# Distortion of valve cusps leads to mechanical effects which cause ineffective closure (incompetence), and distortion and enlargement of the valves by the thrombus mass causes narrowing of the valve outflow (stenosis). These effects lead to a progressive inefficiency of cardiac pumping and give rise to [[Venous Congestion and Hyperaemia - Pathology#Generalised (Systemic) Venous Congestion|general venous congestion]], [[Oedema - Pathology|oedema]] and circulatory failure. | # Distortion of valve cusps leads to mechanical effects which cause ineffective closure (incompetence), and distortion and enlargement of the valves by the thrombus mass causes narrowing of the valve outflow (stenosis). These effects lead to a progressive inefficiency of cardiac pumping and give rise to [[Venous Congestion and Hyperaemia - Pathology#Generalised (Systemic) Venous Congestion|general venous congestion]], [[Oedema - Pathology|oedema]] and circulatory failure. |