Regularity: regular

Rate: 150 bpm

P Waves: none visible

PRI: none

QRS: 0.16 second

Interp: Ventricular

Tachycardia

9.130

Regularity: slightly irregular

Rate: approximately

75 bpm

P Waves: shape changes

from beat to beat

PRI: varies

QRS: 0.08 second

Interp: Wandering

Pacemaker

9.131

Regularity: regular

Rate: 71 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.32 second and

constant

QRS: 0.08 second

Interp: Sinus Rhythm with

First-Degree Heart Block

9.132

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: atrial rate 300 bpm;

ventricular rate 75 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.08 second in underlying rhythm (slightly

obscured by Flutter

waves); 0.16 second in

ectopic

Interp: Atrial Flutter with

4:1 response, with one

PVC

9.133

Regularity: regular

Rate: 83 bpm

P Waves: none

PRI: none

QRS: 0.08 second

Interp: Accelerated Junctional Rhythm

9.134

Regularity: irregular in

a pattern of grouped

beating

Rate: atrial rate 115 bpm;

ventricular rate approximately 70 bpm

P Waves: uniform; regular

P–P interval

PRI: varies; progressively

lengthens until one P

wave is not conducted

QRS: 0.10 second

Interp: Wenckebach (Type

I Second-Degree Heart

Block)

9.135

Regularity: regular underlying rhythm interrupted by

ectopics in a pattern of

grouped beating

Rate: approximately 70 bpm

P Waves: uniform; regular

P–P interval; no P wave

preceding ectopics

PRI: 0.16 second and

constant

QRS: 0.10 second in

underlying rhythm;

0.16 second in ectopics

Interp: Sinus Rhythm with

bigeminy of PVCs

9.136

Regularity: regular underlying rhythm interrupted by

ectopics in a pattern of

grouped beating

Rate: 79 bpm

P Waves: uniform in underlying rhythm; inverted

P waves following QRS

complexes of ectopics

PRI: 0.18 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.08 second in ectopics

Interp: Sinus Rhythm with

bigeminy of PJCs

9.137

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: 83 bpm

P Waves: uniform; regular

P–P interval; ectopic is

preceded by an upright

P wave

PRI: 0.16 second and

constant

QRS: 0.12 second in underlying rhythm; 0.12

second in ectopic

Interp: Sinus Rhythm (with

wide QRS) with one PAC

9.138

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 94 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.16 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.16 second in ectopics

Interp: Normal Sinus

Rhythm with bursts of

Ventricular Tachycardia

9.139

Regularity: regular

Rate: atrial rate 75 bpm;

ventricular rate 40 bpm

P Waves: uniform; regular

P–P interval

PRI: none

QRS: 0.08 second

Interp: Third-Degree Heart

Block (CHB)

9.140

Regularity: regular

Rate: 47 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.20 second and

constant

QRS: 0.08 second

Interp: Sinus Bradycardia

9.141

Regularity: regular

Rate: 125 bpm

P Waves: none visible

PRI: none

QRS: 0.20 second

Interp: slow Ventricular

Tachycardia

9.142

Regularity: regular

Rate: 94 bpm

P Waves: inverted preceding QRS complex

PRI: 0.12 second

QRS: 0.12 second

Interp: Accelerated Junctional Rhythm

9.143

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: approximately 80 bpm

P Waves: uniform in underlying rhythm; morphology changes with

ectopics

PRI: 0.14 second and

constant

QRS: 0.10 second in

underlying rhythm;

0.10 second in ectopics

Interp: Normal Sinus

Rhythm with three PACs

9.144

Answers Key 575

Regularity: regular

Rate: atrial rate 103 bpm;

ventricular rate 42 bpm

P Waves: uniform; regular

P–P interval

PRI: none

QRS: 0.16 second

Interp: Third-Degree Heart

Block (CHB) with ventricular escape focus

9.145

Regularity: irregular

Rate: atrial rate 300 bpm;

ventricular rate approximately 80 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.10 second

Interp: Atrial Flutter with

variable response

9.146

Regularity: regular

Rate: 83 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.32 second and

constant

QRS: 0.10 second

Interp: Sinus Rhythm with

First-Degree Heart Block

9.147

Regularity: regular

Rate: 38 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.16 second and

constant

QRS: 0.14 second

Interp: Sinus Bradycardia

(with wide QRS)

9.148

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: 115 bpm

P Waves: uniform; regular

P–P interval; no P wave

preceding ectopic

PRI: 0.16 second and

constant

QRS: 0.06 second in

underlying rhythm;

