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ECG
letters S through U
Term | Definition |
---|---|
Septum | Myocardial muscle fiber separating the right and left chambers of the heart |
Sink sinus syndrome | In the broadest sense, any abnormality in sinus node impulse formation or conduction |
Sinoatrial node( SA node) | Spread liked conductive myocardial cells located in the upper right atrium at the base of the superior vena cava, hearts natural pacemaker, 60-100 pm, establishes normal sinus cadence of the heart |
Sinus arrest | Prolonged failure of the SA node to initiate impulses. |
Sinus Arrhythmia | Increasing and decreasing heart rate affected by respiration so. Rates remain within normal limits but increase with inspiration and decrease with expiration |
Sinus block | Momentary cessation of sinus impulse formation. When P-P intervals are mapped out one complete cycle will have been dropped, with spontaneous resumption of cadence |
Sinus bradycardia | Slowing of the sinus node impulse firing causing the heart rate to fall below 60 bpm |
Sinus pause | Momentary cessation of sinus impulse formation. The pause occurs for less than one complete complex. Followed by spontaneous resumption of cadence |
Sinus rhythm | Any rhythm in which impulse formation originates within the SA node |
Sinus tachycardia | Rapid firing of the SA node impulse formation, causing the heart rate to increase to 100-159 bpm |
Supraventricular | Sites of impulse formation above the ventricles(sinus,Antrim,and AV node). The term is often used to refer to tachyarrhythmias when the exact origin of impulse formation is not distinguishable |
S wave | Negative deflection following R wave, component of ventricular depolarization |
Threshold | The minimal amount of stimulus required to prod us a. Response. In cardiac monitoring, the amount of electrical activity required to produced myocardial devil. May be from hearts own pacemaker or artifical pacemaker |
Titrate | Gradual reduction in administration of medication according to type and frequency of arrhythmias and condition of patient |
Trigeminy | Reoccurring pattern of cardiac contraction usually premature contractions in which every third complex in the pattern is abnormal |
T wave | Portion of the ECG that represents ventricular repolarization. Usually of the same deflection as the R wave |
Unifocal | Ectopic impulses that all originate from the same place within the myocardium. The resultant complexes will look all alike |
U wave | Low-voltage positive deflection immediately following ventricular repolarization T-wave. It's exact significance is still under investigation, but it is thought to have some relationship to the after potential of the ventricles |