Heart stress test

Thallium-201 is a radioisotope used by medical professionals to determine the health of a persons heart. During a thallium-201 scan, also called a heart stress test, a patient performs physical activity and is injected with thallium-201 one to two minutes before stopping the activity. The isotope emits gamma rays that are recorded by a detector to display a two-dimensional image of the heart and its blood supply. If gamma rays are not detected in certain areas in and around the heart, the areas are considered cold. This means that the blood supply has been impeded or blocked, a condition that often leads to heart attack or stroke. 

Moderate risk Has three or more risk factors for coronary artery disease Has moderate, stable angina Had a recent myocardial infarction or stroke within the past 6 weeks Has moderate congestive heart failure (NYHA Class 2) Fbtient should undergo a complete cardiovascular work-up and treadmill stress testing to determine tolerance to increased myocardial energy consumption associated with increased sexual activity... 

Another main use is the radioisotope TlCl-201, with the relatively short half-life of about 73 hours, in cardiac stress tests to identify potential heart abnormalities. TlCl-201 has an ability to bind with the heart muscle, but only if the heart is receiving an adequate supply of... 

The Candidate Physical Ability Test is the next step in the process for many fire departments some put this step first. You should expect to have a medical clearance, or at the very least sign a medical waiver stating that you are in good enough shape to undertake this stressful test, before you will be allowed to participate. The fire department wants to make sure that no one has a heart attack in the middle of the test. So, you can expect the test to be tough. 

Pritzker M, The penile stress test a window to the heart of the man [abstract].Circulation 1999 100 3751. 

The antiplatelet/antithrombotic activity of dipyridamole has been demonstrated in laboratory and in animal models, and has been shown to inhibit platelet aggregation and vessel-wall thrombogenesis [9-11]. Dipyridamole has been given either alone or with aspirin in the management of myocardial infarction and stroke. For the secondary prevention of stroke or transient ischemic attack, the drug may be given as a modified-release preparation in a dose of 200 mg twice daily. Dipyridamole administered intravenously results in a marked coronary vasodilation and is used in stress testing in patients with ischemic heart disease [5]. 

The patient, a 63-year-old Caucasian female, was hospitalized on 4 April 2002 though 10 April 2002 for a non-ST segment elevation myocardial infarction (non-Q-wave MI per chart documentation). She had a negative adenosine stress test after the initial event. Her serum cardiac-specific troponin I (cTnl) concentration 24 hours after her onset of chest pain was 1.4 pg/L (upper limit of normal is 0.3 ng/mL), and her creatine kinase (CK) MB level was 12.5 pg/L (upper limit of normal 6.0 ng/mL). Three days post-event her cTnl level was 0.5 pg/L and her CK-MB level was 4.5 pg/L (Fig. 5-1). MB refers to one of the isoenzyme forms of CK found in serum. The form of the enzyme that occurs in brain (BB) does not usually get past the blood-brain barrier and therefore is not normally present in the serum. The MM and MB forms account for almost all of the CK in serum. Skeletal muscle contains mainly MM, with less than 2% of its CK in the MB form. MM is also the predominant myocardial creatine kinase and MB accounts for 10%-20% of creatine kinase in heart muscle. 

Toft J, Mortensen J, Hesse B. Risk of atrioventricular block during adenosine pharmacologic stress testing in heart transplant recipients. Am J Cardiol 1998 82(5) 696-7. 

Balan KK, Critchley M. Is the dyspnea during adenosine cardiac stress test caused by bronchospasm Am Heart J 2001 142(l) 142-5. 

In 47 consecutive patients (mean age 64 years, 46 men) with three or more cardiovascular risk factors, intravenous dobutamine was given at a rate of 40micro-grams/kg/minute until the target heart rate was achieved, which took a mean of 11.6 minutes (4). Subjective sensations occurred in 49% of the patients (palpitation 21%, chest pain 6%, nausea 6%, headache 6%, dizziness 13%), while half the patients had abnormal cardiac rhythms (ventricular extra beats 38%, supraventricular tachycardia 10%, and non-sustained ventricular tachycardia 2%). The authors concluded that the safety and tolerability of this procedure is comparable to that of standard dobutamine stress testing, although its specificity and selectivity are still uncertain. 

Repeated use of an oxjmetazoline nasal spray has been associated with changes in fetal heart rate demonstrated as a non-reactive, non-stress test and late decelerations in a patient at 41 weeks of gestation 6 hours after the last dose these changes gradually disappeared (4). 

During a stress test, thallium-201 is injected into the patient s bloodstream to determine if his or her heart is working properly. IMAGE COPYRIGHT 2009, MONKEY BUSINESS IMAGES. USED UNDER LICENSE FROM SHUTTERSTOCK.COM. 

Thallium-201 is used by doctors to determine how well a person s heart is working. In many cases, the isotope is used as part of a stress test. Thallium-201 is injected into the patient s bloodstream as he or she exercises on a treadmill or bicycle. As soon as the exercise ends, the patient lies down. A large camera is passed over the body. The camera records the radiation given off by the isotope. This record shows whether the patient s heart is working properly or not. 

For years, doctors have used a variety of devices, such as X-ray imaging, to get a view inside a person s body. Nuclear reactions have enabled them to get a much more detailed view of the body. For example, doctors can take a close look at a person s heart by using a thallium stress test. The person is given an intravenous injection of thallium-201, which acts chemically like calcium and collects in the heart muscle. As the thallium-201 decays, low-energy gamma rays are emitted and are detected by a special camera that produces images, such as the one shown in Figure 19. 

Blocker and calcium channel blocker therapy may interfere with the heart rate response to dobutamine stress tests and is... 

Chaitman B. Exercise stress testing. In Braunwald E, ed. Heart Disease A Textbook of Cardiovascular Medicine, 4th ed. Philadelphia, Saunders, 1992 161-179. 

Adenosine Negative chronotropic effect Hypersensitivity Effect on sinus node of denervated heart Life-threatening asystole (>0.5 min) may occur if used to treat supraventricular arrhythmia or stress testing... 

A 48-year-old male presents to the clinic because of concerns about heart disease. He reports that his father died from a heart attack at age 46, and his older brother has also had a heart attack at age 46 but survived and is on medications for elevated cholesterol. The patient reports chest pain occasionally with ambulation around his house and is not able to climb stairs without significant chest pain and shortness of breath. The physical exam is normal, and the physician orders an electrocardiogram (ECG), exercise stress test, and blood work. The patient s cholesterol result comes back as 350 mg/dL (normal 200). The physician prescribes medication, which he states is directed at the rate-limiting step of cholesterol biosynthesis. 

The use of nuclear perfusion imaging in addition to exercise stress testing or as an alternative modality for patients unable to exercise (using pharmacologic agents) can provide important prognostic information for patients with chronic ischemic heart disease. 

A nuclide with the symbol assess a patient s heart in a stress test. 

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