If it is not a sinus rhythm, then determining the rhythm is necessary before proceeding with further interpretation. Some arrhythmias with characteristic findings:. The heart has several axes, but the most common by far is the axis of the QRS complex references to "the axis" imply the QRS axis. Each axis can be computationally determined to result in a number representing degrees of deviation from zero, or it can be categorized into a few types. The QRS axis is the general direction of the ventricular depolarization wavefront or mean electrical vector in the frontal plane.
It is often sufficient to classify the axis as one of three types: normal, left deviated, or right deviated. The normal QRS axis is generally down and to the left , following the anatomical orientation of the heart within the chest. An abnormal axis suggests a change in the physical shape and orientation of the heart or a defect in its conduction system that causes the ventricles to depolarize in an abnormal way.
All of the waves on an ECG tracing and the intervals between them have a predictable time duration, a range of acceptable amplitudes voltages , and a typical morphology. Any deviation from the normal tracing is potentially pathological and therefore of clinical significance.
It may also affect the high frequency band of the QRS. The earliest sign is hyperacute T waves, peaked T waves due to local hyperkalemia in ischemic myocardium. Over a period of hours, a pathologic Q wave may appear and the T wave will invert. Over a period of days the ST elevation will resolve.
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Pathologic Q waves generally will remain permanently. The left anterior descending LAD artery supplies the anterior wall of the heart, and therefore causes ST elevations in anterior leads V 1 and V 2. An ECG tracing is affected by patient motion.
Some rhythmic motions such as shivering or tremors can create the illusion of cardiac arrhythmia. Distortion poses significant challenges to healthcare providers,  who employ various techniques  and strategies to safely recognize  these false signals. Improper lead placement for example, reversing two of the limb leads has been estimated to occur in 0.
Numerous diagnoses and findings can be made based upon electrocardiography, and many are discussed above. Overall, the diagnoses are made based on the patterns. For example, an "irregularly irregular" QRS complex without P waves is the hallmark of atrial fibrillation ; however, other findings can be present as well, such as a bundle branch block that alters the shape of the QRS complexes.
ECGs can be interpreted in isolation but should be applied — like all diagnostic tests — in the context of the patient. For example, an observation of peaked T waves is not sufficient to diagnose hyperkalemia; such a diagnosis should be verified by measuring the blood potassium level. Conversely, a discovery of hyperkalemia should be followed by an ECG for manifestations such as peaked T waves, widened QRS complexes, and loss of P waves.
The following is an organized list of possible ECG-based diagnoses. The word is derived from the Greek electro , meaning related to electrical activity; kardia , meaning heart; and graph , meaning "to write". From Wikipedia, the free encyclopedia. Not to be confused with other types of electrography or with echocardiography.
Main article: Cardiac electrophysiology. Main article: Electrocardiography in myocardial infarction.
ACC/AHA Clinical Competence Statement on Electrocardiography and Ambulatory Electrocardiography
Archived from the original on 2 October Retrieved 11 February Basic arrhythmias 7th ed. Saunders Co.. ECG Medical Training. Retrieved 24 June Textbook of veterinary medical nursing. Oxford: Butterworth-Heinemann. Preventive Services Task Force recommendation statement". Annals of Internal Medicine. Federal Aviation Administration. Retrieved 27 December MIT Technology Review.
Retrieved 1 April Retrieved 25 August Stanford Health Care. Journal of the American College of Cardiology. Society for Cardiological Science and Technology. Retrieved 21 October Retrieved 24 May Retrieved 27 May Nurses Learning Network. Cables and Sensors. Retrieved 11 July Pediatric and Fundamental Electrocardiography.
Developments in Cardiovascular Medicine. Retrieved 15 August Archived from the original on 22 March December Advances in Physiology Education. Estonian Journal of Engineering. Clinical Cardiology. Tex Heart Inst J. Hodder Education. J Am Coll Cardiol.
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International Journal of Cardiology. Physio-Control, Inc. Journal of Medical Case Reports. American Heart Journal. Batchvarov, Marek Malik, A. Birse, rev. Patricia E. Alexandernn Muirhead — Oxford, Blackwell: privately printed J Physiol. Arch Neerl Sc Ex Nat. Origins, pioneers, and contributors".
N Engl J Med. Clinics of the Virginia Mason Hospital. Taro Takemi". Takemi Program in International Health. Atlas of cardiovascular monitoring.
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Book Category Outline. Valve repair Valvulotomy Mitral valve repair Valvuloplasty aortic mitral Valve replacement Aortic valve repair Aortic valve replacement Ross procedure Percutaneous aortic valve replacement Mitral valve replacement Percutaneous pulmonary valve implantation production of septal defect in heart enlargement of existing septal defect Atrial septostomy Balloon septostomy creation of septal defect in heart Blalock—Hanlon procedure shunt from heart chamber to blood vessel atrium to pulmonary artery Fontan procedure left ventricle to aorta Rastelli procedure right ventricle to pulmonary artery Sano shunt compound procedures for transposition of the great vessels Arterial switch operation Mustard procedure Senning procedure for univentricular defect Norwood procedure Kawashima procedure shunt from blood vessel to blood vessel systemic circulation to pulmonary artery shunt Blalock—Taussig shunt SVC to the right PA Glenn procedure.
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Related Core Cardiology 12 lead ECG
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