| Palpitations are defined as an "abnormal awareness of heartbeat", if you have pauses in heart rhythm, extra beats, or abnormal rhythms you can get a thumping, squirming, or fluttering feeling in your chest. It can feel quite dramatic and can be associated with feeling short of breath. An involuntary diaphragm contraction would produce a sharp breath in, superimposed on your normal breathing ( a hiccup is a brief diaphragm contraction).
Hope that helps!
Neil |