Dizziness and vertigo are common symptoms that involve a disturbance in your sense of orientation, but they describe different sensations. Dizziness is a general term for feeling faint, light-headed, or unsteady, often described as presyncope. Vertigo is the specific illusion of movement, where you or your surroundings feel like they are spinning or swaying. Cardiovascular health directly controls the flow of blood to the brain and inner ear. Any condition that compromises the heart’s ability to pump blood efficiently can manifest as a problem with balance.
The Vestibular System and Circulatory Needs
The body’s complex balance system relies on continuous, steady delivery of oxygen and nutrients. This system includes the inner ear’s vestibular apparatus and the balance centers located in the brainstem and cerebellum. Blood flow to the inner ear is supplied by the labyrinthine artery, which is typically a branch of the basilar artery.
Unlike the brain, which possesses robust mechanisms for regulating its own blood supply, the delicate blood vessels of the inner ear are less protected from changes in systemic blood pressure. A drop in overall arterial blood pressure leads to a proportional decrease in blood flow to the cochlea and vestibular organs. Even a temporary drop in cardiac output can quickly disrupt the inner ear’s function. Reduced circulation causes a temporary shortage of oxygen to the sensory hair cells, which can trigger abnormal electrical signals that the brain interprets as spinning or unsteadiness.
Vertigo Stemming from Cardiac Output and Pressure Issues
The most frequent cardiac causes of dizziness are those that directly impair the heart’s pumping efficiency or the overall pressure within the circulatory system. When the heart cannot move enough blood per minute, the condition is known as low cardiac output. This reduced flow leads to a state of global cerebral hypoperfusion, which is a temporary lack of blood supply to the entire brain.
Arrhythmias, or irregular heart rhythms, are a prime example, as they critically affect output. A heart beating too slowly (severe bradycardia) or too rapidly (tachycardia, such as atrial flutter) prevents the ventricles from filling or emptying correctly, causing a sharp drop in the volume of blood pushed into circulation. This sudden, inefficient pumping results in a temporary decrease in blood pressure, leading to light-headedness or true vertigo.
Another common hemodynamic cause is severe hypotension, or abnormally low blood pressure. Orthostatic hypotension is a specific type where blood pressure drops significantly upon standing up from a sitting or lying position. This occurs because the cardiovascular system fails to constrict blood vessels quickly enough to compensate for gravity pooling blood in the lower extremities. Heart failure, particularly with a reduced ejection fraction, also causes chronic low cardiac output because the damaged muscle cannot contract with enough force to meet the body’s demands.
Vertigo Caused by Embolic Events
Vertigo can also be a sign of a blockage event originating in the heart that travels to the brain’s balance centers. This mechanism involves an embolism, which is a clot or piece of plaque that breaks loose from the heart or a major artery. Atrial Fibrillation (AFib) is a leading cardiac source of these clots because the chaotic, uncoordinated beating of the atria allows blood to pool and clot, typically in the left atrial appendage.
If one of these clots travels into the systemic circulation, it can cause a stroke or a Transient Ischemic Attack (TIA). Vertigo that is sudden and severe is a hallmark symptom when the clot lodges in the posterior circulation, which includes the vertebral and basilar arteries supplying the brainstem and cerebellum. This area contains the central processing centers for balance information received from the inner ear.
Ischemia, or a lack of oxygenated blood, in the cerebellum or brainstem can cause acute vertigo that is distinct from peripheral inner ear conditions. A TIA in the vertebrobasilar territory may produce intense spinning, unsteadiness, and nausea, sometimes without the typical weakness or slurred speech associated with an anterior circulation stroke. The presence of these symptoms requires immediate investigation, as they indicate a serious vascular event caused by an obstruction originating from the heart.
Recognizing When Dizziness Signals a Heart Emergency
While many instances of mild dizziness are benign, the symptom can be the first or only warning sign of an acute cardiovascular event. It is important for individuals to recognize accompanying “red flag” symptoms that suggest the dizziness is related to a life-threatening heart problem.
Dizziness or vertigo accompanied by chest pain, which may feel like pressure or squeezing, warrants immediate emergency attention. Shortness of breath, especially when not exerting yourself, along with sudden, severe light-headedness, should also be treated as a medical emergency.
Fainting, or syncope, which is a transient loss of consciousness, is a strong indicator of critically low blood flow to the brain, frequently caused by a severe arrhythmia. Other concerning signs include a pounding heart or sudden, irregular palpitations, which suggest the heart rhythm is dangerously unstable. Any combination of dizziness with severe headache, numbness, weakness on one side of the body, or difficulty walking or speaking indicates a possible stroke or TIA and requires urgent medical evaluation.