Search results
Results from the WOW.Com Content Network
Failure of a pacemaker is defined by the requirement of repeat surgical pacemaker-related procedures after the initial implantation. Most implanted pacemakers are dual chambered and have two leads, causing the implantation time to take longer because of this more complicated pacemaker system.
An artificial cardiac pacemaker (or artificial pacemaker, so as not to be confused with the natural cardiac pacemaker) or just pacemaker is an implanted medical device that generates electrical impulses delivered by electrodes to the chambers of the heart either the upper atria, or lower ventricles to cause the targeted chambers to contract and ...
The pacemaker generator is a hermetically sealed device containing a power source, usually a lithium battery, a sensing amplifier which processes the electrical manifestation of naturally occurring heart beats as sensed by the heart electrodes, the computer logic for the pacemaker and the output circuitry which delivers the pacing impulse to ...
This condition can be detected on an electrocardiogram (ECG) as a brief period of irregular length with no electrical activity before either the sinoatrial node resumes normal pacing, or another pacemaker begins pacing. If a pacemaker other than the sinoatrial node is pacing the heart, this condition is known as an escape rhythm.
Twiddler's syndrome is a malfunction of a pacemaker due to manipulation of the device and the consequent dislodging of the leads from their intended location. As the leads move, they stop pacing the heart and can cause strange symptoms such as phrenic nerve stimulation resulting in abdominal pulsing or brachial plexus stimulation resulting in rhythmic arm twitching. [1]
The AV node normally has the second fastest discharge rate. When the sinus rate falls below the discharge rate of the AV node, this becomes the dominant pacemaker, and the result is called a junctional escape beat. If the rate from both the SA and AV node fall below the discharge rate of ventricular pacemaker cells, a ventricular escape beat ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Once the pacemaker potential reaches a set value, the threshold potential, it produces an action potential. [2] Other cells within the heart (including the Purkinje fibers [ 11 ] and atrioventricular node ) can also initiate action potentials; however, they do so at a slower rate and therefore, if the SA node is functioning properly, its action ...