Probably the most important way to improve the long-term outcome for patients with coronary disease is prevention. This includes quitting smoking, taking up a healthy diet and regular exercise. Patients with high blood pressure and cholesterol, and diabetes also need to be identified and treated — the use of aspirin and statins (to reduce cholesterol) have been shown to improve the outcome of patients with coronary disease and to reduce the risk of a heart attack
Drug treatments for angina work in two main ways — either by reducing the amount of oxygen needed by the heart muscle (beta-blockers), or by increasing blood flow to the heart (nitrates and calcium channel blockers). Aspirin should be taken by everyone with angina because it works by thinning the blood which then clots less easily; aspirin has been shown to reduce the risk of heart attack by 25 per cent in people with coronary artery disease.
Treatment of a heart attack requires urgent reopening of the blocked artery, to restore the normal blood supply to minimise death of the heart muscle. This can be achieved by clot dissolving drugs (thrombolytic therapy) and/or emergency coronary angioplasty which is increasingly recognised as the gold standard for treatment.

Coronary Angiography (cardiac catheter)

When angina occurs despite drug treatment or when there are features which suggest that the narrowings in the coronary arteries may determine a patients life span coronary angiography is recommended..
Following local anaesthetic a long, flexible, hollow plastic tube (a catheter) is inserted into an artery in the groin. Using X-ray imaging the catheter is steered through the blood vessels and into the coronary arteries at the start of the aorta (main blood vessel from the heart to the body). A special dye (contrast liquid) which is injected into the tube shows up under X-ray to reveal if the coronary arteries are narrowed or blocked. The procedure has some RISKS but seeing the extent and position of the narrowings in the coronary arteries allows a cardiologist to determine the best method of treating angina.

Coronary Angioplasty/stenting Blood flow to the cardiac muscle can be improved by making the blood vessels wider. During angioplasty/stenting (also called PCI - percutaneous coronary intervention) a balloon-tipped catheter is threaded over a guide wire until it reaches the narrowed area (as identified in an angiogram ). When in position, the balloon is inflated at high pressure, compressing the obstructing atheromatous plaque and enlarging the inner diameter of blood vessels so that blood flows more readily. This procedure is known as balloon angioplasty
Angioplasty was introduced in 1979 but "elastic recoil", where arteries return to their original size following removal of the balloon and “restenosis” the development of scar tissue at the site of balloon inflation were responsible for re-narrowing of the vessel in 20 – 50% of patients.

 "Stents" were incorporated to prevent elastic recoil and to reduce the chances of the coronary artery occluding soon after balloon inflation. The stent (a tiny cage of surgical grade stainless steel) surrounds the outside of the balloon and as the balloon is inflated the stent expands and locks into place to form a scaffold, holding the artery open once the balloon has been removed. All interventional procedures have an element of risk but the chances of a successful outcome in a non emergency situation are >98%.
Inevitably some injury occurs to the artery occurs during stent placement. This can trigger a healing process where scar tissue collects on the inside of the stent, making the stented vessel narrow again. It is most likely to occur in small vessels long stents and in people with diabetes.

Stent being deployed