McEntee K, Clercx C, Amory H, Michaux C, Dardenne J J, Soyeur D, Henroteaux M
Small Animal Clinic, Faculty of Veterinary Medicine, University of Liège, Belgium.
Am J Vet Res. 1999 Jul;60(7):865-71.
To evaluate left and right ventricular filling and ejection performances by use of Doppler echocardiography in healthy, conscious dogs submitted to dobutamine stress testing.
10 unsedated, healthy adult Beagles.
Doppler echocardiography was performed during cardiac stress testing on each dog twice at 24-hour intervals. Dobutamine was infused in 10 micrograms/kg of body weight/min incremental dosages, from 12.5 to 42.5 micrograms/kg/min. Duration of each step was 15 minutes. Doppler measurements were recorded at baseline and at each stage of dobutamine infusion, whereas aortic diameter was measured at baseline and at peak dosage by use of two-dimensional echocardiography.
Dobutamine infusion induced a significant increase in velocity time integrals and in peak flow velocities at the aortic, pulmonic, mitral, and tricuspid valves. Acceleration time-to-deceleration time ratio at the aortic wave also was increased significantly. On the other hand, ejection time, acceleration time, and deceleration time at the aortic and pulmonic valves and peak flow velocity of the E wave-to-peak flow velocity of the A wave ratio at the mitral and tricuspid valves decreased significantly during the test. The acceleration time-to-deceleration time ratio at the pulmonic wave was unchanged. A significant, progressive increase in cardiac index also was observed during dobutamine infusion, with a maximal increase of 104% from baseline. This was mediated initially by an increase in stroke index and, at higher dosages, by an increase in heart rate.
Doppler echocardiography performed during dobutamine stress testing may be a reliable method of assessing myocardial function in dogs with cardiovascular disease.
通过多普勒超声心动图评估接受多巴酚丁胺负荷试验的清醒健康犬的左右心室充盈及射血功能。
10只未使用镇静剂的健康成年比格犬。
在心脏负荷试验期间，每隔24小时对每只犬进行两次多普勒超声心动图检查。多巴酚丁胺以10微克/千克体重/分钟的递增剂量静脉输注，从12.5微克/千克/分钟增至42.5微克/千克/分钟。每个阶段持续15分钟。在基线以及多巴酚丁胺输注的每个阶段记录多普勒测量值，而使用二维超声心动图在基线和峰值剂量时测量主动脉直径。
多巴酚丁胺输注导致主动脉、肺动脉、二尖瓣和三尖瓣处的速度时间积分和峰值流速显著增加。主动脉波的加速时间与减速时间之比也显著增加。另一方面，在试验期间，主动脉和肺动脉瓣处的射血时间、加速时间和减速时间以及二尖瓣和三尖瓣处E波峰值流速与A波峰值流速之比显著降低。肺动脉波的加速时间与减速时间之比未改变。在多巴酚丁胺输注期间还观察到心脏指数显著、逐渐增加，相对于基线最大增加104%。这最初由每搏量指数增加介导，在更高剂量时由心率增加介导。
在多巴酚丁胺负荷试验期间进行的多普勒超声心动图检查可能是评估患有心血管疾病犬心肌功能的可靠方法。
