Guest post by Francesco Santoni-Rugiu, MD, Director, Outpatient Services, Al-Sabah Arrhythmia Institute at Mount Sinai St. Luke’s
Syncope is a sudden, unexplained loss of consciousness; most commonly referred to as a fainting spell. A syncopal episode implies that the fainting was sudden and there was an immediate return to feeling normal. Patients typically describe the episode by saying “I was fine and then I must have passed out, because I found myself on the floor; I got up and I was ok.” This type of fainting episode is different from one where you get progressively weaker prior to passing out. These episodes are more likely due to intoxication, or low blood sugar. Also, a different type of loss of consciousness is the one associated with seizures, or a concussion when the patient recovers consciousness but does not feel back to normal but rather groggy, confused.
True syncope, the sudden on/off event that we are discussing, is the result of the brain not receiving enough blood flow to maintain consciousness. This leads to the brain temporarily shutting down or “rebooting.”
How is it diagnosed?
It is difficult to determine the cause of syncope, since there are dozens of possibilities and only about 50% of patients are evaluated; however, as with most medical conditions a thorough physical examination and complete medical history are important. During your initial exam it is important to provide your doctor with as accurate a description as possible of how you felt during the moments leading up to and after the episode.
Your physician may want to run some tests including blood tests, an electrocardiogram or EKG, and may ask you to wear a Holter monitor so that they can look for heart rhythm disturbances. Additional tests such as a CT scan or MRI may also be requested.
The results of these tests will help your physician determine if further testing is needed and if the syncope was the result of a cardiovascular (heart) problem.
Is it my heart?
While not all fainting episodes are the result of a heart problem, many are. If syncope is the result of a cardiovascular condition, it is most commonly due to a cardiac arrhythmia (abnormal heart rhythm) which causes a lack of blood flow to the brain.
For example, a sudden pause in the heart contraction due to complete electrical block within the heart (known as complete heart block) or an instantaneous jump in the heart rate such a ventricular tachycardia, a condition whereby the heart starts beating extremely fast from its lower chambers (ventricles).
Additional cardiovascular problems that can cause syncope include but are not limited to tightening of the heart valves (aortic stenosis or mitral stenosis), intermittent thickening of the heart muscle (hypertrophic cardiomyopathy), or blood clots and their complications (pulmonary embolisms and pulmonary hypertension).
How is syncope treated?
There is no designated treatment for syncope; however, depending on the cause there may be ways to prevent additional episodes from occurring. Your physician will work with you to determine the best course of treatment after a specific diagnosis is made.
How serious is syncope?
The severity of the underlying condition determines the seriousness of the syncope. Unfortunately, syncope of cardiac origin can be life threatening; moreover any loss of consciousness may put your life at danger, for instance when you drive or swim.
If you have a history of fainting and would like to get evaluated by a cardiac electrophysiologist, please call the Al-Sabah Arrhythmia Institute at 212-523-2400.