A nuclear stress test is a diagnostic procedure which maps the functioning of the heart. Done on a routine basis it also helps detect the presence of any disorders in the cardiovascular system.
The organ that breathes life into the body is our human heart. Filtering and pumping blood to all the organs is the primary task of this organ. However, people who have a history of cardiovascular ailments, experience shooting chest pain, that could be a symptom of an anomalous condition in the heart. To diagnose the heart health, to check how well the heart is functioning at rest and under stress, a nuclear stress test is carried out. This test gives a visual presentation of the size of the heart chambers, the condition of the arteries and veins and damaged heart muscle, if any.
Nuclear Stress Test Procedure
A nuclear stress test is a kind of chemical stress test to evaluate the heat condition. A nuclear stress test preparation comprises two phases and is always carried out at a medical center. Below listed are the two phases of this cardiac stress test procedure, in detail:
Phase 1: The Exercise Routine
Here the patient is subjected to a physical regime in which he may be asked to walk on a treadmill or pedal on in the cycling exercise. The objective of this regime is to increase the heartbeat and blood pressure which is monitored with the help of ECG. In case, the patient is not in a state of doing rigorous exercise, the doctor prescribes dobutamine to accelerate the heartbeat. After the physical regime, the patient is given a break for a snack, before he prepares himself for the second phase of this test.
Phase 2: The Resting Period
Now the patient is injected with a radioactive substance (like thallium or sestamibi) into the veins, which enters the bloodstream and travels to the heart muscles. The patient is asked to lie down on a table under a special camera which captures images of the heart muscles by tracking down the flow of the radioactive substance in the bloodstream.The places where this substance fails to dye, indicates scarred or damaged tissue in the heart. Pertaining to the usage of thallium, this test is also referred to as thallium stress test.
Pictures of the heart taken during the exercise routine (phase 1) of this echo stress test, illustrate the ejection fraction of heart under stress, when the heart is forced to pump more blood than it normally does in rest period. Pictures of the heart during the rest period (phase 2) indicate the blood flow when the heart is at rest. The entire test takes about 4 hours and the patient is also allowed occasional breaks between scans for lunch or snacks. The above mentioned nuclear stress test is done only when the doctor suspects a coronary heart disease or blood clots in the arteries and veins of the heart.
The first significant symptoms are chest pain and shortness of breath which indicate a heart concern. If the results indicate a normal blood flow during the exercise period (phase 1) and the rest period (phase 2), then it implies that the heart condition is absolutely normal. However if the result does not show a normal blood flow during the exercise routine (phase 1), or if there is a low blood flow during both phases, then it is a clear indication that the blood flow to and from the heart is not enough. If the radioactive substance has not dyed certain areas of the heart, it clearly indicates the damaged or scarred sections of the heart. Such abnormal results following the nuclear stress test, indicate that the patient needs a revision in the medicines or might need an angioplasty or a coronary angiography or a heart bypass surgery.
Post the stress test, people experience fatigue, shortness of breath and muscle cramps followed by chest pain that is felt during the exercise routine. People who are not fit for exercise routine are injected with vasodilator drug to increase the heart palpitations. In such cases, patients may experience headache, nausea and dizziness.
Nuclear Stress Test Instructions
Whenever going for any medical tests and examination, the patient is always advised to wear loose fitting clothes. Stop taking medications (like Aggrenox), 3 days before this test. Below are a few measures to be taken prior to the nuclear stress test preparation:
1 Day Before the Test
- NO beverages (like tea or coffee)
- NO soft drinks (inclusive of those which are caffeine free)
- NO sweets (like chocolates, candies, cakes and pies)
- NO analgesics (like aspirin, Anacin or Excedrin) and persantine and theophylline type medications
In short, avoid anything that contains caffeine content.
On the Day of Test
- The patient is advised against eating or drinking anything 3 hours prior to the test. Water pills are strictly advised against.
- One must wear loose fitting clothes sans any under-wire bras (for women), jumpsuits or clothing containing metallic buttons.
- It is mandatory for the person to bring all the medications prescribed to him for earlier treatments. Also he must bring his insurance cards along.
- After the phase 1 of the nuclear stress test, the person is given a break for some time. So it is advised to get some high calorie snacks (like peanut butter sandwich), to have after the exercise routine.
- And the most important point: the patient must arrive at least 15 minutes prior to the test.
*Please note: Patients are strictly advised against consuming libido enhancing medications like Sildenafil citrate, Tadalafil and Vardenafil from 24 hours prior to the test.
There is not much risk associated with this test, but in rare cases, nuclear stress test side effects can give rise to complications like arrhythmias, increased angina pain, difficulty in breathing, fluctuating blood pressure and skin rashes. Doctors recommend this test only for people who have a history of symptomatic heart ailments. This test aids in figuring out the causes of chest pain, a symptoms which is observed in most of the cardiovascular ailments. Nuclear stress test has been very useful in treating many medical conditions concerning the heart.