I have read all of this thread, most of the people have responded in relation to coronry heart disease.
I have dilated cardiomyopathy, which means that my heart is enlarged and the heart muscle is not as strong as it should be, it becomes slack, like untoned muscle, this was caused by a virus when I was 16,(1981) the loss of muscle strength meant that the heart could not push all the blood out of the chambers and resulted in the blood clotting, causing a cerebral embolism and paralyis of the left hand side, due to the blood clot sticking in the brain, this was broken down by using Warfain (anti-coagulant) 1981. It also damaged the electrical pathway, causing a complete heart block, my heart could only beat at 44bpm, I now have no underlying heart rate, this condition is progressive and is only one example of cardiomyopathy, there are lots of different types.
I would advise that you contact the cardiomyopathy Association, they have a website and you can call them and speak to people with medical knowledge, )Heart Failure Nurses). The British Heart Founation also have expert teams that you can talk to, as advised, keep a diary and as much detail as you can to assist with diagnoses.
Don't give up as I know people that have had symptoms and been going to the GP repeatedly and not been diagnosed, as the GP's are not aware of all heart conditions, speak to some of the experts in the field, BHF & CMA explain your symptoms, if nothing else it will put your mind at rest and if they think you may have an undignosed condition can advise you on how to deal with your GP and what he should be looking for.
As mentioned by previous people anxiety, panic attacks and lots of conditons can cause similiar symptoms, you need to listen to your body, pain, , not feeling like doing anything are classic symptoms.
Although i was diagnosed at 16, I had GP's that thought it was despression, even though I didn't feel depressed, had fluid retention, muscular pains etc, I was under a heart consultant, but not heart failure specialist, no one picked up it was the condtion that had progressed.
Heart problems are split into different catergories, Cardiomyopathy, covers it in a broad spectrum, eg, dilated, Hypertrophic, Arrythmia (electrical problems, and many others, some are hereditary, some caused by viruses, there are also congentital conditions. I am an outpatient at Papworth Hospital under the Transplant Team to help me manage the condition, they split heart disease into key areas, plumbling, eg, valves, arteries, veins, electical and muscular problems.
You could also have a holter test which is a portable ecg monitoring system, you are wired up for 24/48 hours , the tape is diagnosed for any abnormalities. I also had sharp pains in my chest, prior to being diagnosed, I would pursue this with your GP, chest xrays, blood tests, can show some abnormalities, but not all heart conditions.
Good Luck
Nikki