ECG of the Week - 10th December 2018 - Interpretation

The following ECG is from an 80 yr old male who presented with chest pain.

 

 

 

Click to enlarge

Rate:

• 84 bpm

Rhythm:

• Regular
• Sinus rhythm - P waves best seen in leads V2-3

Axis:

• Normal

Intervals:

• QRS - Normal

Additional:

• Significant baseline artefact
• ST elevation leads V1-3

Interpretation:

• Baseline artefact
• Secondary to pre-existing Parkinson's disease

 Troubleshooting artefact

  There are multiple factors that can generate artifact during the ECG recording / printing process including:

 

• Patient factors
• Implanted devices
• PPM - Pacing Spikes
• Nerve stimulators
• Movement disorders e.g. Parkinson's, essential tremor
• Rigors
• Muscle tremor / activity can be related to pain, hypothermia etc.
• CPR
• Habitus - very thin or obese patients, paediatric patients
• Poor pad contact due to hair
• Poor pad contact due to moisture - sweating, immersion etc.
• Lead factors
• Poor pad contact
• Pad misplacement
• Damaged lead or lead connection
• ECG Machine Factors
• Inappropriate settings of gain or filtering modes
• Electrical artifact from power supply
• Printing factors
• Low ink
• Print head tracking
• Paper alignment
• External factors
• Interference from surrounding electronic devices. Relatively rare using newer ECG machines and environmental interference is usually compounded by incorrect machine filter settings.

An awareness of these factors and a systemic approach to addressing each point in the recording process, from patient to printer, is important in addressing recording problems such as artifact and lead mal-positioning.

 

References / Further Reading

Textbook

• Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.