How Long Does An Ecg Test Take

A stress ECG is an electrocardiogram (synonym: exercise ergometry)which is carried out under stress, i.e. during physical activity. The load is generated by physical work on a treadmill or bicycle ergometer. Depending on the number of watts, the load corresponds to normal walking to fast cycling or jogging. The stress ECG can be used to provoke and document stress-induced cardiac arrhythmias and excitation recovery disorders.

Indications (areas of application)

  • Clarification of thoracic pain (angina pectoris; sudden pain in the heart region including vasospastic angina pectoris) in myocardial ischemia (reduced blood flow) in coronary heart disease (coronary artery disease)
  • In patients with cardiac risk factorse.g. suspected coronary artery disease, arterial hypertension (high blood pressure)
  • After myocardial infarction (myocardial infarction) to assess prognosis, physical activity, medication and cardiac rehabilitation
  • After revascularization (Revascularization) – restoring blood flow – through interventional techniques or aortocoronary bypass surgery to assess residual ischemia (remaining inadequate blood flow)
  • Assessment of physical exercise capacity (physical performance capacity)
  • examination of asymptomatic men > 40 years or women > 50 years of age before physical training
  • In occupations where disease has an impact on public safety (e.g. bus drivers, pilots)
  • In patients with cardiac arrhythmias, in whom arrhythmias often first appear during exercise (e.g., ventricular tachycardia in arrhythmogenic right ventricular disease, coronary artery disease)
  • Work trials in patients with frequency-adaptive pacemaker systems for setting the optimal intervention frequency
  • Detection of undesirable proarrhythmic effects – enhancement of arrhythmias of antiarrhythmic therapy
  • Measurement of power capacity (physical capacity) – in high-performance or competitive athletes by means of bicycle or treadmill ergometry

Absolute contraindications

  • Unstable angina pectoris – this is called unstable angina pectoris if the symptoms have increased in intensity or duration compared to previous angina pectoris attacks.
  • Acute peri/myo/endocarditis (pericarditis/heart muscle inflammation/pericarditis)
  • Acute myocardial infarction (heart attack; within the first two weeks)
  • Severe heart failure (cardiac insufficiency; NYHA III, IV)
  • Acute aortic dissection (wall bulge of the aorta)
  • Aneurysm of the heart or aorta
  • Severe main stem stenosis
  • Severe pulmonary hypertension (high blood pressure in the lungs)
  • Respiratory global insufficiency (marked hypoxia/deficiency of oxygen with decreased partial pressure of oxygen (pO2) and a CO2 retention with an increased partial pressure of carbon dioxide (pCO2))
  • Pulmonary embolism
  • Manifest heart defects (severe symptomatic aortic stenosis, HOCM)
  • Severe anemia (anemia of the blood)
  • General illnesses such as fever
  • Cardiac arrhythmias that cannot be controlled with medication, hypertension
  • If necessary, clarify with surgeon after surgery

Relative contraindications

  • Arterial hypertension (high blood pressure)
  • Tachy- or bradyarrhythmia (occurrence of arrhythmias with pronounced high or low pulse rates)
  • AV blockages (conduction disturbances from the atrium to the ventricle)
  • Known electrolyte disorders (deviations of one or more body fluids from the normal electrolyte concentration (salt concentration))

