I know several people who have had heart attacks. Their first contact with the medical system has been with paramedics -- firemen with training in emergency medical procedures. The next step will usually be an emergency room where the first physician is unlikely to be a cardiologist.
But I was arguing with someone who asserts your problem would cease to exist if you followed his dietary advice. I'm not sure what you are doing in the middle of this.
My cardiologist and most other doctors I have talked to, point at a dietary influence to my condition(I take lipitor and my cholesterol level is 90 - my triglycerides are high). I hate fish. As to what I am doing in this, I merely pointed out that the Dr. who headed the "quackery" site, lost a suit involving a defamation.