Search results
Results From The WOW.Com Content Network
Commotio cordis can occur only upon impact within a narrow window of about 40 milliseconds in the cardiac electrical cycle, explaining why it is so rare. [ 1 ] If cardiopulmonary resuscitation (CPR) combined with the use of an on-site automated external defibrillator is employed within three minutes of the impact, survival from commotio cordis ...
Defibrillation is often an important step in cardiopulmonary resuscitation (CPR). [6] [7] CPR is an algorithm-based intervention aimed to restore cardiac and pulmonary function. [6] Defibrillation is indicated only in certain types of cardiac dysrhythmias, specifically ventricular fibrillation (VF) and pulseless ventricular tachycardia.
The action potential passes along the cell membrane causing the cell to contract, therefore the activity of the sinoatrial node results in a resting heart rate of roughly 60–100 beats per minute. All cardiac muscle cells are electrically linked to one another, by intercalated discs which allow the action potential to pass from one cell to the ...
Ectopic beat is a disturbance of the cardiac rhythm frequently related to the electrical conduction system of the heart, in which beats arise from fibers or group of fibers outside the region in the heart muscle ordinarily responsible for impulse formation (i.e., the sinoatrial node).
Rhythm interpretation is an important part of healthcare in Emergency Medical Services . Trained medical personnel can determine different treatment options based on the cardiac rhythm of a patient. There are many common heart rhythms that are part of a few different categories, sinus arrhythmia, atrial arrhythmia, ventricular arrhythmia.
Junctional rhythms (if a bradycardia) can cause decreased cardiac output. Therefore, the person may exhibit signs and symptoms similar to other bradycardia such as lightheadedness, dizziness, low blood pressure, and fainting. This rhythm can usually be tolerated if the rate is above 50 beats per minute. [citation needed]
The conduction system consists of specialized heart muscle cells, situated within the myocardium. [3] There is a skeleton of fibrous tissue that surrounds the conduction system which can be seen on an ECG. Dysfunction of the conduction system can cause irregular heart rhythms including rhythms that are too fast or too slow.
The uncontrolled wave of calcium can be forced out through the cell membrane via the sodium-calcium exchanger, causing an electric current known as a delayed afterdepolarisation. Afterdepolarisations, if large enough, can trigger additional action potentials, premature ventricular contractions, or sustained arrhythmias. [15]