Automated ECG interpretation is the use of artificial intelligence and pattern recognition software and knowledge bases to carry out automatically the interpretation, test reporting, and computer-aided diagnosis of electrocardiogram tracings obtained usually from a patient.
The first automated ECG programs were developed in the 1970s, when digital ECG machines became possible by third-generation digital signal processing boards. Commercial models, such as those developed by Hewlett-Packard, incorporated these programs into clinically used devices.
During the 1980s and 1990s, extensive research was carried out by companies and by university labs in order to improve the accuracy rate, which was not very high in the first models. For this purpose, several signal databases with normal and abnormal ECGs were built by institutions such as MIT and used to test the algorithms and their accuracy.
The manufacturing industries of ECG machines is now entirely digital, and many models incorporate embedded software for analysis and interpretation of ECG recordings with 3 or more leads. Consumer products, such as home ECG recorders for simple, 1-channel heart arrhythmia detection, also use basic ECG analysis, essentially to detect abnormalities. Some application areas are:
The automated ECG interpretation is a useful tool when access to a specialist is not possible. Although considerable effort has been made to improve automated ECG algorithms, the sensitivity of the automated ECG interpretation is of limited value in the case of STEMI equivalent [6] [7] as for example with "hyperacute T waves", [8] de Winter ST-T complex, [9] Wellens phenomenon, Left ventricular hypertrophy, left bundle branch block or in presence of a pacemaker. Automated monitoring of ST-segment during patient transport is increasingly used and improves STEMI detection sensitivity, as ST elevation is a dynamical phenomenon.
Electrocardiography is the process of producing an electrocardiogram. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including cardiac rhythm disturbances, inadequate coronary artery blood flow, and electrolyte disturbances.
Cardioversion is a medical procedure by which an abnormally fast heart rate (tachycardia) or other cardiac arrhythmia is converted to a normal rhythm using electricity or drugs. Synchronized electrical cardioversion uses a therapeutic dose of electric current to the heart at a specific moment in the cardiac cycle, restoring the activity of the electrical conduction system of the heart. Pharmacologic cardioversion, also called chemical cardioversion, uses antiarrhythmia medication instead of an electrical shock.
Defibrillation is a treatment for life-threatening cardiac dysrhythmias, specifically ventricular fibrillation (VF) and non-perfusing ventricular tachycardia (VT). A defibrillator delivers a dose of electric current to the heart. Although not fully understood, this process depolarizes a large amount of the heart muscle, ending the dysrhythmia. Subsequently, the body's natural pacemaker in the sinoatrial node of the heart is able to re-establish normal sinus rhythm. A heart which is in asystole (flatline) cannot be restarted by a defibrillator, but would be treated by cardiopulmonary resuscitation (CPR).
Ventricular fibrillation is an abnormal heart rhythm in which the ventricles of the heart quiver. It is due to disorganized electrical activity. Ventricular fibrillation results in cardiac arrest with loss of consciousness and no pulse. This is followed by death in the absence of treatment. Ventricular fibrillation is initially found in about 10% of people with cardiac arrest.
Palpitations are perceived abnormalities of the heartbeat characterized by awareness of cardiac muscle contractions in the chest, which is further characterized by the hard, fast and/or irregular beatings of the heart.
An implantable cardioverter-defibrillator (ICD) or automated implantable cardioverter defibrillator (AICD) is a device implantable inside the body, able to perform cardioversion, defibrillation, and pacing of the heart. The device is therefore capable of correcting most life-threatening cardiac arrhythmias. The ICD is the first-line treatment and prophylactic therapy for patients at risk for sudden cardiac death due to ventricular fibrillation and ventricular tachycardia. Current devices can be programmed to detect abnormal heart rhythms and deliver therapy via programmable antitachycardia pacing in addition to low-energy and high-energy shocks.
Short QT syndrome (SQT) is a very rare genetic disease of the electrical system of the heart, and is associated with an increased risk of abnormal heart rhythms and sudden cardiac death. The syndrome gets its name from a characteristic feature seen on an electrocardiogram (ECG) – a shortening of the QT interval. It is caused by mutations in genes encoding ion channels that shorten the cardiac action potential, and appears to be inherited in an autosomal dominant pattern. The condition is diagnosed using a 12-lead ECG. Short QT syndrome can be treated using an implantable cardioverter-defibrillator or medications including quinidine. Short QT syndrome was first described in 2000, and the first genetic mutation associated with the condition was identified in 2004.
Ventricular tachycardia is a fast heart rate arising from the lower chambers of the heart. Although a few seconds may not result in problems, longer periods are dangerous; and multiple episodes over a short period of time is referred to as an Electrical Storm. Short periods may occur without symptoms, or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may result in ventricular fibrillation and turn into cardiac arrest. It is found initially in about 7% of people in cardiac arrest.
