Doppler assessment of pulmonary artery flow patterns and ventricular function after the Fontan operation

To assess the relation between ventricular systolic and diastolic function and pulmonary artery (PA) flow patterns after the Fontan operation, 15 postoperative patients were prospectively evaluated with echocardiography. Blood flow velocities in the PA were recorded with pulsed Doppler echocardiography. Ejection fraction was measured by 2-dimensional echocardiography using Simpson's rule. Indexes of diastolic function were measured from the systemic atrioventricular valve inflow Doppler and included peak E and A velocities, peak filling rate normalized for stroke volume, the fractions of filling in early and late diastole (E and A area fractions), and the E/A velocity and area ratios. Compared with 15 age-matched control subjects, the 15 patients who had undergone the Fontan procedure had decreased peak E velocity (0.65 +/- 0.20 vs 0.87 +/- 0.10 m/s), decreased E/A velocity ratio (1.29 +/- 0.23 vs 1.98 +/- 0.46), decreased normalized peak filling rate (6.09 +/- 0.90 vs 6.81 +/- 0.83 s-1), decreased E area fraction (0.63 +/- 0.09 vs 0.72 +/- 0.07), increased A area fraction (0.37 +/- 0.07 vs 0.24 +/- 0.06), and decreased E/A area ratio (1.77 +/- 0.45 vs 3.33 +/- 1.15) (p less than 0.05). These diastolic filling abnormalities are consistent with impaired ventricular relaxation and decreased early diastolic transvalvular pressure gradient. PA Doppler recordings showed 2 distinct patterns of flow. Pattern I, observed in 9 patients, showed biphasic forward flow with peak velocities in mid to late systole and mid-diastole. Pattern II, observed in the remaining 6 patients, showed decreased systolic forward flow, a late systolic to early diastolic flow reversal, and delayed onset of diastolic forward flow.(ABSTRACT TRUNCATED AT 250 WORDS)