Effects of incremental beta blocker dosing on myocardial mechanics of the left ventricle:MRI 3D Tagging insight
Abstract：Objective MRI Tagging was applied to detect different effects on myocytes by different doses of β-blocker.Methods 13 healthy volunteers attended this research by MRI tagging during escalated administration of Esmolol.The circumferential,longitudinal and radial myocardial shortening was determined for each dose.The curves were analyzed for peak value,time-to-peak,upslope,and area-under-the-curve.Results At low doses,from 5-25 μg·kg-1·min-1,the peak value increased,while time-to-peak decreased,yielding a steeper upslope.Combining the values revealed a left shift of the curves at low doses when compared to the curve without Esmolol.At doses of 50-150 μg·kg-1·min-1,a right shift with flattening occurred indicating less pronounced shortening as sign of negative inotropy.Conclusion Differences were found in healthy volunteers in the myocardial effects of beta-blockade at low compared to high dosage.It is tempting to speculate that the response to β-blockade could be even more pronounced in patients suffering from ventricular hypertrophy due to the higher prevalence of the transversely intruding cardiomyocytes.MRI tagging is helpful to monitor dosing.
Keywords：CardiomyocyteBeta-blockersMRI Tagging
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 837-840,后插3-后插4 )