symptoms but no findings. Patients
  often have coexisting psychiatric disorders.

11
CAROTID SINUS HYPERSENSITIVITY.

• COMMON CAUSE OF SYNCOPE IN ELDERLY PATIENTS
• UNDIAGNOSED IN UPTO 50 OF PATIENTS.
• NOT EASILY REPRODUCIBLE.
• NEEDS REPEATED TESTING TO ENSURE PICK UP.

12
(No Transcript)
13

• POSITIVE TEST COULD BE
• VASODEPRESSOR,
• CARDIOINHIBITORY OR A
• MIXED RESPONSE.
• DIAGNOSE IF gt 3SECS ASSYSTOLE OR 50 MM HG DROP
  IN SYSTOLIC BP.
• DUAL CHAMBER PACING IN THESE PATIENTS PRODUCES
  SYMPTOMATIC RELEIF IN 90 PATIENTS.
• OVERLAP EXISTS BETWEEN CSH AND VASOVAGAL
  SYNCOPE.

14
INDICATIONS AND CONTRAINDICATIONS FOR CSM

• INDICATIONS - OLDER PATIENTS WITH SYNCOPE ,
  UNEXPLAINED FALLS
• CONTRAINDICATIONS - TIA / MI /STROKE IN THE PAST
  3 MONTHS
• PREVIOUS VF ARREST
• CAROTID BRUITS / CAROTID STENOSIS gt 70
• LESS SEVERE CAROTID STENOSIS ONLY SUPINE CSM

15
PROTOCOLS

• PASSIVE DRUG FREE TILT
• 40 MIN AT 70 DEGREES HEAD UP TILT
• REST PATIENT FOR 20 MIN PRIOR TO TESTING
• CAROTID SINUS MASSAGE BEFORE TILTING AND AFTER 40
  MIN HEAD UP TILT
• CONSENT OBTAINED FOR CAROTID SINUS MASSAGE

16
(No Transcript)
17
(No Transcript)
18
Staffing levels

• TWO OPERATORS MUST BE PRESENT OF WHICH ONE MUST
  BE TRAINED IN ACLS
• RESUSCITATION TROLLEY AVAILABLE ALWAYS
• TESTS ARE DONE IN THE CARDIO-RESPIRATORY DEPT.
• ONE AFTERNOON SESSION PER WEEK
• NOT MORE THAN THREE PATIENTS PER SESSION

19
Syncope in the Older AdultDiagnostic Evaluation

• Pursue witness accounts when possible
• Include in history taking
• social circumstances, injurious events, impact of
  events on confidence, ability to perform ADLs
  independently
• Determine timing of syncope occurrence
• orthostatic hypotensive events usually occur in
  the AM
• Association with meals, medications, nocturnal
  micturition, etc.
• Detailed medication history
• Co-morbid diagnoses (especially Parkinsons,
  diabetes, anaemia, hypertension, ischaemic heart
  disase, heart failure)

20
Syncope in the Older AdultExamination

• Assessment of neurological and locomotor systems
• Including observation of gait and standing
  balance (eyes open eyes closed)
• Determine if cognitive impairment is present
  (mini-mental state examination)

21
Syncope in the Older AdultInvestigations

• The diagnostic evaluation should include the same
  basic components as for younger adult
• Exception is routine supine and upright carotid
  sinus massage
• Repeated morning measurements are recommended to
  determine if orthostatic hypotension exists
• 24-hr ambulatory BP may be helpful if meals or
  medications are suspected
• If symptoms continue, or gt 1 cause is suspected,
  further evaluation is indicated

22
Syncope in the Older AdultEvaluation of the
Frail and Elderly

• The rigour of assessment should depend on
  compliance with tests and on prognosis
• For patients who have difficulty standing
  unaided, head-up tilt can be used to assess
  orthostatic changes
• Clinical decisions regarding the value of a
  syncope evaluation should be made for each
  patient based on the benefits to the individual

23
Syncope in the Older AdultConclusions

• Class I Recommendations
• Morning orthostatic blood pressure measurements
  and supine and upright carotid massage are
  integral to the initial evaluation unless
  contraindicated.
• The evaluation of mobile, independent,
  cognitively normal older adults is as for younger
  individuals.
• In frailer older adults, evaluation should be
  modified according to prognosis.

24
CASE 3

• 74 yr old lady
• 3 blackouts, always in church!
• 24 hr ECG normal.
• No postural BP deficit.
• Subjected to tilting Jan 2002.
• CSM supine - NAD.
• 30 min hut did not produce any change in HR or
  BP.
• CSM at the end of tilting time produced 4.2 SEC
  pause
• Also hypotension bp decreased from 137/78 to
  88/59.
• Patient had syncope!

25
(No Transcript)
26
CASE 2

• Mrs IT, 69 yr lady with recurrent blackouts.
• Seen by ENT ?right hearing loss ?Cause
• Seen by neurologist ?cerebrovascular disease. MRI
  brain confirmed deep white matter lesions /small
  vessel ischaemia.
• Still continuing to have black outs
• 24 hour ECG normal.
• Subjected to tilt table test in nov 2001
• Carotid sinus massage nad
• 18 minutes into tilting heart rate dropped to
  48/min, BP dropped to 76/34 and patient lost
  consciousness.
• Recovered on assuming supine position.
• ?Neurocardiogenic syncope.

27

• Commonest cause of syncope in all age groups.
• Underdiagnosed problem.
• Characterised by bradycardia, hypotension or both
  during symptoms.
• In normal individuals- upright position increases
  venous pooling, this leads to increase in heart
  rate and compensatory vasoconstriction.
  Underfilled ventricle then contracts vigorously
  and thus activates the afferent mechanoreceptors.
• In patients with NCS- this rapid increase in
  afferent neural activity produces a centrally
  mediated paradoxical decrease in heart rate and
  peripheral vasodilatation leading to hypotension.
• Tilt table testing is the investigation of choice.

28
TREATMENT

• Medical management-
• Beta blockers- supresses response to circulating
  catecholamines
• Theophyllines- as above.
• Fludrocortisone- volume expansion
• SSRI- central acting- modifies the baroreceptor
  response.
• Midodrine- a specific adrenergic receptor agonist
  with low side effect profile. It binds to
  peripheral receptors and increases vascular tone.
• Pacemakers-for patients with predominant
  cardioinhibition.