The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, UK.
Companion Care Vets Gloucester, Gloucester, Gloucestershire, UK.
Equine Vet J. 2022 Jan;54(1):176-190. doi: 10.1111/evj.13408. Epub 2021 Feb 15.
Left atrial size predicts cardiac morbidity and mortality in humans and dogs. Real-time three-dimensional echocardiography (3DE) may be reliable for assessing left atrial volume (LAV) in horses.
To determine intra- and interobserver variability estimates of 3DE-LAV and compare it to that of 2DE-LAV estimates.
Method comparison.
3DE datasets were obtained from 40 horses, then graded for quality, creating a final study population of 22 horses. The 3DE and 2DE maximum LAV (LAV ) and minimum LAV (LAV ) were measured, and left atrial emptying volume (LA EV) and left atrial ejection fraction (LA EF) were calculated, from the same 3D dataset on four occasions using (a) a semi-automatic surface recognition algorithm and (b) a modified Simpson's method of discs. 3DE LAV measurements were repeated by a second observer.
For 3DE, median LAV was 596cm for observer one, and 852 cm for observer two, LAV was 373 cm for observer one and 533 cm for observer two. Low intraobserver measurement variation was observed for LAV and LAV , with horse-level intraclass correlation coefficients (ICC ) for both observers between 76% and 85% (horse added as random effect). The interobserver ICC was 58% for LAV and 50% for LAV on averaged measurements (with observer added as random effect), indicating consistent differences between observers. While intraobserver variation was similar for 2DE LAV measurements, it was greater for LAV (ICC = 67%). The intermethod ICC for 3DE vs 2DE was low at 14% for LAV and ~0% for LAV , indicating less-consistent differences with method.
Small study population, low observer number, use of different imaging modalities (fundamental frequency and octave harmonics).
3DE assessment of LAV was reliable, suggesting suitability for longitudinal evaluation of clinical cases. Clinicians should be aware of differences in LAV measurements between observers. More defined measurement guidelines may improve repeatability.
左心房大小可预测人类和犬类的心脏发病率和死亡率。实时三维超声心动图（3DE）可能可用于可靠评估马的左心房容积（LAV）。
确定 3DE-LAV 的观察者内和观察者间可重复性估计值，并将其与 2DE-LAV 估计值进行比较。
方法比较。
从 40 匹马中获得 3DE 数据集，然后对其质量进行分级，最终研究人群为 22 匹马。使用（a）半自动表面识别算法和（b）改良的 Simpson 圆盘法，从同一次 3D 数据集上四次测量 3DE 和 2DE 的最大 LAV（LAV ）和最小 LAV（LAV ），并计算左心房排空容积（LA EV）和左心房射血分数（LA EF）。由第二位观察者重复 3DE LAV 测量。
对于 3DE，观察者 1 的中位数 LAV 为 596cm，观察者 2 的中位数 LAV 为 852cm；观察者 1 的中位数 LAV 为 373cm，观察者 2 的中位数 LAV 为 533cm。LAV 和 LAV 的观察者内测量变异性较低，两位观察者的马水平内组相关系数（ICC）在 76%至 85%之间（马作为随机效应添加）。平均测量时，观察者间 ICC 为 58%（观察者作为随机效应添加），观察者间 ICC 为 50%（观察者作为随机效应添加），表明观察者之间存在一致差异。虽然 2DE LAV 测量的观察者内变异性相似，但 LAV 的变异性更大（ICC = 67%）。3DE 与 2DE 的方法间 ICC 较低，LAV 为 14%，LAV 为 0%左右，表明与方法的一致性差异较小。
研究人群小，观察者数量少，使用不同的成像方式（基频和倍频程谐波）。
3DE 评估 LAV 是可靠的，这表明其适合于临床病例的纵向评估。临床医生应注意观察者之间 LAV 测量值的差异。更明确的测量指南可能会提高可重复性。
