Ecg In Psg Flashcards
Explain premature atrial contractions?
Extra beats precipitated by an electrical impulse to the atrium before the sinus node impulse. Characteristics include
an irregular pulse
QRS complex is usually normal
PR interval remains between 0.12 and 0.20. The p:qrs ratio is 1:1.
Not a concern unless they are frequent greater than six per hour & cause severe palpitations
Explain sinus arrhythmia?
Results from irregular impulses from the sinus node. Often increasing with inspiration and decreasing with expiration.
There is a regular pulse of 50 to 100 bpm.
Explain atrial flutter?
Atrial rate is faster (usually 250 to 400 beats a minute) then the atrioventricular node conduction rate
Atrial Flutter is characterized by atrial rate of 250 to 400 bpm with ventricular rates of 75 to 150 bpm
P waves saw toothed and referred to as f waves. The p-r interval maybe hard to calculate because f waves
P:qrs ratio is 2-4:1
Symptoms include chest pain dyspnea and hypotension.
What the normal values for P QRS ratio?
P to r interval?
QRS interval?
1: 1
0. 12-0.20 seconds
0. 04-0.11 seconds
Explain atrial fibrillation?
Characterized by a very irregular pulse with an atrial rate of 300 to 600 beats a minute and a Ventricular rate of 122- 200 beats per minute. The P to QRS ratio is highly variable.
Explain sinus pause?
When the sinus node fails to function properly to stimulate heart contractions and p wave.
Score asystole for pauses of more than three seconds for ages six through adulthood.
Explain premature junctional contractions?
Premature junctional contractions are similar to premature atrial contractions and generally require no treatment.
The electrocardiogram may appear basically normal with an early QRS complex that is normal in shape and duration
40/60bpm regular
Explain junctional rhythm?
They occur when the atrioventricular node becomes the pacemaker of the heart because the sinus node is depressed from increased Vagal tone, or a block at the AV node prevents SN impulses from being transmitted
40 to 60 bpm.
P:qrs ratio
Explain premature ventricular contractions?
The impulse begins in the ventricles and conducts through them before the next sinus impulse.
Explain ventricular tachycardia?
Three old more premature ventricular contractions in a row with a ventricular rate of 100 to 200 beats a minute.
Explain ventricular fibrillation?
Rapid very Irregular ventricular rate of more than 300 feet per minute with no atrial activity observable
Explain idioventricular rhythm rhythm rhythm or ventricular escape rhythm?
Purkinje fibers create an impulse.
Characterized by a regular ventricular rate of 20- 40 bpm.
QRS is bizarre with a duration of > 0.12secs
Explain first degree atrioventricular block?
This occurs when the atrial impulses are conducted through the Av node to the ventricles at a rate that is slower than normal.
Increased PR interval of 0.2 seconds on more.
Explain 2nd° atrioventricular block?
Type II and 2.1 block
Mobitz type 1 Each atrial impulse in a group of beats is conducted at a lengthened interval until one fails to conduct.
Mobitz type II Only some of the atrial impulses are conducted through the AV node to the ventricles. QRS ratio varies from 2:1, 3:1, 4:1.
The degree atrioventricular block?
Characterized by more P waves than QRS complexes with no Clear relationship between them
