Dobutamine Stress Echo

Echocardiography is a diagnostic procedure that helps to detect, assess and evaluate problems related to the blood vessels, heart and valve function. Depending upon the technique used to carry out the procedure, echocardiography can be differentiated into various types, stress echo being one of them. Unlike normal stress echo, in which the patient is asked to exercise on a treadmill or a stationary bike while the echo is recorded, Dobutamine stress echoinvolves the use of a medicine called Dobutamine to stimulate your heart in the same manner as it does on exertion during exercise. It is an alternative for people who are unable to exercise owing to some physical or medical shortcoming.

Why is the procedure performed?

Dobutamine stress echo may be performed for any of the following reasons:

• To determine how well the patient’s heart works under stress
• To determine the risks of having a coronary artery disease in future
• To evaluate the progress of a cardiac treatment plan
• To assess the degree to which a heart valve disease has progressed
• To detect any structural or functional abnormalities in the heart and heart valves.
• To estimate the peri or post-operational risks in advance of the cardiac surgery
• To detect any irregularity in the blood flow.

Getting ready for the procedure

• The patient is briefed about the procedure and asked to give his/her consent for the same.
• The patient might be required to fast for a couple of hours prior to the test. Use of tobacco and consumption of caffeine is strictly restricted as these can interfere with the test results.
• The patient needs to inform the doctor if he/she
• is allergic or sensitive to any medicine
• is on any medication or supplements
• has a pacemaker
• is pregnant (for women)
• has undergone heart surgery in the past
• has a history of some major heart disease
• The patient needs to remove all the jewellery and ornaments before the procedure.
• The patient will be required to wear a hospital gown during the procedure

How is the procedure performed?

A Dobutamine stress echocardiogram is carried out by using one of the following echocardiogram techniques or a combination of two or more of these:

• M-mode Echocardiogram- It is a standard type of echo that helps to generate the trace lines rather than the actual image of the heart. The procedure can help to measure the size of various heart structures, including the thickness of the heart walls.
• Doppler echocardiogram- It involves the use of high-frequency soundwaves to measure and assess the flow of blood in the major blood vessels throughout the body. It can help to detect any abnormality in the flow of blood which is usually linked to vascular or Valvular blockage.
• Colour Doppler- Colour Doppler is an advanced form of a Doppler echocardiogram. As the name suggests, the procedure helps to generate colourful images to depict the direction of the flow of blood.
• 2-D (two-dimensional) Echocardiogram- It helps to generate a cone-shaped echo view which enables the doctors to see the real-time motion of the various structures of the heart.
• 3-D (three-dimensional) Echocardiogram- It helps to view the various heart structures with greater depth by generating live or real-time images of the same.

What are the various steps involved?

• Initially, the patient is asked to lie on his/her left side, however, the position may be changed during the procedure. Dobutamine is administered along with some other fluids intravenously.
• The patient is connected to an ECG monitor with the help of small electrodes for tracing and recording the electrical activity of the heart. Vital signs like heart rate, blood pressure and breathing rate are monitored simultaneously.
• A special gel is applied on the patient’s chest followed by placing the transducer and moving it back and forth. The gel helps to reduce the air between the skin and the transducer thereby adding to the accuracy of the procedure.
• The amount of Dobutamine, as well as the pace at which it is administered, depends upon the weight of the patient. The rate of infusion is increased every few minutes until the target heart rate is achieved and the infusion is stopped.
• The transducer is moved to have a better view of all the areas of the heart.
• ECG tracing is continued for 10 to 15 minutes until the patient returns to a baseline state. This is followed by recording the final echo.

Risks involved

Some of the risks associated with Dobutamine stress echocardiogram include:

• Slight pain or discomfort in the chest
• Elevated blood pressure
• Irregularity in heartbeat
• Light-headedness
• Nausea
• Fatigue and tiredness
• Slight risks of cardiac arrest (very rare)