Abstract
BACKGROUND: Sedation is an essential part of clinical practice. Despite this fact, we still lack data describing the exact impact of sedation on heart function.
PURPOSE: To compare the changes in heart function, induced after sedation with either midazolam or dexmedetomidine, using cardiac magnetic resonance imaging (MRI). METHODS: A total number of 30 volunteers were randomized into two groups: 15 participants in the midazolam group (MID) and 15 participants in the dexmedetomidine group (DEX).
Every participant underwent a one-session cardiac MRI before and after sedation onset. The following parameters were recorded: left and right ventricle stroke volume (Ao-vol and Pul-vol resp.) and maximum flow velocity through the mitral valve during early (E-diast) and late diastole (L-diast).
A monitor recorded values of mean blood pressure (MAP), pulse (P) and blood oxygen saturation (SpO(2)) in 5-minute intervals. RESULTS: Dexmedetomidine led to a statistically signifi cant decrease in Ao-vol (p = 0.006) and Pul-vol (p = 0.003), while midazolam decreased E-diast (p = 0.019) Ao-vol (p = 0.001) and Pul-vol (p = 0.01).
The late diastolic filling was not influenced by the sedation technique. CONCLUSION: Both sedation regimens worsened the systolic function of both ventricles.
Midazolam moreover attenuated early diastolic filling of the left ventricle (Tab. 3, Fig. 4, Ref. 19).