Detection of Tricuspid Valvular Regurgitation with a Catheter Velocitometer
The preoperative diagnosis of tricuspid valvular regurgitation (TVR) is unreliable, and definitive diagnosis is usually made by the surgeon at the time of operation. In preliminary studies of a new electromagnetic catheter velocitometer used in dogs undergoing thoracotomy, pressures in the right atrium and ventricle were recorded simultaneously with the velocity of vena caval blood flow through a competent tricuspid valve and following surgical production of TVR. Normal and chronic TVR dogs were studied by catheterization. A systolic to diastolic (S/D) ratio was derived by measuring the areas beneath the recorded vena caval velocity curves that coincided with ventricular systole and diastole. In both normal and TVR dogs, heart rate varied from 60 to 240/min, and mean right atrial pressure varied from 2.5 to 15 mm Hg. Results indicated that patterns of velocity clearly distinguished normal from regurgitant tricuspid valves; velocity pattern of TVR was the reciprocal of the normal pattern; vena caval S/D ratio in normal animals was 2.0 ± 0.3 but never less than 1.0, and S/D ratio in TVR was 0.6 ± 0.15 but always less than 1.0. Under conditions similar to clinical cardiac catheterization, the patterns of velocity and the S/D ratio obtained with the velocitometer provided a highly reliable assessment of the presence or absence of TVR in dogs.
- © 1971 American Heart Association, Inc.