what are the indications for a stress test

Full Answer

Do you really need a stress test?

You may need a stress test if you’re at risk for heart disease or have symptoms like shortness of breath with exertion or discomfort in the chest and other areas of the body. “A stress test is called for when the patient reports atypical symptoms, particularly patients with diabetes and family history of premature coronary artery disease,” he says.

Can you eat and drink before a stress test?

What Should I Eat Before A Stress Test? Yes. You should not eat or drink anything except water for four hours before the test. Avoid all products containing caffeine for 24 hours before the test. In general, caffeine is found in coffee, tea, colas, and other soft drinks, most chocolate products, and most other beverages.

What does a failed stress test indicate?

When you have trouble completing the stress test in a specified period of time, it may indicate that your heart is not receiving enough blood. Reduced blood flow can be caused by several different heart conditions, some of which are very serious. How Many Minutes Is Good On A Stress Test?

What are indications for terminating stress test?

Indications for terminating the test include if the patient request to stop due to severe symptoms (i.e., chest pain, shortness of breath or fatigue), severe exercise-induced hypotension or hypertension, horizontal or downsloping ST depression of greater than or equal to 1 mm or ST-segment elevation, new bundle branch block, AV block ...

How long does it take for an acute myocardial infarction to occur?

Acute myocardial infarction (AMI) within 48 hours – due to risk of aggravating the infarction, as well as inducing ventricular arrhythmias.

What is the term for pulmonary infarction in acute phase?

Pulmonary infarction in acute phase – due to risk of aggravating the condition. Perimyocarditis (myocarditis) in acute phase – due to risk of arrhythmias. Severe aortic stenosis – due to risk of syncope, ischemia and arrhythmias. Endocarditis – due to risk of embolization.

What is the 12 lead ECG?

The 12-lead resting ECG recorded before exercise is recorded using Mason-Likar’s limb lead placement ( Figure 1, below), which implies that the limb leads are placed on the torso, instead of distally on the limbs ( ECG limb lead placement has been discussed). Removal of chest hair will improve the quality of the recording.

What is required before exercise?

Physical examination and anamnesis must be obtained before the start of exercise. Cardiopulmonary auscultation is mandatory. Symptoms, medications, medical history, allergies and contraindications must be scrutinized carefully. Blood pressure is measured at rest before the start of exercise.

Why should beta blockers not be withheld?

Note that beta-blockers should not be withheld in patients conducting the test in order to assess functional capacity and cardiovascular response. The purpose of the test in that scenario is namely to assess capacity during optimal circumstances.

Do beta blockers affect heart rate?

In some circumstances it is necessary to withhold cardioactive medications during the exercise test. Beta blockers have a negative inotropic effect (i.e reduces contractility) and a negative chronotropic effect (i.e reduces heart rate).

What is exercise testing?

Assessment of therapeutic response. Exercise testing can be used to evaluate the effect of medications or interventions such as PCI, CABG, CRT etc.

What Are the Indications for Exercise Stress Testing?

The following is a summary of guidelines for stress testing that have been proposed by several professional organizations.

What does it mean to have a CHD and new or worsening symptoms?

Patients with known CHD and new or worsening symptoms–i.e. if there has been a clinical change (ie , new or worsening symptoms) in a patient with known CAD.

What should patients with active cardiac conditions undergo prior to elective noncardiac surgery?

Patients undergoing elective non-cardiac surgery – For preoperative evaluation of patients prior to elective noncardiac surgery, patients with active cardiac conditions should undergo evaluation (including stress test) and treatment prior to the planned surgery.

What is exercise testing used for?

Exercise testing has been used for the provocation and identification of myocardial ischemia for >6 decades , and during this time additional purposes for testing have evolved. Exercise testing now is used widely for the following:

Is stress testing appropriate for heart failure?

Patients with newly diagnosed heart failure or cardiomyopathy – Stress testing is indicated and appropriate to evaluate for ischemic heart disease as the cause for heart failure or a cardiomyopathy of uncertain etiology, assuming that coronary angiography has not already been planned or performed.

Is exercise testing a cardiovascular test?

During the past several decades, exercise testing has been focused increasingly on assessment of cardiovascular risk, not simply detection of coronary obstruction. Ultimately, improved clinical outcome is a major goal of exercise testing. Reference.

