fig2

Figure 2. In valvar pulmonary stenosis, the degree of pulmonary valve obstruction may be predicted by auscultatory findings. In mild obstruction (top), the ejection click (EC) is evidently separated from the first heart sound (S₁), the murmur begins with the click, peaks in early systole, and stops way before the aortic component of the second heart sound (A₂), and the pulmonary component of the second heart sound (P₂) is normal to increased in intensity. In moderate pulmonary stenosis (middle), the click is closer to the first heart sound, the ejection murmur peaks later in the systole and the murmur reaches the A₂, and the second heart sound is widely split with a soft pulmonary component. In severe valvar stenosis (bottom), the click is either not present or occurs so close to S₁ that it cannot be auscultated separately. The murmur peaks late in systole and extends beyond the A₂. The second heart sound is widely split with an extremely soft or inaudible P₂. Modified from Rao^[5].