Search results
Results from the WOW.Com Content Network
The sinoatrial node (SA node) is the primary pacemaker of the heart. It is a region of cardiac muscle on the wall of the upper right atrium near to the superior vena cava entrance. The cells that make up the SA node are specialized cardiomyocytes known as pacemaker cells that can spontaneously generate cardiac action potentials.
Sinus node dysfunction (SND), also known as sick sinus syndrome (SSS), is a group of abnormal heart rhythms (arrhythmias) usually caused by a malfunction of the sinus node, the heart's primary pacemaker. [1] [2] Tachycardia-bradycardia syndrome is a variant of sick sinus syndrome in which the arrhythmia alternates between fast and slow heart ...
The primary purpose of a pacemaker is to maintain an even heart rate, either because the heart's natural cardiac pacemaker provides an inadequate or irregular heartbeat, or because there is a block in the heart's electrical conduction system. Modern pacemakers are externally programmable and allow a cardiologist to select the optimal pacing ...
Cardiac pacemaker; Cardiac Pacemakers, Inc. Cardiac resynchronization therapy; Cardiac rhythmicity; Cardiac transient outward potassium current; Cardiovascular technologist; Clinical cardiac electrophysiology; Concealed conduction; Ross Cowie
This page was last edited on 2 January 2015, at 22:11 (UTC).; Text is available under the Creative Commons Attribution-ShareAlike 4.0 License; additional terms may ...
A premature ventricular contraction (PVC) is a common event where the heartbeat is initiated by Purkinje fibers in the ventricles rather than by the sinoatrial node.PVCs may cause no symptoms or may be perceived as a "skipped beat" or felt as palpitations in the chest.
The approach to primary prevention promotes a healthy diet, exercise, limited alcohol consumption, and smoking cessation. [ 5 ] Exercise is an effective preventative measure for cardiac arrest in the general population but may be risky for those with pre-existing conditions. [ 71 ]
Artificial pacemakers may be used in patients with intraventricular conduction delay, and implantable cardioverter-defibrillators in those at risk of arrhythmia. These forms of treatment have been shown to prevent sudden cardiac death, improve symptoms, and reduce hospitalization in patients with systolic heart failure. [ 37 ]