Why does my heart randomly start beating really hard and fast I can see it pounding through my clothes.it causes me quite a bit of pain and can last for hours sometimes it can wake me up in the middle of the night and is hard to sleep because of the pain I don t know what s causing it as it doesn t happen at any particular time I could be sat doing nothing and it will start up
You must be having some arrhythmia. Most likely to be atrial fibrillation but could be any arrhythmia. Please have an ECG and Echo done. If both are normal you may need Holder testing. Based on result you may be suggested some medications or lifestyle modification.