Cardiac Investigation
Tilt Table Test — Investigating Blackouts
The head-up tilt table test is the definitive investigation for unexplained syncope, pre-syncope, and postural symptoms. By safely reproducing the conditions that trigger a blackout, it identifies the mechanism responsible — and points directly to the right treatment.
The Test
Reproducing a Faint in a Safe, Controlled Setting
Syncope and blackouts are by definition intermittent — they happen unpredictably and are over in seconds. Standard tests such as a resting ECG or an echocardiogram record the heart at rest, not at the moment of collapse. The tilt table test bridges this gap by recreating the physiological conditions that provoke syncope while continuous monitoring captures exactly what happens to the heart rate and blood pressure as symptoms develop.
The test is performed on a motorised table that tilts from horizontal to a 60–80° head-up position. Gravity shifts blood towards the legs, reducing venous return to the heart — the same mechanism that triggers vasovagal faints when standing in queues or in hot environments. A normal cardiovascular system compensates automatically. In patients with vasovagal syncope or orthostatic hypotension, this compensation fails, and blood pressure or heart rate drops — reproducing their symptoms under careful medical supervision.
The test is entirely safe. The room is staffed throughout, the table returns to horizontal within seconds of any significant response, and full recovery is rapid. The information gained — the precise type of response, the timing, and the degree of heart rate and blood pressure change — directly informs whether a pacemaker, medication, or lifestyle programme is the right treatment.
Who Should Have This Test
When Dr Nijjer Recommends a Tilt Table Test
The tilt table test is not a first-line investigation for every faint. It is selected when the clinical picture points to reflex or autonomic syncope, or when the cause of blackouts remains uncertain after initial cardiac tests.
- Unexplained syncope — recurrent blackouts where cardiac arrhythmia has been excluded but no definitive diagnosis has been reached
- Recurrent pre-syncope — frequent near-blackouts, lightheadedness, or near-falls that have not been captured on ambulatory monitoring
- Suspected vasovagal syncope — to confirm the diagnosis and characterise whether the heart slows (cardioinhibitory) or blood pressure drops (vasodepressor) — critical for treatment selection
- Suspected POTS — Postural Orthostatic Tachycardia Syndrome, particularly in younger patients with chronic fatigue, palpitations on standing, and lightheadedness
- Orthostatic hypotension — when lying/standing blood pressure measurements are inconclusive but symptoms are strongly postural
- Syncope with pacemaker consideration — to document asystole or severe cardioinhibition before implanting a pacemaker
- Falls in older patients — when an autonomic or reflex mechanism is suspected as the cause of unexplained falls
Not Suitable If…
The tilt table test is generally very safe, but Dr Nijjer will review your history and medications before proceeding. It may not be appropriate in the following circumstances:
- Significant aortic stenosis or outflow tract obstruction — provoking hypotension could be hazardous
- Haemodynamically significant coronary artery disease — sustained hypotension should be avoided
- Recent stroke, TIA, or severe carotid disease
- Severe uncontrolled hypertension
- Pregnancy
In most patients with suspected vasovagal syncope, the test carries negligible risk beyond transient symptoms.
Unexplained Syncope
Vasovagal Diagnosis
POTS Assessment
Orthostatic Hypotension
Pre-Pacemaker Evaluation
Recurrent Falls
Unexplained Near-Falls
Step by Step
What Happens During the Test
The full appointment takes two to three hours. The active testing period is typically 45–90 minutes. You will be accompanied throughout by a cardiac physiologist and supervised by Dr Nijjer.
1
Preparation & Monitoring Set-Up
ECG electrodes are applied to your chest, and a continuous non-invasive blood pressure cuff is fitted to your finger or arm — recording beat-to-beat blood pressure in real time. A cannula may be placed in your arm in case pharmacological provocation is needed.
10–15 minutes2
Baseline Flat Phase
You lie flat and completely still while baseline blood pressure and heart rate recordings are established. This determines your resting cardiovascular parameters and confirms the monitoring system is working accurately before the tilt begins.
10–20 minutes3
Passive Upright Tilt
The table tilts smoothly to 60–80° head-up. You are secured safely with straps. Blood pressure and heart rate are monitored continuously. You are asked to remain still and report any symptoms as they develop — dizziness, nausea, visual changes, or chest tightness.
Up to 40 minutes4
Provocation Phase (if needed)
If no response occurs during passive tilting, a small dose of sublingual glyceryl trinitrate (GTN spray) or an intravenous agent is given to sensitise the vasovagal reflex. The test then continues for a further 15–20 minutes. Not all patients require this phase.
