It sounds to me like you are experiencing either PVC's (premature ventricular contractions) which originate in the lower chambers of your heart, or PAC's (premature atrial contractions) which originate in the upper chamber of your heart. With this “extra” beat, a pause usually causes your next normal heartbeat to be more forceful. This is what you are feeling. Almost everyone experiences these "disruptions" from time to time and many people are not even aware they have happened! THE most important thing to remember about these episodes is that in a structurally sound heart, they are totally benign. They are NOT an indication of heart disease or an impending heart attack. Keep in mind that your heart beats, on average, 100,000 time PER DAY! Multiply that number by your age and I think you'll be amazed at what an incredible "machine" our hearts are. As with any machine that depends on an electrical current to keep it running smoothly, there are going to brief moments when there is a slight "blip." A minor interruption of the current which self-corrects and continues to run normally. You said that a few months ago you had a full cardiac workup and your heart was diagnosed as structurally fine, which is the best diagnose we can wish for! During that exam, did you tell the cardiologists about the PVC's or PAC's you were experiencing? Did you mention the cold sweats and the chest pain? If you DID and they said your heart was fine, then your symptoms sent up no red flags for them to do any further testing. They SHOULD, on the other hand, have talked to you in more detail about your symptoms and I'm very surprised they didn't………especially if you told them about your concerns and fears. If these symptoms have appeared SINCE your cardiac workup, my thoughts, and definitely my advice, is to see your cardiologist again and tell them ALL of your symptoms. I am NOT a doctor and most especially I'm NOT a cardiologist, so anything I say about your symptoms is just guessing and when it comes to our hearts, the very LAST thing we want is someone "guessing" about what may be wrong. We want and need to KNOW for certain what, if anything is going on so it can be treated. PLEASE put your mind at peace and see your cardio again. I'm sorry I couldn't give you far more definitive answers, but I think everyone on this forum would agree with me that another visit to your cardiologist is the wisest move. I wish you the best and hope you'll let us know how you're doing.