Cutting through the rhetoric, it simply means there is an impairment (hypokinesis) of heart wall movement. The impaired movement reduces the heart's ability to pump blood into circulation and lowers EF. Akinesis is cell necrosis (dead), and you are not there, but the condition should treated.
Hypokinesis can be the result of ischemia (reduced blood flow) to the area of impairment. I had the same problem 5 years ago, and with treatment by oxygenating the area, the impairment can be reduced or completely resolved.
Treatment would be a stent or medication. Currently, my EF is in the normal range (55-75%)...represents the percentage of blood pumped with each stroke and no hypokinesis.
Your valves are all in good shape which is a significant positive. On the negative side your heart's pumping function is somewhat weak - ejection fraction refers to the amount of blood your left ventricle (the main pumping chamber) pumps out with each heartbeat. Your heart is pumping out 41-45% of the blood in your left ventricle with each beat. The "normal" reference range for ejection fraction is 55-70% at most hospitals (though I've seen ranges as wide as 50-75%). Your ejection fraction rate is in the "impaired" category and the term hypokinesis essentially reflects the fact that your heart muscle's pumping action is sub-optimal. An ejection fraction of 35% and below is often considered a cut-off where where more aggressive treatment comes into play. You can see that you're in between - you're not in the highest risk category but you're also not in the "normal" category.
The question at hand is what is causing your chest pain and, specifically, what is the cause of your reduced heart function. Assuming your heart is the culprit, I think Encephalomalcia pointed you in the right direction by asking about coronary disease - your angiogram almost certainly included a contrast dye release to investigate your arteries for blockages. Other common potential causes of a weak heart include valvular disease (we know your valves are good), hypertension (do you have high blood pressure?) which can lead to an enlarged heart that may not pump as effectively (often is at least partially reversible with treatment) and scarring due to prior heart attacks/viral illnesses (though much of the heart attack category would be covered by coronary disease which your angiogram should have investigated). One big step towards answering these questions would be to consider other information about your heart which wuld have been collected during the angiogram or during an echocardiogram (have you had that test? Its a sonogram of the heart). The echo in particular would detail the thickness of your heart walls and the size of the chambers of your heart (you have 4 heart chambers and changes in their structure, size and function can point to the underlying cause of heart troubles).
I would encourage you to get copies of any other tests done and engage your Dr. with your concerns. Western medicine has made some huge strides regarding heart health and recovery and people with heart function much worse than yours often improve and live comfortably for many, many years (you can find some of those very people on these boards!) Last note - there are several measures of heart health beyond ejection fraction and a thorough work up will include a consideration of those factors as well. Best of luck.
You Hypokinesis could be coming from coronary artery disease. Had you had tests for blockage in your arteries? Chest pain sound suspicious for blockage. Have you had a stress test lately?