Cardiac electrophysiology

middle layer of the heart wall, which consists of cardiac muscle

thumb|Use of monitoring (medicine)|real time monitoring of the heart in an [[intensive care unit in a German hospital (2015), the monitoring screen above the patient displaying an electrocardiogram and various values of parameters of the heart like heart rate and blood pressure]]

A pacemaker, also known as an artificial cardiac pacemaker, is an implanted medical device that generates electrical pulses delivered by electrodes to one or more of the chambers of the heart. Each pulse causes the targeted chamber(s) to contract and pump blood, thus regulating the function of the electrical conduction system of the heart.

Defibrillation is a treatment for life-threatening cardiac arrhythmias, specifically ventricular fibrillation (V-Fib) and non-perfusing ventricular tachycardia (V-Tach). Defibrillation delivers a dose of electric current (often called a counter-shock) to the heart. Although not fully understood, this process depolarizes a large amount of the heart muscle, ending the arrhythmia. 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 defibrillation; it would be trea

portable electronic device that automatically diagnoses the life-threatening cardiac arrhythmias of ventricular fibrillation and pulseless ventricular tachycardia in a patient

transmits signals generated usually by the sinoatrial node to cause contraction of the heart muscle

pharmaceutical used to suppress abnormal rhythms of the heart

fibers that allow the heart's conduction system to create synchronized contractions of its ventricles

collection of heart muscle cells specialized for electrical conduction

device implantable inside the body, able to perform cardioversion, defibrillation, and (in modern versions) pacing of the heart

measure of the time between the start of the Q wave and the end of the T wave in the heart's electrical cycle

Network of cells that facilitate rhythmic heart contraction

in physiology

defect of the bundle branches or fascicles in the electrical conduction system of the heart

the ST segment connects the QRS complex and the T wave and has a duration of 0.080 to 0.120 sec

combination of three of the graphical deflections seen on a typical electrocardiogram

represents atrial depolarization, which results in atrial contraction

the period, measured in milliseconds, that extends from the beginning of the P wave (the onset of atrial depolarization) until the beginning of the QRS complex (the onset of ventricular depolarization)

biological process in the heart

represents the repolarization (or recovery) of the ventricles

Mathematical model of a dendrite

in a biological membrane

ECG waveform thought to represent repolarization of the Purkinje fibers

medical diagnostic method

irregular heart rate caused by abnormal function of the sinoatrial node

ILR

concept in electrocardiography

Potassium voltage-gated channel subfamily KQT member 1 is a potassium channel protein encoded in the human by the KCNQ1 gene. Its mutation causes long QT syndrome, Kv7.1 is a voltage and lipid-gated potassium channel present in the cell membranes of cardiac tissue and in inner ear neurons among other tissues. In the cardiac cells, Kv7.1 mediates the IKs (or slow delayed rectifying K+) current that contributes to the repolarization of the cell, terminating the cardiac action potential and thereby the heart's contraction. It is a member of the KCNQ family of potassium channels.

treatment for heart failure

Ballistocardiography (BCG) is the measurement of ballistic forces generated by the heart. The downward movement of blood through the descending aorta produces an upward recoil, moving the body upward with each heartbeat. As different parts of the aorta expand and contract, the body continues to move downward and upward in a repeating pattern. Ballistocardiography is a technique for producing a graphical representation of repetitive motions of the human body arising from the sudden ejection of blood into the great vessels with each heart beat. It is a vital sign in the 1–20 Hz frequency range w

implantable medical device

medical intervention

Medical test.

Afterdepolarizations are abnormal depolarizations of cardiac myocytes that interrupt phase 2, phase 3, or phase 4 of the cardiac action potential in the electrical conduction system of the heart. Afterdepolarizations may lead to cardiac arrhythmias. Afterdepolarization is commonly a consequence of myocardial infarction, cardiac hypertrophy, or heart failure. It may also result from congenital mutations associated with calcium channels and sequestration.

science of elucidating, diagnosing and treating the electrical activities of the heart