#1
Rate: 33
Rhythm: Irregular
P Waves: Present
PRI: 0.22 to 0.36
QRS: 0.10
Intrp: Second-degree, Type 1 AV block (Wenckebach)

#2
Rate: 107
Rhythm: Irregular
P Waves: Present for most beats
PRI: 0.16
QRS: 0.09 to 0.10
Intrp: Normal sinus rhythm with premature junctional contractions (fifth, eighth, ninth, and tenth QRS complexes) occurring singly and in group beats; the latter may be considered a short episode of paroxysmal junctional tachycardia.

#3
Rate: Unmeasurable
Rhythm: Irregular
P Waves: None
PRI: None
QRS: None
Intrp: Ventricular fibrillation (coarse)

#4
Rate: 61
Rhythm: Irregular
P Waves: Present
PRI: 0.12
QRS: 0.14
Intrp: Sinus arrhythmia with bundle branch block

#5
Rate: 89
Rhythm: Irregular
P Waves: Present except the second and eighth QRS complexes
PRI: 0.18
QRS: 0.08
Intrp: Normal sinus rhythm with isolated unifocal premature ventricular contractions

#6
Rate: 87
Rhythm: Irregular
P Waves: Present
PRI: 0.18
QRS: 0.05
Intrp: Sinus arrhythmia

#7
Rate: 74
Rhythm: Regular
P Waves: shape and direction vary
PRI: 0.08 to 0.12
QRS: 0.08
Intrp: Wandering atrial pacemaker

#8
Rate: 83
Rhythm: Regular
P Waves: Present
PRI: 0.16
QRS: 0.06
Intrp: Normal sinus rhythm

#9
Rate: 229
Rhythm: Regular
P Waves: None
PRI: None
QRS: 0.12
Intrp: Ventricular tachycardia

#10
Rate: 26
Rhythm: Regular
P Waves: Present
PRI: 0.19
QRS: 0.10
Intrp: Sinus rhythm with second-degree 2:1 AV block (classical)

#11
Rate: 84
Rhythm: Regular
P Waves: None
PRI: None
QRS: 0.08
Intrp: Atrial flutter

#12
Rate: 30
Rhythm: Regular
P Waves: Present
PRI: 0.17 to 0.18
QRS: 0.12
Intrp: Sinus bradycardia with bundle branch block

#13
Rate: 62
Rhythm: Irregular
P Waves: Present
PRI: 0.18
QRS: 0.12
Intrp: Normal sinus rhythm with bundle branch block and premature junctional contractions.

#14
Rate: 31
Rhythm: Irregular
P Waves: Present
PRI: 0.34
QRS: 0.16
Intrp: Sinus rhythm with second-degree, high degree AV block and bundle branch block

#15
Rate: 41
Rhythm: Irregular
P Waves: Present
PRI: 0.14
QRS: 0.12
Intrp: Sinus rhythm with sinoatrial block, first-degree AV block, bundle branch block, and
an isolated junctional escape beat (third QRS complex)

#16
Rate: 17
Rhythm: Undeterminable
P Waves: None
PRI: None
QRS: 0.14
Intrp: Ventricular escape rhythm

#17
Rate: 70
Rhythm: Regular
P Waves: Present
PRI: 0.16
QRS: 0.06
Intrp: Normal sinus rhythm

#18
Rate: 52
Rhythm: Regular
P Waves: Present
PRI: 0.20
QRS: 0.06
Intrp: Normal sinus rhythm