Shin Edward D, Fan Eugene
Department of Medicine, Kaiser Permanente Oakland Medical Center, 3701 Broadway, 4th Floor, Oakland, CA 94611, USA.
Eur Heart J Case Rep. 2024 Sep 14;8(10):ytae501. doi: 10.1093/ehjcr/ytae501. eCollection 2024 Oct.
Aortic stenosis (AS) is the most commonly acquired valvular pathology in the western world. Aortic stenosis severity is typically evaluated with Doppler echocardiography. Evaluation of aortic gradients using standard Doppler echocardiography from the apical window may underestimate the true gradient due to misalignment of blood flow to the ultrasound beam and is often better evaluated from other imaging windows using a non-imaging continuous wave Doppler (NI-CWD) probe. Herein, we describe a unique case of AS being underestimated by dynamic acoustic shadowing from the apical window rather than beam misalignment.
The patient is a Hispanic 31-year-old male with a congenital bicuspid aortic valve who underwent a balloon aortic valvuloplasty at age 13. At age 31, the patient underwent a repeat transthoracic echocardiogram (TTE) that was largely unchanged from his prior TTE from 15 years prior. Notably on this TTE, there was acoustic shadowing of colour Doppler in the distal left ventricular outflow tract and aortic valve during systole. While gradients only suggested moderate AS, the degree of left ventricular hypertrophy was suspicious for more severe AS. Only by using the NI-CWD probe at the right sternal border were we able to identify very severe AS with a peak velocity of 6.5 m/s and a mean gradient of 100 mmHg.
In our specific case, dynamic acoustic shadowing of the aortic valve from the apical window obscured both imaging and Doppler signals. This acoustic shadowing was not present from the right sternal border with the NI-CWD probe, leading to an over 100% increase in aortic valve peak velocity and proper correction of AS severity. This allowed for expedited care and underscores the importance of such techniques.
在西方世界，主动脉瓣狭窄（AS）是最常见的后天性瓣膜病变。主动脉瓣狭窄的严重程度通常通过多普勒超声心动图进行评估。使用标准多普勒超声心动图从心尖窗评估主动脉瓣压差可能会因血流与超声束未对准而低估真实压差，通常使用非成像连续波多普勒（NI-CWD）探头从其他成像窗进行评估会更好。在此，我们描述了一个独特的病例，即心尖窗的动态声学阴影而非束未对准导致主动脉瓣狭窄被低估。
患者是一名31岁的西班牙裔男性，患有先天性二叶主动脉瓣，13岁时接受了球囊主动脉瓣成形术。31岁时，患者接受了重复经胸超声心动图（TTE）检查，结果与15年前的前一次TTE基本相同。值得注意的是，在这次TTE检查中，收缩期左心室流出道远端和主动脉瓣处彩色多普勒存在声学阴影。虽然压差仅提示中度主动脉瓣狭窄，但左心室肥厚程度怀疑有更严重的主动脉瓣狭窄。仅通过在右胸骨旁使用NI-CWD探头，我们才能够识别出非常严重的主动脉瓣狭窄，峰值速度为6.5 m/s，平均压差为100 mmHg。
在我们的具体病例中，心尖窗对主动脉瓣的动态声学阴影掩盖了成像和多普勒信号。使用NI-CWD探头在右胸骨旁时不存在这种声学阴影，导致主动脉瓣峰值速度增加超过100%，并正确校正了主动脉瓣狭窄的严重程度。这使得能够加快治疗，并强调了此类技术的重要性。
