Diastolic rumbles with porcine heterograft prosthesis in the atrioventricular position. Normal or abnormal prosthesis?

Three patients with porcine atrioventricular valves (two mitral, one tricuspid) with diastolic rumbles and presystolic murmurs are presented. Full hemodynamic and angiographic studies demonstrated moderate to severe prosthetic stenosis, even in the one patient who was minimally symptomatic. Diastolic murmurs across atrioventricular porcine heterografts indicate prosthetic stenosis until proved otherwise by full hemodynamic and angiographic studies. If the studies indicate normal function of the device and calculated prosthetic valve area that is small for the patient, then it must be recognized that the device is hemodynamically "stenotic" for that particular patient (valve prosthesis--patient mismatch).