Supraventricular tachycardia (SVT) is an umbrella term for fast heart rhythms arising from the upper part of the heart. This is in contrast to the other group of fast heart rhythms - ventricular tachycardia, which start within the lower chambers of the heart. There are four main types of SVT: atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT) and Wolff–Parkinson–White syndrome. The symptoms of SVT include palpitations, feeling of faintness, sweating, shortness of breath, and/or chest pain.
The QRS complex is the combination of three of the graphical deflections seen on a typical electrocardiogram. It is usually the central and most visually obvious part of the tracing. It corresponds to the depolarization of the right and left ventricles of the heart and contraction of the large ventricular muscles.
T wave alternans (TWA) is a periodic beat-to-beat variation in the amplitude or shape of the T wave in an electrocardiogram TWA was first described in 1908. At that time, only large variations could be detected. Those large TWAs were associated with increased susceptibility to lethal ventricular tachycardias.
The Favaloro University is a private university in the city of Buenos Aires in Argentina. It was founded by surgeon René Favaloro in 1992; it obtained its definitive authorization on October 23, 2003 by decree 963/03 of president Néstor Kirchner. Favaloro did not see his project completely realised, for he committed suicide a few years before completion.
Clinical cardiac electrophysiology, is a branch of the medical specialty of cardiology and is concerned with the study and treatment of rhythm disorders of the heart. Cardiologists with expertise in this area are usually referred to as electrophysiologists. Electrophysiologists are trained in the mechanism, function, and performance of the electrical activities of the heart. Electrophysiologists work closely with other cardiologists and cardiac surgeons to assist or guide therapy for heart rhythm disturbances (arrhythmias). They are trained to perform interventional and surgical procedures to treat cardiac arrhythmia.
Computer-aided detection (CADe), also called computer-aided diagnosis (CADx), are systems that assist doctors in the interpretation of medical images. Imaging techniques in X-ray, MRI, and ultrasound diagnostics yield a great deal of information that the radiologist or other medical professional has to analyze and evaluate comprehensively in a short time. CAD systems process digital images for typical appearances and to highlight conspicuous sections, such as possible diseases, in order to offer input to support a decision taken by the professional.
Junctional ectopic tachycardia (JET) is a rare syndrome of the heart that manifests in patients recovering from heart surgery. It is characterized by cardiac arrhythmia, or irregular beating of the heart, caused by abnormal conduction from or through the atrioventricular node. In newborns and infants up to 6 weeks old, the disease may also be referred to as His bundle tachycardia or congenital JET.
Boxer cardiomyopathy is a disease of the myocardium primarily affecting Boxer dogs. It is characterized by the development of ventricular tachyarrhythmias, resulting in syncope and sudden cardiac death. Myocardial failure and congestive heart failure are uncommon manifestations of the disease.
Arrhythmias, also known as cardiac arrhythmias,heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be lightheadedness, passing out, shortness of breath or chest pain. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in sudden death.
Wireless ambulatory electrocardiography (ECG) is a type of ambulatory electrocardiography with recording devices that use wireless technology, such as Bluetooth and smartphones, for at-home cardiac monitoring. These devices are generally recommended to people who have been previously diagnosed with arrhythmias and want to have them monitored, or for those who have suspected arrhythmias and need to be monitored over an extended period of time in order to be diagnosed. Wireless Ambulatory ECGs work in a way similar to a regular ECG by measuring the electrical potential of the heart through the skin. The data is saved on an application on a Smart Phone, and then uploaded to a computer through Bluetooth or Cloud technologies. The information can also be sent through these technologies or through email to a doctor or cardiac technician. Wireless Ambulatory ECGs are able to provide voice alarm messages when cardiac abnormalities occur, such as bradycardia, and can record this information and provide a screen prompt for the patient to view the data. The devices can also store mass amounts of ECG data on the phone, replay the ECG readings at a high speed, and have a low voltage alarm function to not waste the battery life. These characteristics of the devices are seen as benefits in comparison to current ambulatory ECG monitoring equipment such as the Holter monitor.
AliveCor is a medical device and AI company producing ECG hardware and software for consumer mobile devices. The company is the first to receive FDA-clearance for a medical-device accessory to the Apple Watch.
EEG analysis is exploiting mathematical signal analysis methods and computer technology to extract information from electroencephalography (EEG) signals. The targets of EEG analysis are to help researchers gain a better understanding of the brain; assist physicians in diagnosis and treatment choices; and to boost brain-computer interface (BCI) technology. There are many ways to roughly categorize EEG analysis methods. If a mathematical model is exploited to fit the sampled EEG signals, the method can be categorized as parametric, otherwise, it is a non-parametric method. Traditionally, most EEG analysis methods fall into four categories: time domain, frequency domain, time-frequency domain, and nonlinear methods. There are also later methods including deep neural networks (DNNs).
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