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Second Degree Heart Block Type I ECG Interpretation with Sample Strip

ECG Strip

ecg rhythm strip for reference guide

Second Degree Heart Block Type I Rhythm Strip Features

Rate: The underlying rate
Rhythm: Irregular but with progressively longer PR interval lengthening
P Wave: Normal
PR Interval: Progressively longer until a QRS complex is missed, then cycle repeats
QRS: Normal (0.06-0.10 sec)
A prolonging P-R interval from one cardiac complex to the next, until it reaches a point where the QRS complex is non-conducted (blocked or more simply missing). Then the pattern starts over again.
Second degree Heart Block Type I Wenckebach is a condition where the atrioventricular node conducts each successive impulse earlier and earlier. The PQ interval prolongs from beat to beat up until a drop-out of one QRS complex. The following impulse will then be conducted normally and the cycle to begin again. Thus, the presence of second-degree AV block is diagnosed when one or more (but not all) of the atrial impulses fail to conduct to the ventricles.
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? v:4 | onAr:0 | onPs:2 | tLb:0 | pv:1
uStat: False | db:0 | cc: US | tar: False
| cDbLookup # 0 | pu: False | pl: System.Collections.Generic.List`1[System.String]
em: | newuser: False

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