Section of Cardiovascular Imaging, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio.
Section of Invasive and Interventional Cardiology, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio.
Am J Physiol Heart Circ Physiol. 2022 Jan 1;322(1):H94-H104. doi: 10.1152/ajpheart.00183.2021. Epub 2021 Dec 3.
Dobutamine stress echocardiography (DSE) is a useful tool for assessing low-gradient significant aortic stenosis (AS) and contractile reserve (CR), but its prognostic utility has become controversial in recent studies. We evaluated the impact of DSE on aortic valve physiological, structural, and left ventricular parameters in low-gradient AS. Consecutive patients undergoing DSE for low-gradient AS evaluation from September 2010 to July 2016 were retrospectively studied, and DSE findings were divided into four groups: with and without severe AS and/or CR. Relationships between left ventricular chamber quantification, CR, aortic valve Doppler during DSE, and calcium score [by computerized tomography (CT)] were analyzed. There were 258 DSE studies performed on 243 patients, mean age 77.6 ± 10.8 yr and 183 (70.1%) were males. With increasing dobutamine dose, apart from systolic blood pressure, left ventricular ejection fraction, flow, cardiac power output, and longitudinal strain magnitude, along with aortic valve area and mean aortic gradient were all significantly increased ( < 0.05). Flow and mean gradient increased in both the presence and absence of CR, whereas stroke volume and aortic valve area increased mainly in those with CR only. The aortic valve area increased in both patients with low and high calcium scores; however, the baseline area was lower in those with a higher calcium score. During DSE, aortic valve area increases with increase in aortic valve gradient. Higher calcium score is associated with lower baseline aortic valve area, but the aortic valve area still increases with dobutamine even in presence of a high calcium score. We show that even in most severe aortic stenosis, there is some residual valve pliability. This suggests that a complete loss of pliability is not compatible with survival.
多巴酚丁胺负荷超声心动图（DSE）是评估低梯度重度主动脉瓣狭窄（AS）和收缩储备（CR）的有用工具，但在最近的研究中，其预后价值存在争议。我们评估了 DSE 对低梯度 AS 主动脉瓣生理、结构和左心室参数的影响。回顾性研究了 2010 年 9 月至 2016 年 7 月间因低梯度 AS 评估而行 DSE 的连续患者，并将 DSE 结果分为四组：有无严重 AS 和/或 CR。分析了左心室腔定量、CR、DSE 期间主动脉瓣多普勒和钙评分（通过计算机断层扫描（CT））之间的关系。对 243 例患者的 258 次 DSE 研究，平均年龄 77.6±10.8 岁，183 例（70.1%）为男性。随着多巴酚丁胺剂量的增加，除了收缩压、左心室射血分数、流量、心脏功率输出和纵向应变幅度外，主动脉瓣面积和平均主动脉梯度也显著增加（<0.05）。在有或无 CR 的情况下，流量和平均梯度均增加，而只有在有 CR 的情况下，每搏量和主动脉瓣面积才增加。低钙和高钙评分患者的主动脉瓣面积均增加；然而，在钙评分较高的患者中，基线面积较低。在 DSE 期间，主动脉瓣面积随主动脉瓣梯度的增加而增加。较高的钙评分与较低的基线主动脉瓣面积相关，但即使在高钙评分的情况下，主动脉瓣面积仍随多巴酚丁胺而增加。我们表明，即使在最严重的主动脉瓣狭窄中，仍存在一些残余瓣弹性。这表明完全丧失弹性与生存不相容。
