Q1. WHAT IS CORONARY ANGIOGRAPHY?

Coronary angiography is an X-ray procedure used to examine the coronary arteries – the blood vessels that supply blood to your heart muscle. During the procedure, an image (called an angiogram) is displayed on a monitor, showing the doctor what your coronary arteries look like.

Although ‘angiogram’ is the name of the image and ‘angiography’ is the name of the procedure, many people refer to the test as an angiogram.

Q2. WHY IS CORONARY ANGIOGRAPHY DONE?

The main reason for doing coronary angiography is to check the health of your coronary arteries and see if there are any blockages or areas of narrowing. The procedure may also show up some problems with the way the valves and muscular walls of your heart are working, or may show a cardiac aneurysm (a bulging of the heart wall) or a birth defect such as a hole in the inner wall (septum) separating the chambers of the heart.

As well as being used to diagnose problems with the coronary arteries, coronary angiography can be used to treat certain conditions, if done using the technique of cardiac catheterisation. For example, a procedure known as angioplasty can be done, where narrowed or blocked coronary arteries are dilated by inflating a tiny balloon on the tip of the catheter, often followed by the placement of a stent (a tiny wire mesh tube that helps keep the artery open). These types of procedures can’t be done during CT coronary angiography, because this doesn’t involve the use of a catheter.

Coronary angioplasty and stenting is a treatment used to widen and open up narrowed or blocked arteries supplying your heart muscle.

During angioplasty and stenting, the narrowed artery is stretched open with a balloon (angioplasty), and a metal strut (stent) is implanted into the coronary artery. This keeps the narrowing open and allows your blood to flow more freely through it.

• Percutaneous transluminal coronary angioplasty (PTCA)

• Percutaneous coronary intervention (PCI)

Like all organs in the body, the heart needs a constant supply of blood. The heart has its own network of blood vessels known as the coronary arteries.

In adults, these arteries can become narrowed and hardened. This is known as atherosclerosis, which can restrict the flow of blood to the heart and lead to angina.

While many cases of angina can be treated with medication, a coronary angioplasty may be required to restore the blood supply to the heart in severe cases. Coronary angioplasties are also often used as an emergency treatment after a heart attack.

• Relieve your symptoms of discomfort, pain, tightness and heaviness.
• Reduce your need for angina medication.
• Ease symptoms such as breathlessness.
• Enable you to be more active.
• Improve your ability to do everyday activities, such as climbing stairs and walking any distance.

• Make you feel generally better so you’re more able to do the things you want to do, such as going to work and enjoying a social life.

Fractional Flow Reserve, or FFR, is a guide wire-based procedure that can accurately measure blood pressure and flow through a specific part of the coronary artery. FFR is done through a standard diagnostic catheter at the time of a coronary angiogram (a.k.a. cardiac catheterization). The measurement of Fractional Flow Reserve has been shown useful in assessing whether or not to perform angioplasty or stenting on “intermediate” blockages.

The point of opening up narrowings or blockages in the coronary arteries is to increase blood flow to the heart. But a number of studies have shown that if a “functional measurement”, such as Fractional Flow Reserve, shows that the flow is not significantly obstructed, the blockage or lesion does not need to be revascularized (angioplasty) and the patient can be treated safely with medical therapy.

A very thin guide wire is inserted through a standard 4F or 5F diagnostic catheter during an angiogram. Because of the smaller size catheter necessary, this can be done as an outpatient procedure.

The special guide wire crosses the lesion and is able to measure the flow and pressure of the blood, after infusion of a hyperemic agent, such as adenosine. Results are displayed on a special monitor (left) along with the “FFR value”. Studies have shown that an FFR value less than 0.75 or 0.80 corresponds to inducible ischemia, and most likely will require interventional treatment. Blockages that score above this threshold can be safely and adequately treated by medical therapy without the need for angioplasty.

Intravascular Ultrasound (or IVUS) allows us to see a coronary artery from the inside-out. This unique point-of-view picture, generated in real time, yields information that goes beyond what is possible with routine imaging methods, such as coronary angiography, performed in the cath lab, or even non-invasive Multislice CT scans.

This cross-section view can aid in stent sizing, and in confirmation that the stent has been placed optimally, is fully expanded and hugging the vessel wall. A growing number of cardiologists feel that the new information yielded by IVUS can make a significant difference in how a patient is treated, and can provide for more accurate stent placement, reducing complications and the incidence of stent thrombosis.

