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34-568: Holter may refer to: Holter monitor , ambulatory health monitor Holter (surname) Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Holter . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Holter&oldid=1165859333 " Category : Disambiguation pages Hidden categories: Short description

68-534: A cardiac event monitor which can be worn for a month or more can be used. When used to study the heart, much like standard electrocardiography, the Holter monitor records electrical signals from the heart via a series of electrodes attached to the chest. Electrodes are placed over bones to minimize artifacts from muscular activity. The number and position of electrodes varies by model, but most Holter monitors employ between three and eight. These electrodes are connected to

102-582: A cardiac radiologist, a nuclear medicine physician, a nuclear medicine technologist, a cardiology technologist, a cardiologist, and/or a nurse. The typical dose of radiation received during this procedure can range from 9.4 to 40.7 millisieverts . The American Heart Association recommends ECG treadmill testing as the first choice for patients with medium risk of coronary heart disease according to risk factors of smoking, family history of coronary artery stenosis, hypertension, diabetes and high cholesterol. In 2013, in its "Exercise Standards for Testing and Training",

136-535: A cardiopulmonary exercise test include evaluation of shortness of breath, workup before heart transplantation , and prognosis and risk assessment of heart failure patients. The test is also common in sport science for measuring athletes' maximal oxygen consumption, V̇O 2 max . In 2016, the American Heart Association published an official scientific statement advocating that cardiorespiratory fitness , quantifiable as V̇O 2 max and measured during

170-438: A cardiopulmonary exercise test, be categorized as a clinical vital sign and should be routinely assessed as part of clinical practice. The CPX test can be done on a treadmill or cycle ergometer . In untrained subjects, V̇O 2 max is 10% to 20% lower when using a cycle ergometer compared with a treadmill. A nuclear stress test uses a gamma camera to image radioisotopes injected into the bloodstream. The best known example

204-527: A controlled clinical setting. This stress response can be induced through physical exercise (usually a treadmill) or intravenous pharmacological stimulation of heart rate. As the heart works progressively harder (stressed) it is monitored using an electrocardiogram (ECG) monitor. This measures the heart's electrical rhythms and broader electrophysiology . Pulse rate, blood pressure and symptoms such as chest discomfort or fatigue are simultaneously monitored by attending clinical staff. Clinical staff will question

238-411: A response in stenotic vessels. This difference in response leads to a steal of flow and perfusion defects appear in cardiac nuclear scans or as ST-segment changes. The choice of pharmacologic stress agents used in the test depends on factors such as potential drug interactions with other treatments and concomitant diseases. Pharmacologic agents such as adenosine, regadenoson (Lexiscan), or dipyridamole

272-627: A significantly lower resolution than those from a standard 12-lead ECG, and in some cases have been shown to provide misleading ST segment representation, even though some devices allow setting the sampling frequency up to 1000 Hz for special-purpose examinations such as detection of "late potential". Another innovation is the inclusion of a triaxial movement sensor, which records the patient's physical activity and, on examination and software processing, extracts three movement statuses: sleeping, standing, or walking. Some modern devices can record spoken patient diary entries that can be listened to. After

306-636: A small piece of equipment that is attached to the patient's belt or hung around the neck, keeping a log of the heart's electrical activity throughout the recording period. A 12-lead Holter system is used when precise ECG information is required to analyse the exact origin of the abnormal signals. The Holter monitor was developed at the Holter Research Laboratory in Helena, Montana , by experimental physicists Norman J. Holter and Bill Glasscock, who started work on radio telemetry in 1949. Inspired by

340-433: A suggestion from cardiologist Paul Dudley White in the early 1950s, they redirected their efforts toward development of a wearable cardiac monitoring device. The Holter monitor was released for commercial production in 1962. Older monitors used reel-to-reel tapes or C90 or C120 audio cassettes , moving at a 1.7 mm/s or 2 mm/s speed to record the data. The recording could be played back and analyzed at 60 times

374-417: A treadmill test using ECG / electrophysiology metrics and nuclear testing, each have unique sensitivity and specificity values. The treadmill test, employing the modified Bruce protocol , demonstrates a sensitivity range of around 73-90% and a specificity range of around 50-74%. Sensitivity refers to the percentage of individuals with the condition correctly identified by the test, while specificity denotes

