Left ventricular geometry immediately following defibrillation-strength shocks

V. Ramanathan, B. K. Hoffmeister, Amy Curry

Research output: Contribution to journalConference article

Abstract

A previous 2D ultrasound study suggested that there is relaxation of the myocardium after defibrillation. However, that 2D study could not measure activity occurring within the first 33 ms following the shock. Thus, the objective of our study is to determine the left ventricular (LV) geometry during this period. Biphasic defibrillation shocks were delivered in seven dogs. One-dimensional, short-axis ultrasound images of the LV cavity were acquired, the boundary of the anterior and posterior endocardial walls was extracted, and the distance between them computed from 32 ms before to 32 ms after the shock. The normalized mean pre- and post-shock slopes are 0.2 ± 2.2 and 3.3 ± 7.9% /10 ms, respectively. The post-shock LV diameter slope is positive in the first 32 ms following both successful and unsuccessful defibrillation shocks (p<0.05). Therefore, our results confirm that the bulk of the myocardium is relaxing immediately after defibrillation shocks.

Original languageEnglish (US)
Pages (from-to)241-242
Number of pages2
JournalComputers in Cardiology
StatePublished - Dec 1 2001
Externally publishedYes
EventComputer in Cardiology 2001 - Rotterdam, Netherlands
Duration: Sep 23 2001Sep 26 2001

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Shock
Ultrasonics
Geometry
Myocardium
Dogs

All Science Journal Classification (ASJC) codes

  • Computer Science Applications
  • Cardiology and Cardiovascular Medicine

Cite this

Left ventricular geometry immediately following defibrillation-strength shocks. / Ramanathan, V.; Hoffmeister, B. K.; Curry, Amy.

In: Computers in Cardiology, 01.12.2001, p. 241-242.

Research output: Contribution to journalConference article

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