To Ada, Hostnik Eric T, Rhinehart Jaylyn D, Scansen Brian A
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio.
Department of Clinical Sciences, College of Veterinary Medicine, Colorado State University, Fort Collins, Colorado.
Vet Radiol Ultrasound. 2019 Mar;60(2):145-158. doi: 10.1111/vru.12701. Epub 2018 Nov 26.
Pulmonary valve stenosis (PS) is one of the most commonly diagnosed congenital heart defects in dogs. Currently, transthoracic echocardiography (TTE) is the standard modality used to evaluate PS. Image acquisition by TTE can be challenging in some brachycephalic breeds of dogs. The use of echocardiographic-gated CT angiography (ECG-gated CTA) in veterinary medicine is limited. This retrospective method comparison study investigated right and left ventricular outflow diameters by sedated ECG-gated CTA and unsedated TTE in 14 brachycephalic dogs with PS and 12 brachycephalic dogs without PS. Measurements of ventricular outflow structures were made in early systole and end diastole for both modalities and then compared for significance between systolic and diastolic phases, as well as between the two modalities. Ratios of the pulmonary trunk diameter to the aorta at different locations (aortic valve, aortic annulus, and ascending aorta) and in different planes (transverse, sagittal) were compared between dogs with PS and without PS, as well as within dogs, by both TTE and ECG-gated CTA. Transthoracic echocardiography and ECG-gated CTA both detected significantly greater pulmonary trunk to aorta ratios in dogs with PS at all aortic locations (P < 0.05). Pulmonary valve to aortic valve ratios were significantly smaller in dogs with PS (P < 0.05). Pulmonary trunk to aorta and pulmonary valve to aorta ratios were achieved with good anatomic detail using ECG-gated CTA. Ratios of the pulmonary trunk and pulmonary valve relative to the aorta may be useful to evaluate for PS using a modality that is underutilized for cardiac assessment.
肺动脉瓣狭窄（PS）是犬类中最常见的先天性心脏缺陷之一。目前，经胸超声心动图（TTE）是用于评估PS的标准方法。在一些短头犬品种中，通过TTE进行图像采集可能具有挑战性。超声心动图门控CT血管造影（ECG门控CTA）在兽医学中的应用有限。这项回顾性方法比较研究，对14只患有PS的短头犬和12只未患PS的短头犬，采用镇静状态下的ECG门控CTA和非镇静状态下的TTE，分别测量其左右心室流出道直径。两种方法均在收缩早期和舒张末期测量心室流出结构，然后比较收缩期和舒张期之间以及两种方法之间的差异是否具有统计学意义。通过TTE和ECG门控CTA，比较了患有PS和未患PS的犬在不同位置（主动脉瓣、主动脉环和升主动脉）和不同平面（横向、矢状面）的肺动脉干直径与主动脉直径的比值。经胸超声心动图和ECG门控CTA均检测到，在所有主动脉位置，患有PS的犬的肺动脉干与主动脉的比值显著更高（P < 0.05）。患有PS的犬的肺动脉瓣与主动脉瓣的比值显著更小（P < 0.05）。使用ECG门控CTA能够清晰显示肺动脉干与主动脉以及肺动脉瓣与主动脉的比值的解剖细节。肺动脉干和肺动脉瓣相对于主动脉的比值，可能有助于使用一种在心脏评估中未得到充分利用的方法来评估PS。
