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[The atrioventricular valve opening time on the normal echocardiogram]
Zeitschrift Fur Kardiologie
|June 1, 1983
Summary
The study measured the time from the QRS complex to atrioventricular valve opening (Q-Dt) in healthy volunteers and patients. Prolonged Q-Dt in patients suggests impaired isovolumic relaxation, impacting diastolic filling.
Area of Science:
- Cardiology
- Echocardiography
- Physiology
Context:
- Assessing the electromechanical timing of the heart is crucial for understanding cardiac function.
- The atrioventricular (AV) valve opening time, specifically the Q-Dt interval, reflects key phases of the cardiac cycle.
- Previous studies have not fully elucidated the relationship between Q-Dt and diastolic dysfunction.
Purpose:
- To measure the Q-Dt interval for the tricuspid valve (TV) and mitral valve (MV) in healthy individuals.
- To investigate the correlation between Q-Dt prolongation and cardiac conditions like heart failure.
- To explore the role of isovolumic relaxation time (IRT) in determining Q-Dt.
Summary:
- Q-Dt, the time from QRS onset to AV valve opening, was measured using echocardiography and atrial stimulation in 54 healthy volunteers.
- Normal Q-Dt values were established for TV (408 ms) and MV (428 ms) at a heart rate of approximately 72 beats/min.
- Prolongation of Q-Dt in patients, particularly those with heart failure, was linked to impaired isovolumic relaxation and altered diastolic filling patterns.
Impact:
- This research provides normative Q-Dt values for assessing cardiac timing.
- Findings suggest that prolonged Q-Dt may serve as an indicator of isovolumic relaxation dysfunction.
- Understanding Q-Dt variations can aid in the diagnosis and management of diastolic heart dysfunction.