Fainting and dizziness: when the heart may be involved

Understanding fainting and dizziness

A faint (the medical term is syncope) is a brief, complete loss of consciousness caused by a temporary drop in blood flow to the brain, with a full recovery on its own. Dizziness and light-headedness are milder cousins of the same problem — a sense that a faint might be about to happen, without actually losing consciousness.

The brain depends on a continuous supply of oxygen-rich blood, delivered at an adequate pressure. Anything that briefly interrupts that supply — blood pressure dropping too low, the heart beating too fast, too slow or too irregularly to pump effectively, or the blood vessels in the legs failing to keep blood moving back up to the heart against gravity — can cause a faint. Most faints are the body's normal reflexes overshooting, for example when standing suddenly or during a strong emotional response. A minority come from the heart's rhythm or pumping ability, and these need a more careful look because the same mechanism that can cause a brief faint can, in rare cases, be dangerous.

What fainting and dizziness feel like

People experience these episodes differently. These are useful clues to discuss with a clinician, not a checklist for diagnosing yourself.

• ●A blackout, collapse or unexplained fall, sometimes with no memory of the moments before
• ●Light-headedness or a swimming sensation, especially when standing up quickly
• ●Warning signs before an episode — nausea, sweating, ringing in the ears, tunnel vision or feeling suddenly hot
• ●Palpitations, a racing or pounding heartbeat, just before losing consciousness
• ●Confusion, weakness or injury noticed after coming round
• ●Episodes brought on by a specific trigger — standing for long periods, heat, pain, the sight of blood, or straining

How long an episode lasts, what you were doing beforehand, and what a witness observed — including any jerking movements, which point away from a simple faint — are all valuable details for your clinician.

What causes fainting and dizziness

Grouping the causes this way can help you see where your own experience might fit.

Reflex (vasovagal) faints

The most common cause overall. A normal nervous-system reflex overreacts to a trigger — standing for a long time, heat, pain, fear, or the sight of blood — causing blood vessels to widen and the heart rate to slow suddenly. Blood pressure drops briefly, the brain is under-supplied for a moment, and consciousness is lost, usually with some warning beforehand.

A drop in blood pressure on standing

Called orthostatic hypotension — blood pressure falls when moving from lying or sitting to standing, because the circulation is slow to adjust. It is more common with dehydration, certain blood pressure medicines, and in older adults.

Heart rhythm problems (arrhythmias)

A heartbeat that is too fast, too slow, or too irregular can pump blood less effectively, briefly reducing supply to the brain. This group needs careful evaluation because some rhythm problems are serious.

Structural heart problems

A narrowed heart valve or a weakened heart muscle can limit how much blood reaches the brain during exertion, particularly causing fainting during activity.

Causes outside the heart

• ●Low blood sugar, which triggers sweating, shakiness and light-headedness
• ●Anaemia (a low blood count) — common in Nigeria, it reduces the oxygen reaching the brain
• ●Dehydration, particularly in Abuja's heat, reducing the blood volume available to maintain pressure
• ●Seizures, which can resemble fainting but usually involve jerking movements and a longer recovery
• ●Anxiety and panic, or rapid, deep breathing that lowers blood carbon dioxide levels

Who is more likely to faint

• ●Older age
• ●Known heart disease, including a previous heart attack or valve problem
• ●High blood pressure medicines, particularly when several are combined
• ●Diabetes, which can affect the nerves controlling blood pressure regulation
• ●Anaemia
• ●Dehydration or prolonged standing in hot conditions
• ●A family history of unexplained fainting or sudden cardiac events

What happens if a serious cause is missed

Most faints are benign and carry little risk beyond the fall itself. The minority caused by a heart problem matter more, and are why new fainting is always worth assessing rather than dismissing.

Injury. Falls during a faint can cause fractures, head injury, or harm while driving or working at height — often the most immediate real-world risk.

Recurrent episodes. An unaddressed cause tends to recur, affecting confidence, independence and safety at work.

Cardiac causes left untreated. Rarely, a serious rhythm or structural heart problem behind fainting can progress to more dangerous events if not identified and treated.

How Cardiocare finds the cause

The right pathway depends on your symptoms, examination and overall health. It typically draws on some or all of the following:

• 01
  Event history. A detailed account from you and, where possible, any witness — what happened before, during and after the episode.
• 02
  Blood pressure lying and standing. Checks whether blood pressure drops abnormally on standing.
• 03
  ECG (electrocardiogram). A painless recording of the heart's electrical activity, taking minutes.
• 04
  Holter or event monitoring. A portable ECG recorder worn for a day or longer to catch a rhythm problem if it recurs.
• 05
  Echocardiogram. A painless ultrasound scan of the heart's structure and pumping.
• 06
  Blood tests. Full blood count for anaemia, blood sugar, and electrolytes.
• 07
  Tilt-table testing. For selected cases, blood pressure and heart rate are monitored while the body position is gradually changed, to reproduce and study the trigger.
• 08
  Neurological assessment. Where the history suggests a seizure or other neurological cause rather than a faint.

How fainting and dizziness are treated

Treatment is matched to the cause identified — there is no single treatment for fainting as such.

Reflex faints

Often managed with reassurance, avoiding known triggers, keeping well hydrated, and learning to recognise and act on early warning signs by sitting or lying down promptly.

Blood pressure drops on standing

May involve adjusting medicines that lower blood pressure, increasing fluid and salt intake as advised, and standing up in stages.

Medicines, by class

Where a rhythm or blood pressure cause is confirmed, your clinician will discuss the right option for you:

• ●Beta blockers — used for selected rhythm-related causes
• ●Adjustment of existing blood pressure medicines — where they are contributing to drops on standing

Procedures

Available through Cardiocare's on-site cardiac catheterisation laboratory for selected patients:

• ●Pacemaker implantation — for a heart rhythm that is too slow
• ●Catheter ablation — for selected fast rhythm problems causing fainting

Living with fainting and dizziness: everyday self-care

• ✓Stay well hydrated, especially in Abuja's heat, unless your clinician has advised otherwise for a specific condition
• ✓Rise slowly from lying or sitting, pausing before standing fully
• ✓Recognise your own warning signs and sit or lie down immediately when they start
• ✓Avoid prolonged standing where possible, especially in heat or crowds
• ✓Do not drive until recurrent unexplained episodes have been assessed
• ✓Keep a simple diary of episodes — time, trigger, warning signs and duration — for your appointments

Preparing for your appointment

What to bring

• ✓A witness account of the episode, if anyone saw it happen
• ✓A list of all medicines you take, including herbal and over-the-counter preparations
• ✓Any previous ECGs, blood test results or hospital letters
• ✓Your HMO card and a valid means of identification

What we will ask

What you were doing beforehand, any warning symptoms, how long the episode lasted, how you felt afterward, and whether anyone witnessed it.

Questions worth asking us

• ●What do you think caused this episode?
• ●Do I need any tests, and what will each involve?
• ●Is it safe for me to drive or work at height?
• ●What should I do if it happens again before my next visit?