Assessment of right heart hemodynamics by contrast echocardiography

We studied inferior vena cava contrast echocardiography after upper extremity injection in 70 subjects; 59 were patients and 11 were controls. Inferior vena cava contrast was seen in 35 patients and in 1 control. "A-wave synchronous pattern" of contrast appearance was observed in 13 patients and 1 normal subject. The pattern did not depend upon the height of right atrial a-wave pressure or the right ventricular (RV) end-diastolic pressure, but was related to the respiratory cycle. A "random pattern" of contrast appearance was seen in 3 patients with cardiac arrhythmia and normal right heart hemodynamics. One patient with ventricular premature beats showed both "a-wave synchronous" and "random" patterns. A "v-wave synchronous pattern" was found in 20 patients, of which 17 had tricuspid regurgitation. Persistence of inferior vena cava contrast correlated with the height of right atrial v-wave (r = 0.87, p less than 0.001) and the severity of tricuspid regurgitation estimated from RV cineangiography. The differences of RV systolic pressure and echocardiographic right ventricular dimension between the study patients with and without tricuspid regurgitation did not reach statistical significance. We conclude: the echocardiographic RV dimension and the degree of RV hypertension are not predictors for the presence of tricuspid regurgitation and its severity; inferior vena cava contrast echocardiography may be used to estimate the severity of tricuspid regurgitation.