The procedure

Electrocardiography allows the electrical activities of all the heart muscle fibers to be derived and displayed as curves in an electrocardiogram (ECG). In the heart there is a special stimulation systemin which the electrical excitation is formed, which is then propagated through the conduction system. This enables the contraction of the heart, i.e. its pumping function. The excitation originates in the Sinus nodewhich is located in the right atrium (Latin: atrium dextrum) of the heart. The sinus node is also called the pacemaker, because it drives the heart at a certain frequency. It is controlled by the sympathetic and parasympathetic nervous systems (vagus nerve), which thus significantly influence the heart rhythm. From the sinus node, the electrical impulse travels via fiber bundles to the AV node (atrioventricular node). This is located at the junction with the ventricles (heart chambers) and regulates the transmission of impulses to the heart chambers. The period of excitation conduction is called atrioventricular conduction time (AV time). This corresponds to the duration of the PQ time in the ECG. If the sinus node fails, the AV node can take over the function as the primary rhythm generator. The heart rate is then 40-60 beats per minute. If there is a severe delay in the transmission of impulses by the AV node or if it fails, the clinical picture known as AV block occurs. The electrical impulses are transmitted by means of electrodes (suction electrodes; adhesive electrodes). The electrodes (number: 10) are placed on the chest for this purpose. An ECG device amplifies these impulses and either displays them as an ECG curve (electrocardiogram) on a screen or prints them out on a strip of paper. Before starting the exercise, a resting ECG is written and the resting pulse and blood pressure are determined prior to exercise. The patient is then tested, for example, on a bicycle ergometer according to the WHO scheme (ergometer test). Here, the wattage, i.e. the load, is continuously increased by 25 watts at regular intervals of two minutes. In addition to recording the ECG, the pulse (= heart rate) and blood pressure are measured at the same time to provide further valuable information about the performance of the heart. The minimum heart rate that should be achieved during a seated exercise ECG is calculated as follows: maximum heart rate (Hfmax): [220 minus age in years] per minute. Caveat (attention): bradycardic drugs (drugs that lower the heart rate; discontinue sufficiently long beforehand if possible).

Discontinuation criteria

  • Angina pectoris (German: Brustenge; heart pain)
  • Symptoms: progressive dyspnea (shortness of breath), cyanosis, dizziness, cold sweats, ataxia (movement disorder)
  • Absence of rate increase
  • Blood pressure drop of more than 10 mmHg or lack of systolic blood pressure rise
  • Blood pressure > 240 mmHg systolic; > 115 mmHg diastolic
  • ECG
    • Increase in arrhythmias (volleys, ventricular tachycardia (VT), increasing supraventricular extrasystoles (SVES), atrial fibrillation/flutter
    • AV block, new onset left bundle branch block.
    • ST elevations > 0, 1mV; horizontal ST depressions > 0.2 mV
  • Physical exhaustion
  • Reaching maximum heart rate (= defined exercise level in watts)

Also in the recovery phase ECG and blood pressure continue to be recorded regularly about every two minutes for up to ten minutes after the end of exercise. The duration of the examination is between 15-30 minutes, depending on the patient’s exercise tolerance. The stress ECG is then evaluated. The duration of exertion, total power, maximum exertion level, changes in heart rate and blood pressure, as well as heart rhythm and ECG changes are recorded. In addition, reasons for any discontinuation are listed and any complaints are recorded.

Interpretation of the measured values

Power The maximum target power is for man 3 watts/kg body weight minus 10% for each decade of life beyond age 30. The target power for women is 2.5 watts/kg body weight minus 8% for each decade of life beyond age 30. ECG The ECG can be used to make a variety of statements about characteristics and diseases of the heart. It should be noted that the surface ECG only indicates the electrical activity of the myocardium and does not reflect the actual ejection fraction. Notes on the morphology of the ECG curve See under resting ECG. Indications of coronary artery disease (CHD) in the exercise ECG:

  • ST segment:
    • New onset descending or horizontal ST depression (≥ 0.1 mV, 80 msec after the J point).
    • Ascending ST-segment (depression ≥ 0.15 mV, 80 msec after the J point).
  • Clinical symptoms of CHD: angina (chest tightness, heart pain) and/or dyspnea (shortness of breath).

Sensitivity (percentage of ill patients in whom the disease is detected by the application of the procedure, i.e. a positive finding occurs) 50-80% and specificity (probability that actually healthy persons who do not suffer from the disease in question are also detected as healthy by the procedure) 60-80% of the stress ECG is significantly higher than with the resting ECG. ECG changes and their possible interpretations are detailed in the respective clinical picture. Blood pressure Definition of threshold values for hypertension (high blood pressure) after stress response

Systolic (mmHg) Diastolic (mmHg)
Stress response according to Franz
100 W to 50 years ≥ 200 ≥ 100
Inflow per decade over 50 10 5
Stress response according to Rost and Kindermann (systolic only). ≥ 145 + 1/3 age + 1/3 watt power. < 90

Further notes

  • Those who developed blood pressure peaks (systolic value > 210 mmHg (men) and > 190 mmHg (women); as long as the blood pressure peaks occurred in the third minute of a 3-minute exercise level, respectively) despite antihypertensive therapy under ergometer testing or or physical exercise are at risk of developing hypertension and left ventricular hypertrophy (LVH; pathological enlargement of the left ventricle) [1].