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408-412: Is myocardial perfusion imaging . Typically, a radiotracer ( Tc-99 sestamibi , Myoview or thallous chloride 201 ) may be injected during the test. After a suitable waiting period to ensure proper distribution of the radiotracer, scans are acquired with a gamma camera to capture images of the blood flow. Scans acquired before and after exercise are examined to assess the state of the coronary arteries of

442-706: Is a competitive antagonist of the A2A adenosine receptor and can attenuate the vasodilatory effects adenosine. Aminophylline may be used to attenuate severe and/or persistent adverse reactions to adenosine and regadenoson. Cardiac stress testing, used since the 1960s, has a history rooted in the diagnostic and prognostic assessment of patients with suspected coronary artery disease . It has evolved to evaluate inducible myocardial ischemia as an indicator of adverse outcomes. The factors influencing mortality risk have changed over time due to decreasing angina symptoms, increasing prevalence of conditions like diabetes and obesity , and

476-503: Is a heart attack. According to the American Heart Association, a significant percentage of individuals, approximately 65% of men and 47% of women, present with a heart attack or sudden cardiac arrest as their first symptom of cardiovascular disease. Consequently, stress tests performed shortly before these events may not be highly relevant for predicting infarction in the majority of individuals tested. Stress cardiac imaging

510-423: Is different from Wikidata All article disambiguation pages All disambiguation pages Holter monitor The Holter's most common use is for monitoring ECG heart activity (electrocardiography or ECG). Its extended recording period is sometimes useful for observing occasional cardiac arrhythmias which would be difficult to identify in a shorter period. For patients having more transient symptoms,

544-513: Is generally used when a patient cannot achieve adequate work level with treadmill exercise, or has poorly controlled hypertension or left bundle branch block . However, an exercise stress test may provide more information about exercise tolerance than a pharmacologic stress test. Commonly used agents include: Regadenoson or dobutamine is often used in patients with severe reactive airway disease ( asthma or COPD ) as adenosine and dipyridamole can cause acute exacerbation of these conditions. If

578-469: Is not recommended for asymptomatic, low-risk patients as part of their routine care. Some estimates show that such screening accounts for 45% of cardiac stress imaging, and evidence does not show that this results in better outcomes for patients. Unless high-risk markers are present, such as diabetes in patients aged over 40, peripheral arterial disease , or a risk of coronary heart disease greater than 2 percent yearly, most health societies do not recommend

612-410: Is performed both before and after the exercise so that structural differences can be compared. A resting echocardiogram is obtained prior to stress. The ultrasound images obtained are similar to the ones obtained during a full surface echocardiogram, commonly referred to as transthoracic echocardiogram . The patient is subjected to stress in the form of exercise or chemically (often dobutamine ). After

646-522: The 1970s, provides an estimate of the patient's post-test likelihood of disease. Stress tests have limitations in assessing the significance and nature of cardiac problems, they should be seen in context - as an initial assessment that can lead to a number of other diagnostic approaches in the broader management of cardiac diseases. According to data from the US Centers for Disease Control and Prevention (CDC) common first systems of coronary artery disease

680-560: The AHA indicated that high frequency QRS analysis during ECG treadmill test have useful test performance for detection of coronary heart disease. The common approach for stress testing recommended by the American College of Cardiology and the American Heart Association involves several methods to assess cardiac health. These methods provide information for diagnosing and managing heart-related conditions. Two primary stress tests utilized are

714-573: The heart such as various types of fascicular blocks. A "normal" stress test does not offer any substantial reassurance that a future unstable coronary plaque will not rupture and block an artery, inducing a heart attack . As with all medical diagnostic procedures, data is only from a moment in time. A primary reason stress testing is not perceived as a robust method of CAD detection — is that stress testing generally only detects arteries that are severely narrowed (~70% or more). A stress test may be accompanied by echocardiography . The echocardiography

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748-533: The number of leads may be minimised for patient comfort. Two or three channel recording has been used for a long time in the Holter monitoring history; 12-channel Holters were introduced later, using either the standard 12-lead electrocardiograph or the modified (Mason-Likar) exercise lead system. These Holters can occasionally provide information similar to that of an ECG stress test examination. They are also suitable when analyzing patients after myocardial infarction . Recordings from these 12-lead monitors are of

