Echocardiography of left ventricle in horses given atropine-dobutamine.

摘要

Echographic parameters of the left ventricle during an atropine-low dose dobutamine stress test in adult horses is described. Six healthy 7-15y untrained Kord horses were used. Heart rate and left ventricular B- and M-mode dimensions were recorded atbaseline during administration of 35 mg/kg atropine IV followed by incremental infusions of 2 to 6 mg/kg/min butamine. Heart rates increased 148.2 ± 11.5 bpm at greatest infusion rate. Systolic interventricular septum thickness (IST) increased from 4.31 ± 0.17 to 5.35 ± 0.21cm, diastolic IST from 2.75 ± 0.15 to 3.69 ± 0.11 cm, systolic left ventricular free wall thickness (SLVFWT) from 2.75 ± 0.15 to 3.69 ± 0.11cm and diastolic SLVFWT from 3.42 ± 0.30 to 4.50 ± 0.18cm. Fractional shortening increased 2.24 ± 0.28 to 2.85 ± 0.24 cm reaching maximum at from 34.55 ± 3.52 to 49.66 ± 2.92% infusion. Systolic and diastolic left ventricular internal diameter and left ventricular external and internal area declined 2 mg/kg/min infusionbut not higher. Systolic and diastolic myocardial area declined at administration but not infusion of dobutamine. All changes or values described above were significant (P < 0.05). Results suggest that the test induced significant changes in left ventricular echocardiographic parameters in adult Kord horses and thus, may have diagnostic value in cardiac disease.