Heart rate Endurance capacity is a reflection of the functional reserve capacity of the heart. It is characterized by a rapid recovery capacity as indicated by the pulse response after the end of exercise (recovery pulse). The assessment refers to the decrease in heart rate 1, 3 or 5 minutes after exercise:

Decline in heart rate after 5 minutes. Rating
< 20 poor
20 – 30 moderate
30 – 35 sufficient
35 – 45 good
45 – 50 very good
> 50 excellent


  • The stress ECG has to be used in the context of the ischemia diagnostics has a sensitivity of about 50% and a specificity of more than 80%.
  • Imaging modalities such as stress echo, stress perfusion MRI, dobutamine stress MRI, myocardial perfusion SPECT, and CT angiography are clearly superior to exercise ECG with a sensitivity of more than 80% without sacrificing specificity.
  • The ESC guideline recommends with a pretest probability of coronary artery disease (CAD) of:
    • 15-65%: if possible, a modern imaging modality such as stress echo, stress MRI, or myocardial perfusion SPECT; alternatively, exercise ECG; if the pretest probability is 15-50%, CT angiography is also recommended as an alternative.
    • 66-85 %: diagnostic imaging should always be sought.
    • > 85 %: invasive coronary angiography (form of x-ray examination in which the coronary arteries (arteries that surround the heart in a ring shape and supply the heart muscle with blood) are imaged; performed as part of a cardiac catheterization (CCU)).
  • Nachanalysis of the SCOT Heart Study in patients with stable angina pectoris [2]:
    • A stress ECG is particularly helpful if it is pathological (abnormal)!
    • If the findings are normal or inconclusive, further clarification is required!
    • The negative predictive value of the stress ECG is 96%, in relation to any obstructive coronary heart disease (CHD) 82%.


  1. Mizuno R et al: Clinical importance of detecting exaggerated blood pressure response to exercise on antihypertensive therapy. Heart 2016;102:849-854.
  2. Singh T et al: Exercise Electrocardiography and Computed Tomography Coronary Angiography for Patients With Suspected Stable Angina Pectoris A Post Hoc Analysis of the Randomized SCOT-HEART Trial. JAMA Cardiol. Published online June 3, 2020. doi:10.1001/jamacardio.2020.1567


  1. Sechtem U et al: Commentary on the 2013 European Society of Cardiology (ESC) guidelines on the management of stable coronary artery disease (CAD). Cardiology 2015 – 9:159-164 doi 10.1007/s12181-015-0652-x Published online: 27 February 2015.

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Further information

Prevention – early detection

Exercise ECG is used to analyze the effect of physical activity on the heart. Bicycle ergometers or treadmills are usually used for this purpose. Below you will find more detailed information about the examination and some practical advice.

What is the exercise test?

  • The exercise electrocardiogram (ECG) is also called the stress test and is performed while you are physically exerting yourself.
  • During the test, you will perform a series of physically demanding exercises on a bicycle ergometer or treadmill. During this process, your heartbeat and blood pressure will be measured.


  • The test allows you to evaluate your heart’s blood flow under stress. This can help detect damage to the heart.

How can you prepare for the test at home?

  • Follow the instructions given to you during the doctor’s consultation regarding taking your prescribed medications. Depending on the case, the intake of the medication will be continued or interrupted after consultation with your doctor.
  • If the examination takes place after lunch, you should only eat something light. In general, you should not drink alcohol or caffeine before the examination and refrain from tobacco use.
  • For the stress test, wear comfortable shoes and loose sportswear that can be easily opened in the upper body area.
  • You may leave unaccompanied after the test and resume your normal activities. However, you are advised to have a family member or acquaintance pick you up if you feel too exhausted.