782-456: The patient pressed the patient button). Advanced systems also perform spectral analysis, ischemic burden evaluation, graph of patient's activity or PQ segment analysis. Also possible is the ability to monitor and analyse pacemaker impulse detection, useful for checking pacemaker function. Cardiac stress test A cardiac stress test is a cardiological examination that evaluates the cardiovascular system's response to external stress within

816-516: The patient throughout the procedure asking questions that relate to pain and perceived discomfort. Abnormalities in blood pressure, heart rate, ECG or worsening physical symptoms could be indicative of coronary artery disease . Stress testing does not accurately diagnose all cases of coronary artery disease, and can often indicate that it exists in people who do not have the condition. The test can also detect heart abnormalities such as arrhythmias , and conditions affecting electrical conduction within

850-423: The patient's asthma is treated with an inhaler then it should be used as a pre-treatment prior to the injection of the pharmacologic stress agent. In addition, if the patient is actively wheezing then the physician should determine the benefits versus the risk to the patient of performing a stress test especially outside of a hospital setting. Caffeine is usually held 24 hours prior to an adenosine stress test, as it

884-518: The patient. By showing the relative amounts of radioisotope within the heart muscle, the nuclear stress tests more accurately identify regional areas of reduced blood flow. Stress and potential cardiac damage from exercise during the test is a problem in patients with ECG abnormalities at rest or in patients with severe motor disability. Pharmacological stimulation from vasodilators such as dipyridamole or adenosine, or positive chronotropic agents such as dobutamine can be used. Testing personnel can include

918-467: The percentage of individuals without the condition correctly identified as not having it. The nuclear stress test exhibits a sensitivity of 81% and a specificity ranging from 85 to 95%. To arrive at the patient's post test likelihood of disease, the interpretation of the stress test result necessitates the integration of the patient's pretest likelihood with the test's sensitivity and specificity. This method, initially introduced by Diamond and Forrester in

952-457: The record, particularly with rapid patient movement, impeding processing. Other factors can also affect signal quality, such as muscle tremors, sampling rate and resolution of the digitized signal (high quality devices offer higher sampling frequency). The automatic analysis commonly provides the physician with information about heart beat morphology, beat interval measurement, heart rate variability , rhythm overview and patient diary (moments when

986-457: The recording of ECG signal for typically 24 hours, the signal must be analysed. A person would have to listen for the full 24 hours; instead integrated automatic analysis determines different sorts of heart beats, rhythms, etc. The success of the analysis is closely associated with the signal quality, which mainly depends upon the attachment of the electrodes to the patient's body. Incorrect attachment allows electromagnetic disturbance to add noise to

1020-434: The recording speed, so 24 hours of recording could be analyzed in 24 minutes. Modern monitors record EDF-files on digital flash memory . The information is loaded on a computer, which counts ECG complexes; calculates summary statistics, such as average, minimum, and maximum heart rate; and finds parts of the recording that are worthy of further study. Each Holter system has hardware (called monitor or recorder) for recording

1054-418: The signal, and software for review and analysis of the record. There may be a "patient button" on the front that the patient can press at specific instants such as feeling/being sick, going to bed, taking pills, marking an event of symptoms which is then documented in the symptoms diary, etc.; this records a mark that identifies the time of the action on the recording. Advanced Holter recorders are able to display

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1088-460: The signal, useful for checking the signal quality. The size of the recorder differs depending on the manufacturer of the device. The average dimensions of today's Holter monitors are about 110x70x30 mm, but some are only 61x46x20 mm and weigh 99 g. Most Holter Monitors monitor the ECG via two or three channels. Depending on manufacturer, different lead systems and numbers of leads are used;

1122-434: The target heart rate is achieved, 'stress' echocardiogram images are obtained. The two echocardiogram images are then compared to assess for any abnormalities in wall motion of the heart. This is used to detect obstructive coronary artery disease. While also measuring breathing gases (e.g., oxygen saturation , maximal oxygen consumption), the test is often referred to as a cardiopulmonary exercise test. Common indications for

1156-569: The test as a routine procedure. Absolute contraindications to cardiac stress test include: Indications for termination: A cardiac stress test should be terminated before completion under the following circumstances: Absolute indications for termination include: Relative indications for termination include: Side effects from cardiac stress testing may include Pharmacologic stress testing relies on coronary steal . Vasodilators are used to dilate coronary vessels, which causes increased blood velocity and flow rate in normal vessels and less of

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