Exaggerated respiratory variation in left ventricular ejection time during lax pericardial effusion.

Area of Science:

• Cardiology
• Physiology

Background:

• Pericardial effusions can affect cardiac function.
• Subtle changes in cardiac function may precede overt signs of cardiac compression.

Purpose of the Study:

• To investigate the impact of echocardiographic pericardial effusions on left ventricular ejection time (LVET) during respiration.
• To determine if respiratory variations in LVET can serve as an early indicator of pericardial effusion effects.

Main Methods:

• Studied 20 consecutive patients with echocardiographic pericardial effusions but no signs of cardiac embarrassment.
• Measured left ventricular ejection time (LVET) changes during inspiration (delta LVET).
• Compared delta LVET in patients with effusions to normal subjects.

Main Results:

• Patients with pericardial effusions showed a significantly greater fall in LVET during inspiration (18.3 ms) compared to normal subjects (7.0 ms).
• Abnormal delta LVET was most pronounced in patients with smaller effusions.
• Ejection time indices indicated diminished stroke volume specifically during inspiration.

Conclusions:

• Pericardial fluid, even without overt cardiac compression, exaggerates respiratory effects on left ventricular function.
• The consistent exaggeration of delta LVET in small effusions is physiologically significant.
• Abnormal delta LVET may have diagnostic value for detecting early effects of pericardial effusions.