ANGINA

In medical terms chest pain related to heart disease is called Angina. It means chest pain due to decreased blood supply to the heart muscle and it is usually termed as coronary heart disease which implies that the origin of the disease is from one of the coronary artery(artery supplying the myocardium) supplying the heart and the most common reason is Atherosclerosis (deposition of cholesterol on the walls of artery).

Chest pain is the one and most common complaint made by a patient with coronary heart disease.

When a patient comes under a condition of chest pain, it is a doctor’s responsibility to differentiate the chest pain and the plausible cause of it. Chest pain caused by interruption in the blood supply of myocardium usually results in a unique way of presentation with pain radiating to the arms, jaw, shoulder and back.

We always have a wrong approach when it comes to chest pain. We think that it is heart attack when a person has a chest pain. It is not the situation. Chest pain has various other roots. Especially heart attack should be differentiated from similar forms of disease such as stable and unstable angina.

These ischemic changes occur when there is imbalance between oxygen supply to the cardiac muscle and oxygen demand by the cardiac muscle. We must understand the mechanism that our heart cells needs oxygen to perform its normal function i.e. to pump the blood out of the heart chambers into the aorta(blood vessel). The main function of a blood vessel is to supply oxygen to a particular area. So when a coronary blood vessel is narrowed due to atherosclerosis, then there is decreased blood supply which in turn results in decreased oxygen supply. So during physical or emotional stress, heart needs more oxygen to compensate the heavy work of the myocardium. But in these cases there is decreased oxygen supply resulting in pain and irreversible necrosis of the myocardium.
We differentiate the clinical manifestation of coronary heart disease into Acute and Chronic.
Acute Coronary heart disease

Unstable Angina
Myocardial Infarction(Heart Attack)
Sudden Cardiac death

Chronic coronary heart disease

Stable angina
Post myocardial infarction
Vasospastic angina
Ischemic cardiomyopathy
Syndrome X

Only stable angina, unstable angina, vasospastic angina and Heart attack will be discussed because those are the terms that usually put us in confusion.

Chronic Coronary Heart Disease

Stable Angina is chest pain which lasts for 2-3 minutes. The patient will have a history of chest pain for more than 6 weeks. The pain will be exerted by physical activity but the patient will feel relieved after rest and nitro-glycerine(drugs that decrease the work load of heart muscle).

To diagnose stable angina, monitor ECG and do coronary angiography (it is something like x-ray but you enter the coronary blood vessel directly and see the exact location of the narrowing of the blood vessel) if necessary.

We could hinder the progression of stable angina by our life style management. We must increase physical activity, keep control of our lipid profile, go on for a diet with greens and fruits, keep the weight under control, treat the risk factors. A patient diagnosed with stable angina can use nitro-glycerine for symptom (chest pain) control.

They will have to be on a long term management with Aspirin, statins, ACE inhibitors and Oral beta blockers.

Revascularisation may be necessary at some situations. It is an intervention by which the blood supply of heart muscle is increased.
This could be succeeded by coronary artery bypass graft or percutaneous dilatation of balloon or placing a stent. But the decision of performing an intervention depends on certain criteria such as the percent of artery that is blocked, how many artery is blocked etc.

Prinzmetal’s angina is another form of angina(chest pain) which is a vasospastic form of angina. Here the blood vessels are narrowed and there is decreased blood supply. There are no occlusions in the blood vessels. So there is nothing to do with cholesterol. But it is just the blood vessels are narrowed for unknown reasons. Medicine like nitrates and calcium channel blockers helps to dilate the narrowed blood vessels and improve the blood supply.

Acute coronary Heart Disease

Now we talk about the acute coronary heart disease which plays a very significant role in the medical field. Do not get baffled with all the medical terms. But just try to learn the essence of all the disease and your role to prevent it.
Unstable angina, Myocardial Infarction and sudden cardiac death are acute medical emergencies.

Unstable Angina is chest pain lasting more than 10minutes. It is usually of new onset but the pain usually has been only there for the past six weeks. It occurs at rest or minimal exertion and it is usually progressive i.e. pain is usually more severe this time than the previous time.
It occurs when there is plaque rupture from a atherosclerotic coronary artery (coronary artery with fatty deposition) and a thrombi is formed resulting in partial occlusion (closed) of a vessel supplying portion of the myocardium(middle and thickest layer of heart wall). So the blood supply to that part of the myocardium is impaired. Depending on the duration, collaterals (additional blood vessels) can develop and compensate the needed blood for a particular time.