How does the examination proceed?

  • The examination is performed with a simple device in a treatment room.
  • You sit down on the bicycle ergometer or stand on the treadmill.
  • Self-adhesive electrodes are attached to your chest and a blood pressure monitor is attached to your arm.
  • The doctor will then explain the function of the device and the exercise rhythm to be followed.
  • These preparations are followed by an initial recording of the electrocardiogram and a blood pressure measurement at rest.
  • Initially, the exercise is performed with a light load. This increases as the exercise progresses.
  • Let your examining physician know how you feel. You will be asked about this on a regular basis.
  • In order to come to rest, you should continue to perform the movements without load for a few minutes at the end of the exercise. The recording of the data is not completed until the original resting values have been reached.
  • The examination is painless, but requires an effort.

How long does the examination take?

  • The examination takes about 10 to 15 minutes and the preparations about 15 minutes.
  • Plan to rest for about an hour after the test.

The stress ECG does not require any special preparation by you and is performed directly in your doctor’s office. However, you should remember to wear comfortable clothing. Publication date: 05.05.13 Date modified: 13.04.11

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A healthy lifestyle is the best hypertension therapy

Poorly treated high blood pressure promotes the development of cardiovascular disease. The goal of hypertension therapy is to reduce the risk of secondary diseases by lowering blood pressure levels below 140/90 mm/Hg. The treatment goal is lower in the presence of concomitant diseases. The measures presented here are often sufficient to return blood pressure to normal in cases of mild hypertension. In any case, a healthy lifestyle supports the effectiveness of drug treatment. Read more This website does not replace a visit to the doctor! © AndreyPopov Berlin, updated 08.09.2022 – The electrocardiogram is one of the most important examination methods in medicine. It can detect cardiac arrhythmias and provide indications of thickened heart walls or circulatory disorders. In emergency situations, it is used to diagnose or rule out heart attacks. But how does the ECG work? The sinus node, the heart’s clock generator, is located on the right atrial wall of the heart. It sends electrical impulses that travel across the heart to keep it beating steadily. During an electrocardiogram (ECG), electrodes measure how the heart’s currents spread and recede through the organ. The electrodes are attached to the chest, arms and legs and record electrical excitation at the surface of the skin. They relay this information to a recording device. Finally, they are displayed graphically as a wave line on a monitor or ECG paper. From the waveform, doctors can tell how often and how fast the heart is beating. They can also see whether patients have extra beats or arrhythmias such as atrial fibrillation. The ECG curve can also indicate whether blood flow to the heart vessels may be impaired. An ECG can be performed quickly in many doctors’ offices and does not cause pain.

Here’s how the heart works.

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The ECG types

The electrocardiogram can be used in many ways. With the help of the following three common examination methods, it is possible to find out whether patients are healthy or suffering from arrhythmia or other heart problems. The sinus node is the heart’s clock generator. Normally, it triggers small electrical impulses that spread through the heart along a defined path. The electrocardiogram (ECG) measures these heart currents. open in dialog box

ECG curve with healthy sinus rhythm

In a healthy heart, a typical recurring curve is visible in the ECG. The first small wave shows how the currents propagate in the atria. The large ripple represents how the currents propagate in the ventricles. open in dialog box

ECG curve in atrial fibrillation

In atrial fibrillation, the surges occur not only at the sinoatrial node, but also at other sites. The irregular stimuli cause the atria to beat much faster than normal. This is seen on an electrocardiogram. The stress ECG is a special form of electrocardiogram in which the electrical processes of the heart are recorded so that conclusions can be drawn about muscle strength, blood flow, frequency and rhythm of the heart. The examination of the cardiovascular system under controlled stress conditions is of particular importance. During the so-called stress ECG, the electrical heart currents are recorded while the patient is physically active. The question is answered: How well does the heart work under stress? An overview of the most important things to know about this topic.

What is a stress ECG?

