PSG Tech Guide

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Cardiac / EKG

Common EKG rhythms

Recognize normal rhythm and common arrhythmias seen during studies.

Educational reference, not a diagnostic tool. A scored event, an elevated index and a clinical diagnosis are different things. Follow your facility’s scoring manual, notification policies and clinical protocols.

  • Know your lab's notification criteria.
  • Single-lead EKG has limits — escalate uncertain rhythms.
  • These short teaching strips illustrate rhythm recognition, not PSG scoring-duration requirements. Confirm sustained duration separately against your facility’s current scoring manual.

Waveforms

Normal sinus rhythm

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformRegular R–R intervals; a similar P wave precedes each narrow QRS.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: AHA (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Sinus bradycardia

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformSlow, regular rhythm; P waves precede the narrow QRS complexes.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: AHA (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Sinus tachycardia

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformFast, regular rhythm with a consistent P wave before each QRS.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: Tachycardia (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Atrial fibrillation / AFib

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformR–R intervals vary without a repeating pattern.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: AF (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Atrial flutter

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformOrganized sawtooth atrial activity continues between QRS complexes.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: Flutter (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Premature ventricular contraction / PVC

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformThe highlighted beat is premature and wide, with no associated preceding P wave.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: PVC (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Premature atrial contraction / PAC

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformThe early P wave has a different shape; its conducted QRS remains narrow here.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: PAC (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Ventricular bigeminy

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformEach normal sinus beat is followed by a premature wide ventricular beat.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: PVC (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Regular narrow-complex tachycardia

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformRapid regular narrow QRS complexes; separate P waves are not apparent here.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: Tachycardia (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Monomorphic wide-complex tachycardia

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformRapid, repeating broad complexes with similar shape.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: Tachycardia, Safety (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Ventricular fibrillation / VF

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformChaotic activity without identifiable organized ventricular complexes.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: VF, Safety (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Artifact over an underlying sinus rhythm

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformRegular underlying QRS timing continues through the interference in this example.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: Safety (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

Apparent cardiac pause

Not clinically reviewed

Cardiac / EKG

Illustrative teaching waveformA prolonged R–R gap is shown; absent P waves are also modeled during the gap.Source: Original synthetic teaching waveform. Relative amplitude, not calibrated mV. Not patient data. Printed source reference: AHA, Safety (see guide). Full source details were not supplied or verified.Rhythm recognition example only, not a complete diagnosis or PSG scoring rule. Confirm PSG scoring-duration requirements separately using your facility’s current scoring manual. Not AASM-approved.

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EKG