The septum (wall separating left and right heart chambers) is normal size and flexibility, but there is an area of the septum that is unresoved whether or not there is ischemia (lack of blood flow usually due to blocked (occluded) vessels).
Whether there are serious issues depends on your symptoms, medical history and any other signs that may support a medical problem. The fact your septum is of normal size and no wall impairment indicates there are no serious consequences from ischemia or a prior heart attack.
Because the septum supports and provides a pathway for electrical impulses for the heartbeat contractions, any medical impairment to that area can cause arrhythmia (irregular heartbeats).