Physiologic valve regurgitation in normal cats.

The purpose of this study was to evaluate echocardiograms from normal cats for the presence of physiologic valve regurgitation (PVR). PVR occurs commonly in normal dogs, however, the percentage of normal cats with PVR has not been previously reported. Echocardiograms were retrospectively and prospectively evaluated from clinically normal cats without echocardiographic evidence of cardiac disease. PVR was diagnosed if the valve was structurally normal and regurgitant color flow was subjectively trivial. The color jet area was expressed as a percentage of the chamber area. Results are expressed as mean+/-SD. Retrospective study: The 46 cats were 2.1+/-1.5 years (range 0.3-7 years) and were purebred. Four cats (9%) had physiologic mitral regurgitation (PMR) (area of 4%). One cat (2%) had physiologic pulmonary regurgitation (PPR). Twenty-seven cats (57%) had physiologic tricuspid regurgitation (PTR) (area of 6+/-3% to 11+/-8% depending on view). Prospective study: The 58 cats were 4.9+/-2.8 years (range 1-12 years), weighed 5.2+/-1.2kg and were of various breeds. Three cats (5%) had PMR (area of 10+/-2%). One cat (2%) had PPR. Forty-one cats (71%) had PTR (area of 9+/-5% to 11+/-6% depending on view). Retrospective and prospective data were pooled (104 cats) and 7 cats (7%) had PMR, 2 cats (2%) had PPR and 68 cats (65%) had PTR. PTR is common in normal cats and the average regurgitant jet area is small compared to the chamber area.