Late potentials

From ECGpedia
Jump to navigation Jump to search

Late potentials are thought to be caused by early afterdepolarizations of cells in the right ventricle (in ARVD). Their amplitude is often too small to show up on a normal ECG. However, when multiple QRS recordings (typically 250 consecutive QRS complexes) are averaged, random noise is filtered out and late potentials can show up. Such a recording is called a Signal Averaged ECG (SAECG). The ARVD taskforce has published a document with recommended settings to record an SAECG in ARVD.

Late potentials.png
Criteria for late potentials on a signal averaged ECG [1][2]
  • filtered QRS duration > 114ms
  • terminal (last 40ms) QRS root means square (RMS) voltage < 20 µV
  • low amplitude (<40 µV) signal (LAS) duration > 38ms
  • Noise should be minimal with a standard deviation of the TP segment of < 1 µV

References

  1. Simson MB. Use of signals in the terminal QRS complex to identify patients with ventricular tachycardia after myocardial infarction. Circulation. 1981 Aug;64(2):235-42. DOI:10.1161/01.cir.64.2.235 | PubMed ID:7249291 | HubMed [simson]
  2. Breithardt G, Cain ME, el-Sherif N, Flowers NC, Hombach V, Janse M, Simson MB, and Steinbeck G. Standards for analysis of ventricular late potentials using high-resolution or signal-averaged electrocardiography: a statement by a task force committee of the European Society of Cardiology, the American Heart Association, and the American College of Cardiology. J Am Coll Cardiol. 1991 Apr;17(5):999-1006. DOI:10.1016/0735-1097(91)90822-q | PubMed ID:2007727 | HubMed [Breithardt]

All Medline abstracts: PubMed | HubMed