[Day-to day variability of cardiac pressure values in horses measured with right heart catheterization on 3 consecutive days].

This research study examined the day-to-day variation in cardiac pressure values in 17 healthy horses measured over three consecutive days. The results indicate that almost all pressure measurements had a low daily effect on variation, suggesting that a single day’s cardiac pressure measurement may be sufficient.

Research Methodology

• The research team conducted right heart catheterization on 17 healthy horses across three consecutive days.
• During this procedure, cardiac pressure values were measured at various points: the right atrium, the right ventricle, the pulmonary artery, and the pulmonary capillaries (pulmonary artery wedge pressure).
• The study also explored whether heart rate influenced cardiac pressure variability and if there were differences in these values between trained and untrained horses.
• Using the coefficient of variances and variance components assessment, the team analyzed the variation among repeated measurements within a day and a horse, and those over three days and also within different horses (day-to-day intraindividual variation and interindividual variation).

Results and Findings

• The calculated absolute interindividual variance ranged between 0.4 and 19.6 for pressure values and heart rate across all horses and days.
• The variation in heart rate and pressure values was lower for untrained horses compared to trained horses.
• Significant differences were observed between trained and untrained horses particularly with right atrial mean pressure and right atrial diastolic pressure.
• The mean heart rate’s coefficient of variances was 11.8%, while different pressure values had coefficients ranging between 13.1% (mean pulmonary artery pressure) and 46.4% (right ventricular pressure).
• When dividing the variances, researchers found that 54.4-78.9% of variation was due to the effect of days, 6.2-30.7% due to the effect of different horses, and 12.5-23% due to repeated measurements on different days.

Conclusion

• The findings show that nearly all the pressure values had a small effect of days on variation.
• This suggests that cardiac pressure measurements taken on one day could be sufficient, reducing the need for day-to-day repetitive measurements in horses.