0.14 second in ectopic

Interp: Sinus Tachycardia

with one PVC

9.149

Regularity: slightly irregular

underlying rhythm interrupted by ectopic

Rate: approximately

55 bpm

P Waves: uniform in underlying rhythm; no P wave

preceding ectopic

PRI: 0.16 second

QRS: 0.08 second in

underlying rhythm;

0.12 second in ectopic

Interp: Sinus Bradycardia

with one PVC

9.150

Regularity: slightly irregular

Rate: approximately

250 bpm

P Waves: none visible

PRI: none

QRS: approximately

0.16 second

Interp: Ventricular

Tachycardia

9.151

Regularity: no visible

waves or complexes

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: none

Interp: Asystole

9.152

Regularity: irregular

Rate: approximately

150 bpm

P Waves: none visible

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

uncontrolled

9.153

Regularity: regular

Rate: 79 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.22 second and

constant

QRS: 0.10 second

Interp: Sinus Rhythm with

First-Degree Heart Block

9.154

Regularity: regular

Rate: 25 bpm

P Waves: none visible

PRI: none

QRS: 0.12 second

Interp: Idioventricular

Rhythm

9.155

Regularity: totally chaotic

baseline

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: unable to determine

Interp: Ventricular

Fibrillation

9.156

Regularity: regular

Rate: 100 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.14 second and

constant

QRS: 0.10 second

Interp: Sinus Tachycardia

9.157

Regularity: regular

Rate: 58 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.20 second and

constant

QRS: 0.08 second

Interp: Sinus Bradycardia

9.158

Regularity: totally chaotic

baseline

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: unable to determine

Interp: Ventricular

Fibrillation

9.159

Regularity: regular

Rate: 56 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.16 second and

constant

QRS: 0.08 second

Interp: Sinus Bradycardia

9.160

Regularity: regular

Rate: atrial rate 63 bpm;

ventricular rate 32 bpm

P Waves: uniform; regular P–P interval; more

P waves than QRS

complexes

PRI: none

QRS: 0.14 second

Interp: Third-Degree Heart

Block (CHB) with ventricular escape focus

9.161

Regularity: regular

Rate: 38 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.16 second and

constant

QRS: 0.10 second

Interp: Sinus Bradycardia

9.162

Regularity: regular

Rate: 79 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.20 second and

constant

QRS: 0.10 second

Interp: Normal Sinus

Rhythm

9.163

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: 63 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopic

PRI: 0.20 second and

constant

QRS: 0.14 second in

underlying rhythm;

0.16 second in ectopic

Interp: Sinus Rhythm (with

wide QRS) with one PVC

9.164

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 63 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.24 second and

constant

QRS: 0.10 second in

underlying rhythm;

0.16 second in ectopics

Interp: Sinus Rhythm with

First-Degree Heart Block

with two unifocal PVCs

9.165

576 Answers Key

Regularity: irregular

Rate: approximately

110 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.06 second

Interp: Atrial Fibrillation,

uncontrolled

9.166

Regularity: irregular

Rate: atrial rate 300 bpm;

ventricular rate approximately 100 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.10 second

Interp: Atrial Flutter with

variable response

9.167

Regularity: regular

Rate: 107 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.14 second and

constant

QRS: 0.06 second

Interp: Sinus Tachycardia

9.168

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 103 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.14 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Sinus Tachycardia

with two PVCs and coupled PVCs, all unifocal

9.169

Regularity: regular underlying rhythm interrupted

by ectopics in a pattern

of grouped beating

Rate: visible sinus rate is

36 bpm; actual sinus

rate is probably 72 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.16 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.16 second in ectopics

Interp: Sinus Rhythm with

bigeminy of PVCs

9.170

Regularity: totally chaotic

baseline

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: unable to determine

Interp: Ventricular Fibrillation (Agonal Rhythm)

9.171

Regularity: regular

Rate: atrial rate 96 bpm;

ventricular rate 48 bpm

P Waves: uniform; regular P–P interval; two P

waves for every QRS

complex

PRI: 0.20 second and

constant on conducted

beats

QRS: 0.10 second

Interp: Type II SecondDegree Heart Block (2:1)

9.172

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 68 bpm

P Waves: uniform in underlying rhythm; morphology changes in ectopics

PRI: 0.20 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.10 second in ectopics

Interp: Normal Sinus

Rhythm with two PACs

9.173

Regularity: irregular

Rate: atrial rate 333 bpm;

ventricular rate approximately 70 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.08 second

Interp: Atrial Flutter with

variable response

9.174

Regularity: regular underlying rhythm interrupted by

ectopics in a pattern of

grouped beating

Rate: 83 bpm

P Waves: uniform in underlying rhythm; morphology changes in ectopics

PRI: 0.12 second and

constant

QRS: 0.10 second in

underlying rhythm;

