请输入您要查询的百科知识:

 

词条 ST segment
释义

  1. Interpretation

  2. In fetal monitoring

  3. References

In electrocardiography, the ST segment connects the QRS complex and the T wave and has a duration of 0.005 to 0.150 sec (5 to 150 ms).

It starts at the J point (junction between the QRS complex and ST segment) and ends at the beginning of the T wave. However, since it is usually difficult to determine exactly where the ST segment ends and the T wave begins, the relationship between the ST segment and T wave should be examined together. The typical ST segment duration is usually around 0.08 sec (80 ms). It should be essentially level with the PR and TP segments.

The ST segment represents the isoelectric period when the ventricles are in between depolarization and repolarization.

Interpretation

  • The normal ST segment has a slight upward concavity.
  • Flat, downsloping, or depressed ST segments may indicate coronary ischemia.
  • ST elevation may indicate transmural myocardial infarction. An elevation of >1mm and longer than 80 milliseconds following the J-point. This measure has a false positive rate of 15-20% (which is slightly higher in women than men) and a false negative rate of 20-30%.[1]
  • ST depression may be associated with subendocardial myocardial infarction, hypokalemia, or digitalis toxicity.[2]

In fetal monitoring

In fetal electrocardiography, ST waveform analysis (sometimes abbreviated STAN) is used to get an indication of increasing levels of fetal base deficit.[3]

References

1. ^{{cite book |author=Sabatine MS|title=Pocket Medicine (Pocket Notebook) |publisher=Lippincott Williams & Wilkins |year=2000 |pages= |isbn=0-7817-1649-7 |oclc= |doi=}}
2. ^{{cite web|url=http://www.uab.edu/emig/yellow_book/yb_reading_ekg.htm|title=404 - Error: 404 Page not found|author=|date=|website=www.uab.edu|accessdate=11 April 2018}}
3. ^{{Cite journal | last1 = Mansano | first1 = R. Z. | last2 = Beall | first2 = M. H. | last3 = Ross | first3 = M. G. | doi = 10.1080/14767050601055279 | title = Fetal ST segment heart rate analysis in labor: Improvement of intervention criteria using interpolated base deficit | journal = Journal of Maternal-Fetal and Neonatal Medicine | volume = 20 | issue = 1 | pages = 47–52 | year = 2007 | pmid = 17437199 | pmc = }}
{{Cardiovascular physiology}}

1 : Cardiac electrophysiology

随便看

 

开放百科全书收录14589846条英语、德语、日语等多语种百科知识,基本涵盖了大多数领域的百科知识,是一部内容自由、开放的电子版国际百科全书。

 

Copyright © 2023 OENC.NET All Rights Reserved
京ICP备2021023879号 更新时间:2024/11/10 22:47:45