Johnson Jake, Soppet Jenelle, Sutherland-Smith James, Sato Amy, Cunningham Suzanne M, Cortez Keaton, Anson Agustina
Cummings School of Veterinary Medicine At Tufts University, North Grafton, Massachusetts, USA.
Vet Radiol Ultrasound. 2025 Sep;66(5):e70066. doi: 10.1111/vru.70066.
Echocardiography and radiography are frequently used to evaluate left atrial size, which serves as an important prognostic marker for canine cardiac conditions. However, there are no published criteria in veterinary medicine that allow for non-ECG gated CT to detect the presence or absence of left atrial enlargement (LAE). The availability of a validated measurement of left atrial size would have the potential to improve the detection of cardiac disease in dogs having thoracic exams for non-cardiovascular reasons. The objective of this study was to evaluate a non-ECG gated CT left atrium-to-aortic diameter ratio (LA:Ao) for detecting LAE, while using a two-dimensional (2D) echocardiogram as the gold standard. One hundred twenty-three dogs that underwent thoracic non-ECG gated CT and echocardiogram within 1 month of one another were evaluated retrospectively. Thirty-three dogs were diagnosed with LAE on 2D echocardiogram (short axis LA:Ao ≥ 1.6) while 90 dogs had a normal left atrial size. The CT LA:Ao was not a sensitive discriminator for LAE in dogs; however, larger ratios were highly specific. Dogs with a CT LA:Ao ≥ 3.4 (97% specificity, 15% sensitivity, 71% PPV, and 76% NPV) may benefit from further evaluation with an echocardiogram at the discretion of the clinical care team. Overall, the method evaluated in this study was not able to reliably detect dogs that have echocardiographically confirmed LAE and, as such, appears to have low clinical utility. The use of multiplanar reconstructed images to emulate the right parasternal short-axis plane is recommended for future studies.
超声心动图和放射成像常用于评估左心房大小，左心房大小是犬类心脏疾病的重要预后指标。然而，兽医学领域尚无已发表的标准可用于非心电图门控CT检测左心房扩大（LAE）的有无。获得经过验证的左心房大小测量方法有可能改善对因非心血管原因进行胸部检查的犬类心脏病的检测。本研究的目的是评估非心电图门控CT的左心房与主动脉直径比（LA:Ao）以检测LAE，同时将二维（2D）超声心动图作为金标准。对123只在1个月内先后接受胸部非心电图门控CT和超声心动图检查的犬进行回顾性评估。33只犬在二维超声心动图上被诊断为LAE（短轴LA:Ao≥1.6），而90只犬左心房大小正常。CT的LA:Ao对犬类LAE并非敏感的鉴别指标；然而，比值越大特异性越高。CT的LA:Ao≥3.4的犬（特异性97%，敏感性15%，阳性预测值71%，阴性预测值76%），临床护理团队可酌情考虑通过超声心动图进行进一步评估。总体而言，本研究评估的方法无法可靠地检测出经超声心动图证实有LAE的犬，因此其临床实用性似乎较低。建议未来研究使用多平面重建图像来模拟右胸骨旁短轴平面。
