Typical patent ductus arteriosus – Pulses are bounding, and pulse pressure is widened due to diastolic runol through the ductus. S₁ is normal and S₂ is usually narrowl split. In large shunts, S₂ may have a paradoxical split (ie, S closes on inspiration and splits on expiration). Paradoxica splitting is caused by volume overload of the LV and prolonged ejection of blood from this chamber.