Accelerometer-Measured Physical Activity After Mitral Valve Surgery: An Analysis of the UK Mini Mitral Randomized...

Area of Science:

• Cardiovascular Surgery
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Wearable accelerometers offer objective measurement of physical activity and sleep, bypassing self-report limitations.
• Previous studies have not utilized randomized controlled trials to assess accelerometer utility in post-cardiac surgery recovery.
• The UK Mini Mitral trial provides a unique dataset for this secondary analysis.

Purpose of the Study:

• To evaluate the effectiveness of wearable accelerometers in measuring and comparing physical function recovery after cardiac surgery.
• To compare recovery trajectories between sternotomy and minimally invasive thoracoscopic mitral valve repair using accelerometry data.

Main Methods:

• Secondary analysis of the UK Mini Mitral trial data.
• Patients (n=230) wore wrist-worn accelerometers pre-surgery and at multiple time points up to 52 weeks post-surgery.
• Analysis focused on changes in activity counts, moderate-to-vigorous activity, light activity, sedentary time, sleep duration, and sleep efficiency.

Main Results:

• Minimally invasive thoracotomy (Mini) group showed significantly higher total activity counts and moderate-to-vigorous physical activity at 6 and 18 weeks compared to sternotomy.
• The Mini group also exhibited lower sedentary time and higher light physical activity at specific time points.
• No significant differences in sleep duration were observed, but sleep efficiency was higher in the Mini group at 12 weeks.

Conclusions:

• Wearable accelerometers are a viable tool for objectively comparing recovery of physical function after different surgical approaches.
• Patients undergoing minimally invasive mitral valve repair demonstrated an earlier and more robust recovery of physical activity.
• Sternotomy patients showed a sustained decline in activity levels up to 52 weeks post-surgery.