Lin S S, Roger V L, Pascoe R, Seward J B, Pellikka P A
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA.
Am Heart J. 1998 Dec;136(6):1010-6. doi: 10.1016/s0002-8703(98)70157-7.
This study was designed to describe the experience of our center with the safety and feasibility of dobutamine stress echocardiography (DSE) in aortic stenosis (AS), to characterize the hemodynamic response to dobutamine infusion, and to examine the hemodynamic response in relation to the anatomic evaluation of the valve among patients who underwent valve replacement.
The diagnosis of the hemodynamic severity of AS can be difficult when the cardiac output is reduced and the gradient is low, but the effective valve area calculates to be small. DSE has been proposed as a means of assessing the severity of AS in this setting.
We reviewed 27 patients (18 men, 9 women; mean age 71 +/- 12 years) with AS who underwent DSE between 1991 and 1996.
Fifteen (55%) patients were New York Heart Association class III or IV, 8 (30%) had angina Canadian class III or IV, and 3 (11%) syncope. Dobutamine peak dose was 27 +/- 11 micrograms/kg/min. Sixteen (59%) patients had mild side effects. DSE resulted in a significant increase in the cardiac output from 4.1 +/- 1.2 L/min at rest to 7.3 +/- 1.9 L/min at peak dose, and in heart rate (76 +/- 16 beats/min to 124 +/- 20 beats/min), systolic blood pressure (128 +/- 26 mm Hg to 137 +/- 26 mm Hg), ejection fraction (38% +/- 20% to 42% +/- 20%), and transvalvular mean gradient (28 +/- 10 mm Hg to 39 +/- 9 mm Hg) (P <.05). There was also a significant increase in the valve area from 0.77 +/- 0.14 cm2 at rest to 0.97 +/- 0.21 cm2 (P <.001). Seven patients underwent surgery; all valves were severely calcified, confirming anatomic disease. In this group, an increase in the mean gradient but also a trend toward an increase in the valve area were noted in response to dobutamine: 33 +/- 10 mm Hg to 47 +/- 6 mm Hg and 0.79 +/- 0.11 cm2 to 0.95 +/- 0.19 cm2, respectively.
Although more data are needed to fully establish the safety of the test in this indication, this study suggests that patients with AS can safely undergo DSE. Dobutamine results in an increase not only in the mean gradient, but also in the valve area. An increase in valve area with dobutamine was observed in some patients with anatomically confirmed severe AS and thus does not exclude fixed valve disease.
本研究旨在描述我们中心在主动脉瓣狭窄（AS）患者中进行多巴酚丁胺负荷超声心动图（DSE）的安全性和可行性经验，描述对多巴酚丁胺输注的血流动力学反应，并在接受瓣膜置换的患者中研究与瓣膜解剖评估相关的血流动力学反应。
当心输出量降低且压力阶差较低，但有效瓣口面积计算显示较小时，AS血流动力学严重程度的诊断可能会很困难。DSE已被提议作为评估这种情况下AS严重程度的一种方法。
我们回顾了1991年至1996年间接受DSE检查的27例AS患者（18例男性，9例女性；平均年龄71±12岁）。
15例（55%）患者为纽约心脏协会III或IV级，8例（30%）有加拿大心血管学会III或IV级心绞痛，3例（11%）有晕厥。多巴酚丁胺峰值剂量为27±11微克/千克/分钟。16例（59%）患者有轻度副作用。DSE导致心输出量从静息时的4.1±1.2升/分钟显著增加至峰值剂量时的7.3±1.9升/分钟，心率（从76±16次/分钟增至124±20次/分钟）、收缩压（从128±26毫米汞柱增至137±26毫米汞柱）、射血分数（从38%±20%增至42%±20%）和跨瓣平均压力阶差（从28±10毫米汞柱增至39±9毫米汞柱）均显著增加（P<.05）。瓣口面积也从静息时的0.77±0.14平方厘米显著增加至0.97±0.21平方厘米（P<.001）。7例患者接受了手术；所有瓣膜均严重钙化，证实存在解剖学病变。在这组患者中，多巴酚丁胺导致平均压力阶差增加，瓣口面积也有增加趋势：分别从33±10毫米汞柱增至47±6毫米汞柱和从0.79±0.ll平方厘米增至0.95±0.19平方厘米。
尽管需要更多数据来充分确立该检查在此适应证中的安全性，但本研究表明AS患者可安全地接受DSE检查。多巴酚丁胺不仅导致平均压力阶差增加，还使瓣口面积增加。在一些解剖学证实为严重AS患者中观察到多巴酚丁胺使瓣口面积增加，因此并不排除存在固定性瓣膜病变。