15–20 additional minutes5
Positive Response & Recovery
If a vasovagal or hypotensive response is triggered, the table returns to flat immediately and your symptoms resolve within seconds to a few minutes. You are observed throughout. The response is fully recorded and will be reviewed in detail with you.
Minutes to recover6
Results & Discussion
Dr Nijjer discusses the findings with you the same day. A full written report is produced. If a positive result is obtained, a treatment plan is agreed before you leave. If the test is negative, next steps — such as a loop recorder implant — are discussed.
Same dayInterpreting Your Result
What Each Response Pattern Means
The type of positive response guides treatment. A cardioinhibitory response (heart slows dramatically) may indicate a pacemaker is appropriate; a vasodepressor response (blood pressure drops alone) is managed differently. A negative test is also informative.
Normal Result
No Response to Tilt
Blood pressure and heart rate remain stable throughout the test. No syncope or pre-syncope is provoked. This does not mean your symptoms are not real — it means vasovagal or orthostatic mechanisms have not been captured in this test session.
May indicate arrhythmia as cause — loop recorder implant often recommended next
Vasovagal — Mixed (Type 1)
Blood Pressure & Heart Rate Both Fall
The most common positive pattern. Both blood pressure and heart rate drop simultaneously — confirming vasovagal syncope. Heart rate falls by ≥10% but does not go below 40 bpm. Symptoms typically precede consciousness loss by several seconds.
Managed with lifestyle measures, counter-pressure manoeuvres, and occasionally medication
Cardioinhibitory (Type 2B)
Heart Pauses — Asystole Recorded
The heart rate falls abruptly to very low levels or stops entirely for more than three seconds. This is the most dramatic — and clinically significant — positive response. Loss of consciousness occurs rapidly, often without warning.
Strong indication for pacemaker implantation to prevent future collapse
Vasodepressor
Blood Pressure Falls, Heart Rate Maintained
Blood pressure drops significantly while heart rate does not slow. The drop in blood pressure alone is sufficient to cause loss of consciousness. A pacemaker would not prevent this — the problem is the blood pressure, not the heart rate.
Managed with medications, volume expansion, and postural lifestyle advice
POTS
Heart Rate Rises Excessively on Standing
Heart rate increases by ≥30 beats per minute (or ≥40 bpm in those under 19) within ten minutes of tilting, without a significant drop in blood pressure. Patients typically experience palpitations, breathlessness, and lightheadedness on standing rather than true blackout.
Managed with hydration, salt loading, graded exercise, compression, and targeted medications
Orthostatic Hypotension
Blood Pressure Drops Within 3 Minutes of Tilting
Systolic blood pressure falls by ≥20 mmHg (or diastolic by ≥10 mmHg) within three minutes of head-up tilting, confirming orthostatic hypotension. Common in older patients, those on multiple blood pressure medications, or those with autonomic neuropathy.
Medication review, postural advice, compression garments, and fluid management
Preparing for Your Appointment
What to Do Before the Test
Minimal preparation is required. The most important things to organise in advance are listed below. You will receive written instructions from Dr Nijjer's secretary when your appointment is booked.
- Fast for 2–4 hours beforehand — a light meal is permissible earlier in the day, but avoid eating immediately before the test. A full stomach can trigger nausea during the tilt phase.
- Continue your regular medications unless Dr Nijjer specifically advises you to withhold them. Some medications (midodrine, fludrocortisone, beta-blockers) may be paused to improve test sensitivity — you will be advised individually.
- Stay well hydrated — drink plenty of water the day before and morning of the test. Dehydration lowers blood pressure and may increase the risk of an early response before adequate monitoring data is obtained.
- Wear comfortable, loose clothing — the ECG electrodes and blood pressure monitoring cuff need to be attached to your skin. Avoid tight sleeves or restrictive upper clothing.
- Bring someone to accompany you home — if a positive response is triggered, you may feel tired or unwell for a few hours afterwards. Driving home yourself on the same day is not advised.
- Allow 2–3 hours for the appointment — this includes preparation, the test itself, monitoring during recovery, and a full discussion of results with Dr Nijjer.
- Bring a list of all current medications — including over-the-counter drugs and supplements, so Dr Nijjer can assess any potential effects on the result.
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Ready to Find an Answer?
If you have experienced unexplained blackouts or recurrent near-faints, Dr Nijjer can arrange a full cardiac assessment including a tilt table test. Urgent appointments are available within 48 hours for concerning symptoms.
Call us: 0203 983 8001 · jessica@oneheartclinic.com