HPA Magazine 11
One of the areas that has developed most, in recent years in medicine, are complementary diagnostic tests. They are the "weapons" that determine the accuracy and precision of diagnosis, but also of treatment. In this edition we will provide information that allows our readers to clarify and better understand some complementary tests, allowing additional confidence and cooperation when having to do them. Let's start with the heart.
This is a test that uses ultrasound to get real-time images of the heart and of the largest blood vessels. Its necessity is due to your doctor’s previous medical evaluation and request.
It evaluates the morphological and functional alterations in the cardiac chambers, valves, vessels and structures close to the heart when the heart is at rest (the complete examination involves 2D and Doppler techniques and possibly "M-Mode"). If it is considered necessary and technically possible (it is not always), an analysis with Stress technology (assessment of myocardial deformity) will be performed.
A trained professional will use an echocardiographer to collect the necessary images. A gel is used to obtain these images (it is water based and hypoallergenic). Electrodes are placed to monitor the electrical activity of the heart correlating with the images collected. You will be asked to remove your shirt and to move in various positions to get the best pictures. The examination is carried out in an area specifically designed for these exams in order to collect the best images while ensuring the patient’s privacy. The examination itself is painless and non-invasive. Current transthoracic echocardiography requires the use of Doppler technology (mapping of blood flow, making it possible, for example, to determine its velocity) obtaining all the necessary information.
It varies depending on the reason why the exam was requested and what is being discovered during the exam. A complete transthoracic echocardiogram requires two phases: the collection of images and the completion of the report. The image collection phase itself may take from 15 to 60 minutes, depending on the complexity of the case.
Transoesophageal Echocardiogram (TEE) is an examination in which images of the heart are obtained by means of a special ultrasound probe, which is introduced through the mouth into the oesophagus under sedation. During the TEE the probe can better visualise certain parts of the heart. The whole procedure takes approximately one hour. However, usually the ultrasound probe will remain in the oesophagus for approximately 10 to 15 minutes.
The procedure is performed by a team consisting of a cardiologist, a nurse and a cardio pneumology technician.
The professionals should be advised if you have any oesophagus disease, if you have had surgery or have had any treatment in that area or if you have difficulty swallowing. You should also mention if you have any allergies, any clotting abnormalities, or if you are taking anticoagulant medication. It is vital that you have fasted (fluid and solid) for at least 6 hours before the procedure. You will also be asked to remove any prosthesis or dental plates before beginning the exam.
It is imperative that you give your informed consent (without this signed document the examination will not be carried out) and also inform the team of the presence of any of the above conditions.
Throughout the procedure your vital signs will be monitored (oxygen level, blood pressure and reaction to medication).
An intravenous tube will be placed in the arm (which is not painful), where you will be given a sedative to help you relax.
Your throat will be anesthetised with a special spray. You should swallow this liquid and no saliva from this moment, due to the risk of choking. The exception will be when the doctor asks you to swallow.
A small plastic protector will be placed between your teeth, through which the probe will be inserted, and you will be asked to lie on your side during the procedure.
The catheter will be inserted through your mouth into the oesophagus until it reaches the back of the heart (you should assist in the passage of the catheter and when asked by the doctor to "swallow"). Ultrasound imaging of the heart, heart valves, and blood flow will then be obtained and recorded.
According to the images that are being obtained, it may be necessary to perform certain manoeuvres, which will be explained to you.
The effects of the sedation usually disappear within a few hours. The risks associated with performing a TEE are rare, but they do exist. For a few days after the examination you may notice some discomfort in the throat ("scratchy" throat, hoarseness) which is associated with the passage of the catheter. Possible rare risks include inflammatory/infectious processes, perforation of the oesophagus, oesophageal haemorrhages, cardiac arrhythmias and exceptionally fatal situations.
You will not be able to eat or drink anything for about two hours after the procedure because your throat may still be numb.
You will not be able to drive for the rest of the day and it is advisable not to sign legal documents on the day of the exam.
It will be necessary to arrange for someone to take you home after the procedure, as you may feel numb from the sedative.
The examination report will be made available to you later, after the specialist has analysed all the images.