Is cardiac stress testing appropriate?

Assessment of response after medical or surgical interventions in patients with valve disease, arrhythmias, or other heart diseases. Cardiac stress testing for screening of asymptomatic low-risk patients is generally not indicated or appropriate.

How does a treadmill work?

walks slowly in place on a treadmill. Then the speed is increased for a faster pace and the treadmill is tilted to produce the effect of going up a small hill.

What are the things that are monitored during an EKG?

Heart rate, breathing, blood pressure, electrocardiogram (ECG or EKG), and how tired you feel are monitored during the test.

What test is used to predict heart attack risk?

Depending on the results of the exercise stress test, the physician may recommend more tests such as a nuclear stress test or cardiac catheterization.

What is the purpose of stress test?

A physician may recommend an exercise stress test to: Diagnose coronary artery disease. Diagnose a possible heart-related cause of symptoms such as chest pain, shortness of breath or lightheadedness. Determine a safe level of exercise.

Why does the heart pump more blood?

As your body works harder during the test, it requires more oxygen, so the heart must pump more blood. The test can show if the blood supply is reduced in the arteries that supply the heart. It also helps doctors know the kind and level of exercise appropriate for a patient. A person taking the test:

How long does dipyridamole last?

Dipyridamole blocks the cellular uptake of adenosine. Its half-life is 30 to 35 minutes, metabolized primarily by the liver, and excreted in small amounts by urine. It is administered via an infusion pump at the dose of 140 mcg/kg per minute for 4 minutes with a maximum dose of 0.56 mg/kg. The radionuclide is administered 3 to 5 minutes after the infusion. Aminophylline is often used as a reversal agent to reduce side effects. Simultaneous low-level exercise improves image quality, allows us to assess exercise capacity, and risk-stratify future cardiac events.

How are myocardial perfusion images obtained?

Myocardial perfusion images are obtained during rest and after stress with either exercise or pharmacological agents, preferably vasodilators. Both the images are then compared to detect myocardial perfusion, viability, and global left ventricular systolic function, which generally signifies the presence and extent of coronary artery disease.

What is radionuclide MPI?

Radionuclide MPI provides essential information on myocardial perfusion at rest and exercise or pharmacological testing with the help of a radioactive tracer.

What are the two types of cardiac stress medications?

Broadly speaking, there are two types, vasodilator or inotropic/chronotropic drugs.

How long does adenosine infusion take?

It is administered via infusion pump at the dose of 140 mcg/kg/minute, typically over six minutes, then radionuclide is injected over 10 seconds, and adenosine infusion is continued for additional 3 minutes.[8] A shorter duration protocol of 4 minutes has been studied and has shown equally effective results. Simultaneous low-level exercise is safe, well-tolerated, and provides improved image quality.

What are the two modalities of stress?

There are primarily two modalities of stress – exercise or pharmacological.

What is the role of nuclear stress testing in CAD?

Patients with intermediate probability for CAD are most likely to benefit from additional cardiovascular testing.[5]  Nuclear stress testing plays an important role in determining the management of these patients, especially when revascularization is being considered.

What is dipyridamole used for?

Dipyridamole was the first vasodilator used for myocardial perfusion stress testing. It is an indirect coronary artery vasodilator. It increases the tissue levels of adenosine by preventing the intracellular reuptake of adenosine by inhibiting enzyme adenosine deaminase prolonging its vasodilator effect and increasing adenosine blood levels. [9][10]

How long does adenosine infusion last?

The dose of adenosine used during a pharmacologic stress testing is 140 mcg/kg/min, and it is given continuously for 6 minutes duration. The radioactive material is normally given at 3 minutes, and then adenosine is kept infusing for 3 more minutes. There is an additional methodology in which adenosine is given for 4 minutes as a continuous infusion, and its effects and outcomes are comparable to the continuous infusion lasting for 6 minutes.[7]  Adenosine generally produces a modest increase in heart rate and a modest decrease in blood pressure. The infusion results in a 3.5- to 4-fold increase in coronary blood flow over baseline. The half-life of adenosine is less than 10 seconds. [1]

How long does dipyridamole last?

