Updated: Apr 30, 2019
Heart is the vital organ necessary for pumping blood to every organ in the human body. This organ however has to get nutrition and oxygenation for its normal function through blood vessels called Coronary arteries, the patency of which is most vital at all times. These vessels are lying outer to heart itself and originate from it's main outlet vessel, called Aorta.
Coronary vessels can get clogged by certain disease process called atherosclerosis resulting in Coronary Artery disease. Heart Attack is basically the result of the heart muscle (Myocardium) getting deprived of blood supply with the end result being damaged heart muscle.


To explain this, one should understand that blockage in coronaries is a slow process of developing an Atheroma in the vessel walls. This process continues for years, before it starts to obstruct blood flow in the Coronaries.

When it results in significant block, symptoms set in such as chest pain. Less severe blocks may initiate chest pain during heavy exertions, such as on climbing stairs, rushing for prayer or joining a game etc
Classically the pain of coronary block called Angina appears as dull, constricting ache over the center of the chest that may radiate to the left (rarely the right) inner arm or to the gullet of the neck or the beard area or the middle of the back (also known as the interscapular area). Mild shortness of breath may be seen.
Never neglect any atypical pain that comes on exertion. If angina is suspected, the doctors follow it with a stress test (TMT) to make certain a diagnosis of Coronary Block, then the next step is to look for the location and extent of block, which may be mild or serious, in one vessel or multiple vessels, or in distal segment of the artery or (in the most dreaded) left main artery (this may cause Sudden death).
How can you know these valuable details and the location of the block?
The Gold Standard Test to detect blocks is by Coronary Angiography, done in a Cath lab. Treatment can then be planned, which may be Medical, or by Angioplasty or Surgery. Don't opt for unnecessary investigations like X-Ray, Thallium scan, CT Scan, MRI etc, as these are time delays for definitive treatments.
Angiography and Angioplasty differs, the former being a diagnostic procedure while the latter is a therapeutic modality. Coronary Angiography (Angiogram) is a real time X-ray imaging of dye replacing the blood in each of the coronaries, thus visualizing flow through it's lumen thereby detecting constrictions.
The video below demonstrates Angiography and Angioplasty done successively in the same sitting. A considerable block in a branch of the left coronary artery was detected on Angiogram. This block was then released by Angioplasty using a stent. A free flow is then established in the artery.