ArrhythmiasThe normal EKG consists of repetitive series of P, Q, R, S, and T Waves, which conform to established standards for size and shape and occur 60 – 100 times each minute. If these conditions prevail, the heart is in normal sinus rhythm. When either the rate of the contour of any of the individual waves is abnormal, the disorder is called an arrhythmia. Classifications of Arrhythmias: There are several ways in which arrhythmias may be classified. Perhaps the most logical method involves classification, first, by the site of the arrhythmia and secondly by the type of mechanism responsible for the disorder.
Arrhythmias can also be classified in a general way according to their seriousness or prognosis. This is a meaningful method for nurses caring for patients with acute Myocardial Infarction and the one we have found useful. Using this division, arrhythmias may be considered as:
Identifying ECG Features – Sinus Arrhythmias
The heart rate per minute is normal (60-100); however, the rate increased during inspiration and then slows during expiration.
Sinus Arrhythmia:
Sinus Bradycardia Sinus Bradycardia is an arrhythmia defined as a rate below 60 BPM with all beats remaining normal. The SA node is still the pacemaker and the conduction pathway is still normal. This rhythm can be normal during sleep, for athletes, for persons on certain medications and other reasons. It can be an abnormal rhythm in certain conditions such as myocardial infarction or congestive heart failure, or if the rate falls so low as to cause clinical symptoms such as fainting of dizziness, etc. Sinus Bradycardia Indentifying ECG Features
Example Sinus Bradycardia
Sinus Tachycardia Sinus tachycardia is another sinus arrhythmia. Causes of this condition are exercise, anxiety, fear, fever, and others. If the tachycardia is secondary to another factor, such as above, usually no treatment is needed, as these conditions are usually temporary. However, if clinical signs are seen, such as dizziness, fainting, or others, treatment may be indicated and perhaps more than just simple sinus tachycardia is present.
Example: Sinus Tachycardia
Example 2 Sinus Tachycardia Next: Part II: Abnormal Rhythms |