This child has a well-functioning valve prosthesis for congenital mitral valve prolapse. The flow is now 1.7 m/s, and there is no regurgitation. Several ectopic atrial beats are heard, and now bigeminy. The snapping closing sound of the valve prosthesis is heard very clearly when the contraction of the ventricle is followed by rapid, premature closure of the atrioventricular valves. Age 10.2 years. Area of auscultation: left third ic (LIC3)