Heart sounds are best auscultated over the lower lateral thoracic wall between the 4th-5th intercostal spaces, typically where the elbow crosses the chest wall when the forelimb is pulled caudally (See Figure 17).
Figure 17. Heart Sounds Location.
Figure 17 shows optimal location for auscultation of the heart sounds and palpation of the heartbeat, in the 4th-6th intercostal space just above the sternum and just caudal to the elbow.