0.10 second in ectopics

Interp: Sinus Rhythm with

trigeminy of PACs

9.175

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 75 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.20 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.12 second in ectopics

Interp: Normal Sinus

Rhythm with two unifocal PVCs

9.176

Regularity: regular

Rate: 60 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.24 second and

constant

QRS: 0.08 second

Interp: Sinus Rhythm with

First-Degree Heart Block

9.177

Regularity: irregular

Rate: approximately

80 bpm

P Waves: morphology

changes with each beat

PRI: varies

QRS: 0.12 second

Interp: Wandering Pacemaker (with wide QRS)

9.178

Regularity: regular underlying rhythm interrupted

by ectopics in a pattern

of grouped beating

Rate: approximately

80 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.14 second and

constant in underlying

rhythm

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Sinus Rhythm with

bigeminy of PVCs

9.179

Regularity: regular

Rate: 115 bpm

P Waves: none visible

PRI: none

QRS: 0.08 second

Interp: Junctional

Tachycardia

9.180

Regularity: irregular in

a pattern of grouped

beating

Rate: atrial rate 88 bpm;

ventricular rate approximately 60 bpm

P Waves: uniform; regular

P–P interval; some P

waves are not followed

by QRS complexes

PRI: varies; progressively

lengthens until a beat is

not conducted

QRS: 0.10 second

Interp: Wenckebach (Type

I Second-Degree Heart

Block)

9.181

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 107 bpm

P Waves: uniform in underlying rhythm; no P wave

preceding ectopics

PRI: 0.12 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Sinus Tachycardia

with PVC and coupled

PVCs, all unifocal

9.182

Answers Key 577

Regularity: no visible

complexes; essentially

straight line

Rate: not discernible

P Waves: none

PRI: none

QRS: none

Interp: Asystole (Agonal

Rhythm)

9.183

Regularity: slightly irregular

Rate: approximately

70 bpm

P Waves: morphology

changes from beat to

beat

PRI: varies slightly

(0.18–0.20 second)

QRS: 0.08 second

Interp: Wandering

Pacemaker

9.184

Regularity: regular underlying rhythm interrupted

by ectopics in a pattern

of grouped beating

Rate: 120 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.12 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.12 second in ectopics

Interp: Sinus Tachycardia

with bigeminy of PVCs

9.185

Regularity: regular

Rate: 54 bpm

P Waves: inverted in front

of QRS complexes

PRI: 0.12 second and

constant

QRS: 0.08 second

Interp: Junctional Escape

Rhythm

9.186

Regularity: regular

Rate: atrial rate 100 bpm;

ventricular rate 35 bpm

P Waves: uniform; regular P–P interval; more

P waves than QRS

complexes

PRI: none

QRS: 0.20 second

Interp: Third-Degree Heart

Block (CHB) with ventricular escape focus

9.187

Regularity: irregular

Rate: approximately

100 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

controlled

9.188

Regularity: totally chaotic

baseline

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: none

Interp: Ventricular

Fibrillation

9.189

Regularity: irregular

Rate: approximately

90 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

controlled

9.190

Regularity: irregular

Rate: approximately

80 bpm

P Waves: none discernible;

undulations present

PRI: none

QRS: 0.16 second

Interp: Atrial Fibrillation,

controlled (with wide

QRS)

9.191

Regularity: regular underlying rhythm interrupted

by ectopics in a pattern

of grouped beating

Rate: 100 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.14 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Sinus Tachycardia

with trigeminy of PVCs

9.192

Regularity: slightly irregular

Rate: approximately

136 bpm

P Waves: none visible

PRI: none

QRS: 0.16 second

Interp: Ventricular Tachycardia (slow rate range)

9.193

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 83 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.16 second and

constant

QRS: 0.12 second in

underlying rhythm;

0.16 second in ectopics

Interp: Sinus Rhythm (with

wide QRS) with two unifocal PVCs

9.194

Regularity: regular

Rate: atrial rate 125 bpm;

ventricular rate 22 bpm

P Waves: uniform; regular

P–P interval

PRI: none

QRS: 0.12 second

Interp: Third-Degree Heart

Block (CHB) with ventricular escape focus

9.195

Note: You might also want to note that the atria are being

depolarized at a faster than normal rate. You could call

this a CHB with an underlying Sinus Tachycardia.

