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Systolic time intervals in children with heart disease
Insights
Systolic time intervals, including the preejection period/left ventricular ejection time (PEP/LVET) quotient, effectively assess pediatric heart conditions. This non-invasive method aids in diagnosing left ventricular failure and monitoring various pediatric heart diseases.
Area of Science:
- Pediatric Cardiology
- Non-invasive Cardiac Diagnostics
- Cardiovascular Physiology
Background:
- The preejection period (PEP) correlates with isometric contraction time.
- Increased PEP/LVET ratio is a key indicator of left ventricular failure.
- Systolic time intervals (STIs) offer valuable insights into cardiac function.
Purpose of the Study:
- To evaluate the utility of STIs, specifically PEP/LVET, in assessing cardiac function in children.
- To investigate the correlation of PEP/LVET with various pediatric heart diseases.
- To establish normal PEP/LVET values in healthy children.
Main Methods:
- Recording of systolic time intervals from carotid pulse curves.
- Analysis of PEP/LVET in 40 normal children (aged 5 and 10 years).
- Investigation of 78 children with diverse heart conditions.
Main Results:
- Normal PEP/LVET in healthy children was 0.31 +/- 0.04.
- PEP/LVET showed inverse correlation with R-R interval in heart block/extrasystole patients.
- PEP/LVET differentiated shunt sizes in VSDs, normalizing post-surgery.
- Elevated PEP/LVET in TGA indicated right ventricular inadequacy.
- "Normalization" of decreased PEP/LVET in aortic stenosis suggested early LV failure.
Conclusions:
- Non-invasive STI measurements, particularly PEP/LVET, are valuable for diagnosing and monitoring pediatric heart diseases.
- PEP/LVET serves as a sensitive indicator for left ventricular function and failure in children.
- STI analysis provides a more accessible method for tracking cardiac function compared to invasive techniques.
Abstract:
Of the systolic time intervals, the preejection period is known to correlate well with invasively measured isometric contraction time, and increase of the quotient preejection period/left ventricular ejection time (PEP/LVET) is considered to be of a good indicator of left ventricular failure. The different systolic time intervals have been recorded from the carotid pulse curve from 40 normal children, 20 aged five and 20 aged ten years. Their PEP/LVET was 0.31 +/- 0.04. Seventy-eight children with different heart diseases were then investigated. In patients with congenital total heart block or extrasystoles, there was a negative correlation between PEP/LVET and the R-R interval, in accordance with the Frank-Starling law. In patients with ventricular septal defects PEP/LVET differentiates between small and large shunts; the increased PEP/LVET of the latter normalizes after operation. The increased PEP/RVET of children with transposition of the great arteries is an expression of the inadequacy of the right ventricle as a systemic chamber. In aortic stenosis "normalization" of a previously decreased PEP/LVET may indicate early left ventricular failure. In primary myocardial disease registration of the systolic time intervals enables us to follow the left ventricular function more closely than is possible with invasive techniques.