What are some diseases that affect valvular function, and how can they be diagnosed with imaging?
The aortic, pulmonic, mitral, and tricuspid valves can become stenotic, incompetent, or both. A chamber draining through a stenotic valve experiences a pressure load; if this chamber is a ventricle, it responds with muscular hypertrophy. If this chamber is an atrium, however, it responds with enlargement. A chamber draining through an incompetent (regurgitant) valve experiences a volume load ( Figure 12-6 ) and responds with enlargement (whether it is an atrium or a ventricle). Echocardiography and MRI can measure chamber size and velocity and direction of blood flow across a valve orifice, detecting and quantifying valvular disease.