Intravascular ultrasound is done in the catheterization laboratory in conjunction with angiography. Some cardiologists use it occasionally, in difficult cases, or to assist in the selection and sizing of stents and balloons. Others use it routinely, to confirm accurate stent placement and optimal stent deployment.

During a heart attack, blood flow to the heart is blocked, often by a blood clot or a buildup of plaque in the arteries.

Since the heart muscle needs oxygen to survive, when blood flow is blocked, the muscle begins to die. This is why heart attack sufferers need to be rushed into surgery to resolve the obstruction and restore blood flow.

Symptoms may start slowly and persist for hours, days, or weeks before the heart attack. The heart continues to beat, but because of the blockage, it is not receiving all the oxygen-rich blood it requires.

Symptoms may start slowly and persist for hours, days, or weeks before the heart attack. The heart continues to beat, but because of the blockage, it is not receiving all the oxygen-rich blood it requires. Not everyone has the same symptoms. About ⅔ of people have chest pain or shortness of breath, or they feel tired days or weeks before the heart attack.

During a heart attack, you may feel pain in the middle of the chest that can spread to the back, jaw, or arms. Or you may feel pain in these places and not in your chest. Sometimes people feel pain in their stomach and mistake the heart attack for indigestion.

In cardiac arrest, the heart stops beating and needs to be restarted.While a heart attack is a circulation problem, cardiac arrest is an electrical problem triggered by a disruption of the heart’s rhythm. Most heart attacks do not lead to cardiac arrest. However, when cardiac arrest happens, a heart attack is a common cause.

In many cases, cardiac arrest is a temporary condition experienced during a medical emergency. It is not necessarily preceded by heart disease, but many patients experience warning symptoms up to a month before cardiac arrest.

Because cardiac arrest stops the heart from beating, the brain, lungs, and other organs do not get the blood and oxygen they need. Cardiac arrest can lead to death within minutes if not treated.

Symptoms of cardiac arrest include dizziness, loss of consciousness, and shortness of breath. Within seconds of cardiac arrest, a person will become unresponsive and have trouble breathing.

Hypoglycemia is a condition caused by a very low level of blood sugar (glucose), your body’s main energy source.

Hypoglycemia is often related to the treatment of diabetes. However, a variety of conditions — many rare — can cause low blood sugar in people without diabetes. Like fever, hypoglycemia isn’t a disease itself — it’s an indicator of a health problem.

Immediate treatment of hypoglycemia is necessary when blood sugar levels are at 70 milligrams per deciliter (mg/dL) or 3.9 millimoles per liter (mmol/L) or below. Treatment involves quick steps to get your blood sugar level back into a normal range either with high-sugar foods or drinks or with medications. Long-term treatment requires identifying and treating the underlying cause of hypoglycemia.

High blood pressure, or hypertension, is when the force of the blood pushing on the blood vessel walls is too high. When someone has high blood pressure:

• The heart has to pump harder.
• The arteries (blood vessels that carry the blood away from the heart) are under greater strain as they carry blood.After a while, high blood pressure can damage the heart, brain, kidneys, and eyes. Finding and treating high blood pressure early can help people stay healthy.

Most of the time, no specific cause is found. This is called essential hypertension. When a cause is found, high blood pressure usually is from:

• Kidney disease
• Lung problems
• Heart problems
• Obesity
• Some medicines

While high blood pressure is most common in adults, teens can have it too. High blood pressure can run in families.

An electrophysiological (EP) study is a test which looks at your heart’s electrical activity in more detail.

It’s used to diagnose and treat a wide variety of abnormal heart rhythms.

An EP study is carried out in a cath lab by a specialist cardiac doctor called an electrophysiologist. It usually takes about 2-3 hours, but can take longer. You’ll be asked not to eat or drink anything for a few hours beforehand.

• Thin flexible tubes called catheters are inserted into a vein, usually in the groin. You’ll have a local anaesthetic injection to numb the area where the catheters are put in. You may also be given a sedative to help you relax during the procedure.
• The catheters are passed up to the heart. This can induce an arrhythmia (an abnormal heart rhythm).
• You may feel lightheaded or like you’re having palpitations. You may also feel a sensation or discomfort in your chest. You should tell the staff if you experience any symptoms.