Cant feel. Intracardiac tumors are within the heart and therefore can not be felt. Usually no symptoms are present. Some can dislodge and present with stroke like results. Others can obstruct flow across valves and cause heart failure like symptoms when large enough.
Usually, nothing. Most cardiac tumors cannot be felt, but rather are diagnosed on imaging study only. Sometimes, if the tumor is large enough and compressing or irritating cardiac tissue, it may cause palpitations or shortness of breath. Very rarely a large tumor may cause chest pain, but again, this is extremely rare.