Regularity: regular

Rate: 125 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.16 second and

constant

QRS: 0.10 second

Interp: Sinus Tachycardia

9.196

Regularity: regular

Rate: 94 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.24 second and

constant

QRS: 0.10 second

Interp: Sinus Rhythm with

First-Degree Heart Block

9.197

Regularity: regular

Rate: atrial rate 264 bpm;

ventricular rate 88 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.12 second

Interp: Atrial Flutter with

3:1 response

9.198

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: 71 bpm

P Waves: uniform; regular

P–P interval; no P wave

preceding ectopic

PRI: 0.16 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopic

Interp: Normal Sinus

Rhythm with one PVC

9.199

Regularity: regular

Rate: 167 bpm

P Waves: none visible

PRI: none

QRS: 0.16 second

Interp: Ventricular

Tachycardia

9.200

Regularity: totally chaotic

baseline

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: none

Interp: Ventricular Fibrillation (Agonal Rhythm)

9.201

Regularity: regular

Rate: approximately

48 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.20 second and

constant

QRS: 0.10 second

Interp: Sinus Bradycardia

9.202

578 Answers Key

Regularity: regular underlying rhythm interrupted

by frequent ectopics

Rate: 107 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.12 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Sinus Tachycardia

with three PVCs, two of

them coupled

9.203

Regularity: regular

Rate: 115 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.14 second and

constant

QRS: 0.08 second

Interp: Sinus Tachycardia

9.204

Regularity: irregular

Rate: approximately

100 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

controlled

9.205

Regularity: regular

Rate: 43 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.20 second and

constant

QRS: 0.06 second

Interp: Sinus Bradycardia

9.206

Regularity: irregular

Rate: approximately 60 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

controlled

9.207

Regularity: regular underlying rhythm interrupted

by ectopics

Rate: 94 bpm

P Waves: uniform in underlying rhythm; no P waves

preceding ectopics

PRI: 0.16 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.14 second in ectopics

Interp: Normal Sinus

Rhythm with two unifocal PVCs

9.208

Regularity: regular

Rate: 143 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.14 second and

constant

QRS: 0.08 second

Interp: Sinus Tachycardia

9.209

Regularity: regular

Rate: 47 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.28 second and

constant

QRS: 0.10 second

Interp: Sinus Bradycardia

with First-Degree Heart

Block

9.210

Regularity: irregular

Rate: approximately

150 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.12 second

Interp: Atrial Fibrillation,

uncontrolled (with wide

QRS)

9.211

Regularity: irregular initially,

then totally chaotic

Rate: unable to determine

P Waves: none visible

PRI: none

QRS: approximately

0.16 second in initial

rhythm; unable to measure in terminal pattern

Interp: Ventricular Tachycardia into Ventricular

Fibrillation

9.212

Regularity: irregular

Rate: approximately

130 bpm

P Waves: none visible; undulations present

PRI: unable to determine

QRS: 0.10 second

Interp: Atrial Fibrillation,

uncontrolled

9.213

Regularity: regular underlying rhythm interrupted

by ectopic

Rate: 84 bpm

P Waves: uniform in underlying rhythm; no P wave

preceding ectopic

PRI: 0.24 second and

constant

QRS: 0.08 second in

underlying rhythm;

0.12 second in ectopic

Interp: Sinus Rhythm with

First-Degree Heart Block

with one PVC

9.214

Regularity: irregular

Rate: approximately

110 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.08 second

Interp: Atrial Fibrillation,

uncontrolled

9.215

Regularity: irregular

Rate: atrial rate 250 bpm;

ventricular rate 70 bpm

P Waves: characteristic

sawtooth pattern

PRI: unable to determine

QRS: 0.08 second

Interp: Atrial Flutter with

variable response

9.216

Regularity: regular

Rate: 125 bpm

P Waves: uniform; regular

P–P interval

PRI: 0.16 second and

constant

QRS: 0.14 second

Interp: Sinus Tachycardia

(with wide QRS)

9.217

Regularity: regular

Rate: atrial rate 167 bpm;

ventricular rate 22 bpm

P Waves: uniform; regular

P–P interval

PRI: none

QRS: 0.14 second

Interp: Third-Degree Heart

Block (CHB) with ventricular escape focus

9.218

Note: You might also want to note that the atria are being depolarized at a faster than normal rate. You could

call this a CHB with an underlying Atrial Tachycardia.

Regularity: regular

Rate: 167 bpm

P Waves: none visible

PRI: unable to determine

QRS: 0.08 second

Interp: Supraventricular

Tachycardia

9.219

Regularity: irregular

Rate: approximately

120 bpm

P Waves: none visible; undulations present

PRI: none

QRS: 0.10 second

Interp: Atrial Fibrillation,

uncontrolled

9.220

Regularity: regular

Rate: 60 bpm

P Waves: uniform and

upright

PRI: 0.22 second and

constant

QRS: 0.08 second

Interp: Sinus Bradycardia

with First-Degree Heart

Block

9.221