Thallium stress test or nuclear stress test is a type of myocardial perfusion imaging test or nuclear radio-isotope scanning. This test monitors the patient's heart rate while at rest, and during physical activity. It evaluates the strength of the heart muscles, finds the cause of chest pain checks the severity of coronary artery blockage, condition of heart after a cardiac arrest, and its endurance during physical activities.
The test is considered to be quite safe, with low chances of estimated side effects. The amount of radiation the patient is exposed to is negligible, so the risk is also minimum, if any. The aftermath of the test is similar to the after effects of a strenuous workout or exercise.
Possible Side Effects
- The area where the intravenous (IV) was injected might start bleeding, swell, hurt, or turn red. Very rarely patients fall short of breath and develop chest pain.
- It might also cause an abnormal heartbeat, low blood pressure, leg pain, and dizziness in extreme conditions.
- Angina pain might also increase, which is a cardiac condition distinguished by chest pain due to lack of oxygen in the heart.
- The patient might face extreme fluctuations in blood pressure.
- The irregularity in heart rate called arrhythmia can also be observed. The heart rate may accelerate―known as tachycardia or slow down―called bradycardia.
Apart from all these side effects, people suffering from joint pain or other bone diseases are not recommended to take this test, as it may intensify the pain. Also, if you observe symptoms like fatigue and nausea after the radio active substance is injected in the body, immediately inform the physician or laboratory staff. Other side effects include shortness of breath and a slight or severe headache. You might also feel a mild inconvenience in the injected area like soreness during the test. An isotope treadmill stress test can diagnose diseases in nearly eighty five percent of patients suffering from coronary artery disease. Approximately 10% of patients show incorrect results. This may be the result of technical problems. Sometimes, the test may reflect inaccurate results in case of women, owing to breast tissues. Hence, they may be recommended a second test, called echo stress test. Inferior wall abnormalities might be observed in men with prominent diaphragm.
To avoid these side effects you must follow the instructions given by the health care professional and if you come across any of the symptoms like unsteady gait, skin rash, dizziness, fatigue, confusion, chest pain or any kind of inconvenience, then you should immediately inform your doctor. Patients should be mentally as well as physically prepared for the stress test to get correct and accurate results. Apart from patient's awareness, the physician, ECG technician, nurse, and laboratory staff must ensure the safety of the patient and encourage them to immediately raise an alarm in case of any discomfort faced during the stress test.