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Einthoven
Willem Einthoven (21 May 1860 – 29 September 1927) was a Dutch doctor and physiologist. He invented the first practical electrocardiograph (ECG or EKG) in 1895 and received the Nobel Prize in Physiology or Medicine in 1924 for it ("for the discovery of the mechanism of the electrocardiogram"). original URL now redirects to https://ethw.org/Willem_Einthoven Background Willem Einthoven was born in Semarang on Java in the Dutch East Indies (now Indonesia), the son of Louise Marie Mathilde Caroline de Vogel and Jacob Einthoven. His father, a doctor, died when Willem was a child. His mother returned to the Netherlands with her children in 1870 and settled in Utrecht. His father was of Jewish and Dutch descent, and his mother's ancestry was Dutch and Swiss. In 1885, Einthoven received a medical degree from the University of Utrecht. He became a professor at the University of Leiden in 1886. He married his first cousin Frédérique Jeanne Louise de Vogel (7 September 1861 31 Januar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
String Galvanometer
A string galvanometer is a sensitive fast-responding measuring instrument that uses a single fine filament of wire suspended in a strong magnetic field to measure small currents. In use, a strong light source is used to illuminate the fine filament, and the optical system magnifies the movement of the filament allowing it to be observed or recorded by photography. The principle of the string galvanometer remained in use for electrocardiograms until the advent of electronic vacuum-tube amplifiers in the 1920s. History Submarine cable telegraph systems of the late 19th century used a galvanometer to detect pulses of electric current, which could be observed and transcribed into a message. The speed at which pulses could be detected by the galvanometer was limited by its mechanical inertia, and by the inductance of the multi-turn coil used in the instrument. Clément Adair, a French engineer, replaced the coil with a much faster wire or "string" producing the first string galvanome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrocardiography
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity. 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 (such as atrial fibrillation and ventricular tachycardia), inadequate coronary artery blood flow (such as myocardial ischemia and myocardial infarction), and electrolyte disturbances (such as hypokalemia and hyperkalemia). Traditionally, "ECG" usually means a 12-lead ECG taken while lying down as discussed below. However, other devices can record the electrical activity of the heart such as a Holter monitor but also s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Einthoven's Triangle
Einthoven's triangle is an imaginary formation of three limb leads in a triangle used in electrocardiography, formed by the two shoulders and the pubis. The shape forms an inverted equilateral triangle with the heart at the center. It is named after Willem Einthoven, who theorized its existence. Einthoven used these measuring points, by immersing the hands and foot in pails of salt water, as the contacts for his string galvanometer, the first practical ECG machine. Lead placements * Lead I — This axis goes from shoulder to shoulder, with the negative electrode placed on the right shoulder and the positive electrode placed on the left shoulder. This results in a 0 degree angle of orientation. : I = LA - RA * Lead II — This axis goes from the right arm to the left leg, with the negative electrode on the shoulder and the positive one on the leg. This results in a +60 degree angle of orientation. : II = LL - RA * Lead III — This axis goes from the left shoulder (negative el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Willem Thomas De Vogel
Willem Thomas de Vogel (26 March 1863 10 March 1955) was a colonial Dutch doctor and official who established the Department of Public Health in the Dutch East Indies (now Indonesia). Life Early life Willem Thomas de Vogel was born on 26 March 1863 in Toeban (now Tuban), Lasem (now Rembang), on Java in the Dutch East Indies. His father Henri Adrien Frédéric de Vogel (24 January 1825 17 August 1897) was Dutch but his mother Augusta Mary Stavers de Vogel (16 December 1840 4 January 1915) English; his sisters were Frances Maria Wilhelmina de Vogel Monod de Froideville (26 December 1859 4 March 1904), Frédérique Jeanne Louise de Vogel Einthoven (7 September 186131 January 1937), Augusta Henriette de Vogel (20 January 1866 8 December 1959), Rosetta Catherina Albertine de Vogel (16 January 1868 19 January 1949), and Catherine Elisabeth de Vogel Julius Roelants (4 July 1871 28 June 1959). He received his primary education from private tutors but went to Arnhem in the Netherlands for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