An exercise ECG is based on the same principle as a resting ECG. The electrical processes of the heart are also recorded during the stress ECG. This involves checking how the electrical activity of the heart changes during physical exertion – under defined conditions – and to what extent the cardiovascular system is able to adapt to the increased oxygen demand. The patient’s electrical cardiac activity is recorded via electrodes during physical activity. An ECG before and after simple physical exertion such as knee bends or climbing stairs can be used as an orientation. As a rule, however, a stationary bicycle (bicycle ergometer) is used: the dynamic load triggers an increase in cardiac output and oxygen demand.

When is an exercise ECG necessary?

Some heart diseases only manifest themselves under physical exertion. In particular, if coronary heart disease (CHD) is suspected, an exercise ECG may be indicated, since a resting ECG is often unremarkable and evaluated without pathological findings. In contrast, an exercise ECG may reveal arrhythmias or ECG changes. Indications for performing an exercise ECG may include:

  • Evidence of ischemic reactions: diseases of the coronary vessels (coronary heart disease, CHD)
  • to assess blood pressure behavior during exercise (for example, to objectify poor performance in arterial hypertension or to assess the risk of hypertrophic cardiomyopathy)
  • to assess the individual cardiopulmonary exercise capacity
  • if exercise-induced hypertension is suspected
  • Suspicion of exercise-induced cardiac arrhythmias
  • Exercise capacity and control after myocardial infarction or heart surgery

Exercise ECG: Preparation

Before physical exertion and recording of an exercise ECG, a preliminary examination including a detailed medical history, clinical findings and performance of a resting ECG is always necessary so that possible risks due to not yet detected or already existing diseases can be detected or excluded at an early stage. The following technical requirements are initially necessary for the procedure of a stress ECG:

  • a bicycle ergometer (in Germany, bicycle ergometry is most widely used, whereas in the USA, treadmills are more common)
  • monitoring of exercise capacity by means of multichannel ECG recording
  • the measurement of blood pressure and heart rate
  • a table to determine the desired heart rate and tolerable blood pressure
  • emergency medication and a defibrillator so that resuscitation readiness can be ensured

In addition, it is important to maintain standardized conditions in the examination room, such as room temperature, humidity, etc.

Exercise ECG: Procedure

First, several wired electrodes are attached to the patient’s chest, arms and legs, and a blood pressure cuff is placed on the upper arm. The patient is then asked to pedal on a special bicycle, the bicycle ergometer. By increasing the resistance on the bike, the load, which is individually adapted to the patient, is increased and the power achieved by the patient is measured in watts. Different load phases can be set on the bicycle ergometer and can be equivalent to the following physical loads in everyday life: 25 to 50 watts: normal to brisk walking 75 to 100 watts: Stair climbing or slow cycling 125 to 150 watts: Jogging or fast cycling more than 150 watts: Heavy athletic exertion Every two minutes, the load is increased by 15 watts. The load is increased until the maximum heart rate, calculated from the following formula, is reached: Maximum age-appropriate heart rate = 220 – age (years) +/- ten to twelve heartbeats per minute. The table presented below shows the target values for maximum power (watts) with increasing load; by age, gender and body weight. The maximum power achieved represents an important parameter in exercise diagnostics and can be considered a good predictor in the severity assessment of a disease. Watt values for women

Age / Weight 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64
40-45 110 105 100 95 90 90 85 75 75
49-49 115 110 105 100 100 95 90 85 80
50-53 120 115 110 105 100 100 95 90 85
54-57 125 120 120 115 110 105 100 100 95
58-61 130 125 125 120 115 115 105 100 100
62-65 135 135 130 125 120 120 110 110 105
66-69 140 140 135 130 130 125 120 115 110
70-73 150 145 140 135 130 130 125 120 115
74-77 155 150 145 140 135 135 130 125 120
> 78 160 155 150 150 145 140 135 130 130

Watt values for men

Age / Weight 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64
60-65 200 210 200 185 175 170 155 150 135
66-69 225 215 205 195 180 175 160 155 140
70-73 230 220 210 200 190 180 165 160 145
74-77 235 225 215 205 195 185 170 165 150
78-81 240 230 220 210 200 190 170 170 150
82-85 245 235 225 215 205 195 185 175 160
86-89 250 240 230 220 210 200 190 180 170
90-93 255 245 235 225 215 205 195 185 175
> 94 260 250 240 230 220 210 200 190 180

Exercise ECG: Duration

The duration for recording an exercise ECG is approximately 15 minutes. Continuous ECG display, observation of the patient, monitoring of heart rate and blood pressure during the examination are necessary to stop the cycle ergometry immediately if the patient experiences any discomfort. At the end of the examination, the patient is followed up for at least six minutes. The extent to which and whether the pulse and blood pressure return to normal after physical exertion is documented. During the period after physical exertion, complications such as cardiac arrhythmias or a drop in blood pressure may occur.

