Quantitative analysis of segmental wall motion during maximal upright dynamic exercise: variability in normal adults

Area of Science:

• Cardiology
• Physiology
• Medical Imaging

Background:

• Regional left ventricular endocardial motion variability is present at rest.
• Understanding this variability during exercise is crucial for accurate clinical interpretation.

Purpose of the Study:

• To determine if regional left ventricular endocardial motion variability persists at peak exercise.
• To compare rest and exercise-induced changes in segmental wall motion.

Main Methods:

• Two-dimensional echocardiography in 25 healthy adults at rest and peak exercise.
• Digitization and computer-aided analysis of 32 radial left ventricular segments.
• Quantification of percent segmental area reduction for septum, apex, and lateral wall.

Main Results:

• Percent area reduction significantly increased from rest to peak exercise across all regions (p < .001).
• Considerable inter-segment variability in motion was observed within individuals at both rest and peak exercise.
• The difference between minimal and maximal percent area reduction was substantial in healthy individuals.

Conclusions:

• Significant variability in normal left ventricular endocardial motion exists, even during maximal exercise.
• Qualitative assessments of 'hypokinesis' may represent normal physiological variation.
• Segmental akinesis or dyskinesis, though rare at rest and absent at peak exercise, should be considered abnormal.