[Pre-ejection flow in the left ventricular outflow tract: a pulsed Doppler echocardiographic study]

Area of Science:

• Cardiology
• Cardiovascular Physiology
• Echocardiography

Context:

• Pre-ejection flow (PEF) is a brief flow towards the cardiac base in the left ventricular outflow tract.
• Understanding PEF's genesis is crucial for assessing cardiac function.

Purpose:

• To investigate the contribution of left ventricular contraction to PEF genesis.
• To analyze PEF characteristics in patients with lone atrial fibrillation (Af) and premature ventricular contractions (PVC) using pulsed Doppler echocardiography.

Summary:

• PEF was analyzed in 20 patients with Af and 30 with PVC, simultaneously recording phonocardiograms and electrocardiograms.
• PEF appeared after the Q wave in Af and PVC, unlike sinus rhythm, and its peak coincided with the first heart sound.
• PEF duration was shorter in Af (60.6 ± 14.2 msec) than in sinus rhythm (93.6 ± 15.4 msec) or PVC (87.5 ± 19.4 msec).
• Peak PEF velocities were significantly lower in Af and PVC compared to sinus rhythm.
• Lower peak PEF velocities were noted in PVC with left bundle branch block compared to right bundle branch block.

Impact:

• This study clarifies the impact of arrhythmias like Af and PVC on left ventricular hemodynamics.
• Findings contribute to a better understanding of how cardiac electrical and mechanical events influence early systolic flow.
• Provides insights into potential echocardiographic markers for evaluating ventricular dysfunction in arrhythmias.