SINOAURICULAR LOCK. It is the sinus pause (without P waves) of duration equal to twice the normal sinus cycle. Sinoatrial block is due to a conduction disorder during which an impulse from the sinus node cannot depolarize or is delayed.
Summary
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- 1 Diagnosis
- 2 Etiology
- 3 1st degree Sinoauricular Block
- 4 2nd degree Sinoauricular block type II
- 5 3rd degree Sinoauricular Block
- 6 2nd degree Sinoauricular block type I
- 7 See also
- 8 External Links
- 9 Sources
Diagnosis
Interruption of the sinus rhythm due to a pause or lengthening of the PP interval equal to twice a normal cycle.
Etiology
Similar to the one described for Sinus arrest .
1st degree Sinoauricular block
They cannot be recognized on a normal EKG.
2nd degree Sinoauricular block type II
An interval without P waves that is equivalent to approximately 2, 3 or 4 times the normal PP cycle.
3rd degree Sinoauricular block
It can be recorded as the absence of P waves but cannot be confirmed without recording an ECG of the previous sinus rhythm.
2nd degree Sinoauricular block type I
Progressive shortening of the PP interval until a longer PP interval appears (containing the blocked pulse). The longest PP interval is less than the sum of two consecutive intervals.