• I see a lot of patients who are sent to me for evaluation of dizziness.  On the surface you wouldn’t think a cardiologist would have much to do with a symptom that relates more to the head than the heart, but there is some logic to it—poor blood flow to the brain could lead to dizziness and, since blood flow starts in the heart that could be the place to look. While it is true that diminished (or occasional absence of) blood flow from the heart can render a person devoid of the faculties that allow for stable upright posture, true dizziness is rarely the result of impairment of the cardiovascular system.
• Lightheadedness. If you want to experience lightheadedness, here are some things you can try. First, crouch down near the floor and stay there for about a minute. Now, abruptly jump back to the upright position. In many people this will produce a sensation of “graying out.” The sensation of lightheadedness you have relates to something called orthostatic or postural hypotension. In people (particularly people with longstanding diabetes) this can be debilitating, but in others it’s mild and quite natural. A sudden but temporary lightheadedness in this scenario can indeed be a marker for some type of transient cardiac disorder, such as a rhythm disturbance, and your best bet is to start by testing the heart. This type of lightheadedness would probably be most correctly classified as pre-syncope, a term that implies the condition of near-fainting.
• Disequilibrium. Let’s say you’re walking down your hallway at home and you start to get the perception that you’re tipping to one side. You stagger to right yourself, but even when you’re ramrod straight and steadied against the wall you can’t escape the feeling that the world is off-kilter. Possible sources of the problem include impairment of the cerebellum of the brain (stroke, tumor), impingement of spinal cord nerves (cervical spondylosis), and generalized neurological disorders such as Parkinson’s disease.
• Vertigo. The inner ear has an intricate mechanism, called the vestibular system, of keeping track of the movement of your head. The most common cause of this impairment is benign positional vertigo (BPV), a disorder that comes as a result of calcium debris building up in the posterior semicircular canal and typically manifests itself as a brief, sometimes intense, spinning sensation that accompanies rapid movements of the head. Laying one’s head down on the pillow of the bed seems to be a common inciting event.
• In one published study that tallied the various causes of dizziness in a primary care clinic, the breakdown was as follows: BPV 54%; lightheadedness (presyncope) 6%; disequilibrium 2%; and psychiatric 16%. It was multifactorial in 13% and unknown in 8%.

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