The alpha half-life (the initial decline following peak concentration) is approximately 30 to 45 minutes. The beta-half life (the terminal decline in plasma concentration) is approximately 10 hours. It is metabolized in the liver to glucuronic acid conjugate and excreted in the bile.

When was Regadenoson approved?

Regadenoson is a newer vasodilator agent approved by the FDA in 2008 and most routinely used today due to its selective action on A2A receptors and lesser side-effects.

What is the systolic pressure of uncontrolled hypertension?

Uncontrolled hypertension (systolic pressure of over 200 mmHg or a diastolic pressure of over 110 mmHg)

How long does it take to inject dipyridamole?

The dose of dipyridamole is 0.142 mcg/kg/min, or 0.57 mcg/kg.[9]  Dipyridamole is infused over 4 min, with the radiotracer being injected 3 to 5 min after the completion of the dipyridamole infusion. Symptoms may last for a longer time than other vasodilators (15 to 25 minutes).

Why is exercise stress not helpful?

Exercise stress testing is also not very helpful in patients with an insufficient hemodynamic response to exercise due to abnormalities involving the respiratory system, and having ongoing issues involving muscles, bones, and vessels in the peripheral system. Also, the exercise stress test is not useful when baseline EKG is abnormal such as with left ventricular hypertrophy (LVH), left bundle branch block (LBBB), paced rhythm, Wolff Parkinson White (WPW) syndrome, or greater than 1 mm ST-segment depression. These patients are suitable candidates for testing involving pharmacologic agents. Pharmacologic stress testing is used in combination with imaging modalities such as radionuclide imaging and echocardiography.

What is the purpose of a heart evaluation?

1. Evaluation of exercise capacity in children or adolescents with congenital heart disease, those who have had surgery for congenital heart disease, and children who have acquired valvular or myocardial disease. 2. Evaluation of the rare child with a description of anginal chest pain.

What is the age group of CAD?

Patients older than 65 years are usually defined as “elderly.” One possible subdivision of this group is the “young old” (65 to 75 years) and the “old old” (older than 75 years); CAD is highly prevalent in symptomatic patients in both groups. Pharmacological stress testing is more often required in the elderly because of their inability to exercise adequately.

Why do you need exercise after bypass surgery?

After coronary artery bypass surgery, exercise testing may be used in symptomatic patients to distinguish between cardiac and noncardiac causes of recurrent chest pain , which is often atypical after surgery. If a management decision is to be based on the presence of ischemia, the exercise ECG may suffice.

Why is pharmacological stress testing more often required in the elderly?

Pharmacological stress testing is more often required in the elderly because of their inability to exercise adequately. Interpretation of exercise tests in the elderly differs somewhat from that in younger patients. Resting ECG abnormalities may compromise the accuracy of diagnostic data from the ECG.

What is a tachyarrhythmia?

1. Evaluation of the adequacy of the response to medical, surgical, or radiofrequency ablation treatment for children with a tachyarrhythmia that was found during exercise testing before therapy. 2. As an adjunct in assessment of the severity of congenital or acquired valvular lesions, especially aortic valve stenosis.

Is exercise ECG necessary for myocardial revascularization?

Patients who undergo myocardial revascularization should have documented ischemic or viable myocardium, especially if they are asymptomatic. The exercise EC G is useful in these circumstances, particularly if the patient has multivessel disease and the culprit vessel does not need to be defined. However, in the setting of one-vessel disease, sensitivity of the exercise ECG is frequently suboptimal, especially if the revascularized vessel supplies the posterior wall. Moreover, use of the exercise ECG is inappropriate when the culprit vessel must be defined.

Is exercise required for valvular disease?

In symptomatic patients with documented valvular disease, the course of treatment is usually clear and exercise testing is not required. However, the expanding use of Doppler echocardiography has greatly increased the number of asymptomatic patients with well-defined valvular abnormalities. The primary value of exercise testing in valvular heart disease is to objectively assess atypical symptoms, exercise capacity, and extent of disability, all of which may have implications for clinical decision making. This is particularly important in the elderly, who may not have symptoms because of their limited activity. Use of the exercise ECG for diagnosis of CAD in these situations is limited by false-positive responses due to LVH and baseline ECG changes.