Systolic time intervals by echocardiography

Circulation
|January 1, 1975
PubMed

Insights

A novel echocardiogram method accurately measures systolic time intervals when traditional phonocardiograms fail. This noninvasive technique offers a reliable alternative for crucial cardiac assessments.

Area of Science:

  • Cardiology
  • Medical Imaging
  • Biomedical Engineering

Background:

  • Phonocardiograms and carotid pulses can present technical recording challenges.
  • Accurate determination of systolic time intervals is clinically significant.
  • Existing methods for measuring systolic time intervals are sometimes unreliable.

Purpose of the Study:

  • To evaluate the efficacy of aortic valve echocardiography for determining systolic time intervals.
  • To establish an alternative noninvasive method for systolic time interval measurement.
  • To compare echocardiography-derived intervals with conventional methods.

Main Methods:

  • Utilized high-speed strip chart recording of the aortic valve echocardiogram in 52 patients.
  • Calculated ejection time (aortic valve opening to closing).
  • Determined pre-ejection period (Q wave to aortic valve closing) and pre-ejection period/ejection time ratio.

Main Results:

  • Satisfactory echocardiogram recordings were obtained in 36 patients.
  • High correlation (r > 0.97) was observed between echocardiography and conventional methods.
  • Differences in measured intervals were statistically insignificant, with ejection time differing by a maximum of 16 msec.

Conclusions:

  • Aortic valve echocardiography is a viable noninvasive alternative for systolic time interval determination.
  • This method is particularly useful when conventional techniques are hindered by technical difficulties.
  • Echocardiography provides accurate and reliable systolic time interval data.

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