Exercise ECG: Discontinuation Criteria

As mentioned above, cycle ergometry should be discontinued early if the patient experiences subjective symptoms. Subjective symptoms include, but are not limited to:

  • Dizziness
  • Ataxia (= disturbance of movement coordination)
  • Muscular or general physical fatigue
  • progressive chest tightness (angina pectoris)
  • progressive shortness of breath
  • pallor
  • Cyanosis (bluish discoloration of skin and mucous membranes due to lack of oxygen in the blood)
  • cold sweating

Other discontinuation criteria include objective findings involving ECG changes (for example, complex ventricular arrhythmias or a new onset of left bundle branch block) and hemodynamics (progressive drop in blood pressure, inadequate rise in blood pressure, or excessive rise in blood pressure).

Exercise ECG: Evaluation

The exercise ECG generally has low sensitivity and, especially in women, low specificity. An unremarkable exercise ECG does not necessarily rule out coronary insufficiency. The findings of an exercise ECG should therefore always be interpreted in the context of the patient’s clinical symptoms and should also take into account any cardiovascular risk factors present. Cardiovascular risk factors include:

  • arterial hypertension
  • diabetes mellitus
  • dyslipidemia (= lipid metabolism disorder in which the composition of blood lipids is shifted)
  • Nicotine addiction
  • Lack of exercise

In principle, the patient’s ability to cope with stress in daily life should also be taken into account as a yardstick for the examination. The above-mentioned formula (220 – patient’s age) is used to determine the individual target value of exercise capacity, from which the patient’s exercise limit is derived. The ECG shows the conduction of excitation within the heart; it is possible to identify different sections on the basis of the curve of the ECG, through which, in turn, it is possible to draw conclusions about the electrophysiological processes in the heart. Normal ECG findings In a normal ECG finding, a so-called P wave, which is produced by the spread of excitation in the atria of the heart and usually appears positively on the ECG as a semicircular rash, is followed by a QRS complex. The QRS complex is a sharply serrated complex and represents the depolarization of both ventricles: Q morphology is always negative, R is always positive, and S is always negative. The QRS complex is followed by the T wave, which corresponds to the excitation regression of the ventricles. It is followed by the P wave again. Possible pathologies in the ECG findings Pathologies (pathological processes) can also be detected on the basis of the ECG findings. Only a few examples are given below:

  • A missing P wave, for example, shows that no excitation of the atria has taken place and possible causes for this can be certain medications (for example beta-blockers), but also heart diseases such as coronary heart disease (CHD) or atrial fibrillation.
  • If, on the other hand, an increase in the P wave is detectable on the ECG, this may also be the result of an enlarged right atrium of the heart and may be manifested by pulmonary diseases such as COPD, pulmonary fibrosis or pulmonary hypertension.
  • a shortened PQ duration may indicate sinus tachycardia and a prolonged PQ duration may indicate 1st degree AV block: AV block, atrioventricular block, is a common cardiac arrhythmia in which the propagation of excitation from between the atria and the ventricles is temporarily or permanently delayed.
  • If an increase in amplitude of R and/or S can be detected in the ECG, this is referred to as hypertrophy signs (signs of organ enlargement), which can indicate the presence of left or right heart hypertrophy.

Stress ECG: Costs

The costs for the examination including the evaluation of a stress ECG by means of bicycle ergometry with increasing stress amount to approximately 60 to 70 euros for those insured by the state as an IGeL – individual health service. If the performance of a stress ECG is medically indicated, the statutory health insurance covers the costs. How Long Does An Ecg Test Take.

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