Reef V B
Department of Clinical Studies (Section of Sports Medicine and Imaging), New Bolton Center, University of Pennsylvania, Kennett Square 19348, USA.
Equine Vet J Suppl. 1995 Sep(19):71-80. doi: 10.1111/j.2042-3306.1995.tb04992.x.
Physiological flow murmurs occur frequently in horses and may be difficult to distinguish from murmurs associated with underlying cardiac disease. The significance of heart murmurs auscultated in horses is often difficult to determine if the horse is not exhibiting any clinical signs or if the signs, such as poor performance, are nonspecific. A complete echocardiographic examination (M-mode, 2-dimensional (2-D) and Doppler) provides an objective assessment of the severity of the horse's underlying cardiac disease. Valvular regurgitation and ventricular septal defects (VSDs) occur frequently and may impair performance, result in the horse's premature demise or have no apparent effect on the horse's life expectancy or performance capabilities. The echocardiographic findings that are used to formulate a prognosis for longevity and performance in horses with valvular regurgitation include the abnormalities detected on the valve leaflets, degree of cardiac chamber enlargement, severity of the resultant volume overload, size of the regurgitant jet, and relative relationship of jet size to chamber size. The echocardiographic findings that are used to formulate a prognosis for horses with VSDs are the number, size and location of the defect(s), degree of left ventricular volume overload, maximal velocity and direction of shunt flow through the defect and the presence and severity of concurrent valvulus regurgitation. Knowledge of the natural progression of the common types of cardiovascular disease in horses, coupled with the echocardiographic findings, clinical history and owner's or trainer's expectations can help the veterinarian form an accurate prognosis for life and performance in horses with heart murmurs.
生理性血流杂音在马匹中很常见，可能难以与潜在心脏病相关的杂音区分开来。如果马匹没有表现出任何临床症状，或者诸如性能不佳等症状不具有特异性，那么听诊到的心脏杂音的意义通常很难确定。完整的超声心动图检查（M型、二维（2-D）和多普勒）可对马匹潜在心脏病的严重程度进行客观评估。瓣膜反流和室间隔缺损（VSD）很常见，可能会影响性能，导致马匹过早死亡，或者对马匹的预期寿命或性能能力没有明显影响。用于对患有瓣膜反流的马匹的寿命和性能制定预后的超声心动图检查结果包括在瓣膜小叶上检测到的异常、心腔扩大程度、由此产生的容量超负荷的严重程度、反流束的大小以及反流束大小与心腔大小的相对关系。用于对患有室间隔缺损的马匹制定预后的超声心动图检查结果是缺损的数量、大小和位置、左心室容量超负荷的程度、通过缺损的分流血流的最大速度和方向以及并发瓣膜反流的存在和严重程度。了解马匹常见心血管疾病类型的自然进展，结合超声心动图检查结果、临床病史以及主人或训练师的期望，有助于兽医对有心脏杂音的马匹的生命和性能做出准确的预后判断。
