Left ventricular torsion parameters are affected by acute changes in load.

Area of Science:

• Cardiology
• Cardiac Physiology
• Echocardiography

Background:

• Left ventricular (LV) torsion quantification offers novel insights into systolic and diastolic function.
• Understanding the impact of acute load manipulation on LV torsion is crucial for accurate functional assessment.

Purpose of the Study:

• To investigate the effects of acute preload and afterload alterations on left ventricular torsion in human subjects.
• To characterize changes in LV torsion parameters and their timing relative to cardiac events under varying loading conditions.

Main Methods:

• Simultaneous LV pressure and echocardiographic measurements were performed in 18 patients with normal systolic function.
• Cardiac loading was modulated sequentially using glyceryl trinitrate (GTN) and saline fluid loading.
• Echocardiographic speckle tracking imaging quantified LV torsion and its timing relative to mitral valve opening (MVO).

Main Results:

• GTN administration reduced preload and afterload, augmenting peak torsion and systolic torsion velocity, and advancing untwisting onset.
• Fluid loading increased preload and afterload, decreasing the proportion of early untwisting and delaying peak untwisting, without affecting systolic torsion.
• LV torsion parameters demonstrated significant sensitivity to acute changes in preload and afterload.

Conclusions:

• Left ventricular torsion is highly responsive to acute alterations in cardiac loading conditions.
• Clinical interpretation of LV torsion indices must account for the patient's current hemodynamic and loading status.