People commonly experience isolated, premature heart beats that originate outside the normal conduction system of the heart. These may be completely benign. However, in some instances, they can occur so frequently that they pose a problem for your heart. Given that this sensation in your chest is rapidly followed by a feeling of near loss of consciousness, it is critical that you seek consultation with your physician to help determine the cause.
Exercise normally causes an increased heart rate in order for the heart to pump oxygen-rich blood to your muscles. This trigger for an increased pulse can occasionally set off an arrythmia, which is sometimes sensed as an extra heart beat. Common arrhythmias include atrial fibrillation, atrial flutter, atrioventricular reciprocating tachycardia, AV nodal reentrant tachycardia, or atrial tachycardia. More uncommonly, the arrhythmia could originate in the ventricles, or bottom chambers of your heart, such as with ventricular tachycardia. Given your symptoms, it is important for you to be evaluated by your physician. A typical evaluation consists of a thorough history and physical exam and EKG. Depending on these findings, it is possible you would need to also undergo an ultrasound
of your heart (transthoracic echocardiogram
), treadmill exercise test, or 24-hour EKG monitor.
Your symptoms of almost fainting
are commonly called pre-syncope. In addition to the cardiac causes already mentioned, other potential causes include vasovagal syncope, orthostatic hypotension, cardiac valvular disease, hypertrophic obstructive cardiomyopathy, or other diseases of your heart or brain. It is imperative that you seek consultation with your physician to help determine if any of these may be at play.