To diagnose unstable angina, we do ECG and measure the cardiac markers(troponin and Creatinine kinase MB). There might be changes in the ECG but the cardiac enzymes are usually not elevated.

Treatment principle is the same as that of stable angina. A patient with unstable angina has increased risk of progressing to myocardial infarction(heart attack). So he must be on a prompt control and regular check up. One to prevent the progression of unstable angina to myocardial infarction(heart attack) must lead a very healthy life style with exercise and control over his food. To minimise the risk of developing myocardial infarction, one will be prescribed by the doctor with nitrates, beta-blockers, unfractionated heparin or low molecular weight heparin(it prevents formation of thrombi), aspirin(to prevent the aggregation of platelets).

Coronary revascularisation is done taking into account the necessary criteria as mentioned above in stable angina.

Next we shall discuss about Heart attack.

Colloquially we say heart attack but in medical terms we use the word Myocardial Infarction.

The difference between myocardial infarction (heart attack) and unstable angina is that in case of heart attack there is complete blockage of a vessel and there is complete impairment of blood supply to a particular area leading to irreversible necrosis of the heart muscle. This results in formation of scar in the myocardium. Fortunately, ECG could tell us in detail about the location of the scar. This results in myocardial infarction (Heart Attack), whereas in unstable angina there is partial occlusion of the blood vessel and a blood flow to the myocardium is present but in a low potency. Unstable angina results in unhurried expansion of ischemic changes of myocardium.

How do you differentiate if a person has got a heart attack or if it is an unstable angina?

To differentiate it, as soon as a patient arrives with chest pain we do an ECG test and measure cardiac enzymes.

Do not get puzzled with ECGs they are nothing but recordings of the electrical activity of the myocardium and different leads shows us exactly where the infarction or the ischemic changes is. But we should remember that heart attack could be without any of the above changes. In myocardial infarction, we could also know if it is acute, healing form or a chronic form using the pattern of changes in ECG.

Cardiac marker is another helpful tool in the diagnosis of heart attack. We have troponin, lactate dehydrogenase and Creatinine kinase MB are elevated. In case of unstable angina, none of the enzymes are elevated but there might be changes in the ECG.
Do not be too troubled; doctors will sort out these.

When there are changes in ECG and the troponin markers are elevated, and then you must be little alarmed not about the diagnosis or aetiology of the attack but must start focussing more on the treatment principles and prevention.

As this disease talks more of oxygen demand issues, patient should be put on rest to decrease the oxygen requirement of the myocardium. Patient must be put on strict diet control with greens and fruits, decrease intake of red meat. There are researches that shows that minimal intake of alcohol could prevent disease progression because it increases the good cholesterol about which we will talk in the forthcoming weeks.

When we talk about drugs that deals with heart attack, the first line drug we start on with is thrombolytics, which is a drug that dissolves the block that has caused the impairment of blood supply. This thrombolytics is usually contraindicated in case of unstable angina.

We have many other drugs in line such as Aspirin, clopidogrel, beta blockers, Lipid lowering agents, ACE inhibitors etc as a long term management of the Myocardial Infarction. The drugs are chosen depending on the other health issues such as Diabetes Mellitus, Hypertension and heart failure and so on.

There could be also chances a patient must have an operation called Coronary artery bypass graft (CABG) to relieve the block and there are certain criteria when an individual is suitable for a CABG. Considering how many percent of an artery is blocked, how many arteries are blocked or if the main Left ascending artery is under threat, doctors decide on operation.

As this blog says, fight against disease not by medicine but by improving the quality of life.
Heart diseases due to cholesterol are the foremost preventable diseases. We do not have microscopic eyes to look into our blood vessels or heart muscle to see what is happening there but we have enough knowledge to predict our future if we continue on the same diet rich in cholesterol and a sedentary life style.

Yes I accept it; you have enough things to worry about. To run your business, drop your kid at school, go shopping with your wife, visit your relative etc. But we must sit and think why and what are we running after?..

A tiny bit of cholesterol could make you sit on your couch lifelong with progressive failing of your heart in the future. Why to let it happen? We have thousands of websites telling you what to do and what not to do to keep away from cholesterol. But one thing I want to mention here is just about two things. Thirty minutes of exercise everyday combined with a control over your diet will keep you healthy forever.

Next blog I will meet you up with another interesting disease..