Anomalies of the Superior Vena Caval Flow Pattern in Patients with Tricuspid Insufficiency

An intra-operative method, based on simultaneous superior vena caval (SVC) flow pattern recording and right atrial and ventricular pressure registrations, has been used in 20 cases of tricuspid insufficiency (TI), of which 19 accompanied mitral and aortic/mitral valve disease. The method detects TI easily and provides quantitative information about TI. According to the flow tracings, TI has been classified in three groups: Severe TI = SVC reflux 30%; moderate TI=15% > SVC reflux > 30%; and slight TI = SVC reflux > 15%. A characteristic flow profile was found in the group with severe SVC reflux. The flowmetric findings correlate well with the cine-angiographical classification of TI. The mean values of right atrial and ventricular pressures were significantly higher than normal, but there was no correlation between the percentage of reversed flow and pressures, except in the cases with slight reflux. Flow measurements were also performed with advantage after extra-corporeal bypass in cases undergoing tricuspid valve replacement and annuloplasty. The method provides more reliable and accurate information about the tricuspid valve function than do the conventional examinations. This method should make it easier to compare the results of various surgical and conservative treatments of different degrees of TI.