Background

Echocardiographic assessment of diastolic function in the setting of Fontan physiology is not well validated. We recently demonstrated that atrioventricular systolic to diastolic duration ratio (AVV S/D ratio) independently predicts mortality in Fontan-adults and that a value >1.1 was associated with poor prognosis.
Purpose

To correlate echocardiographic measures of diastolic function with direct measurement of ventricular end-diastolic pressure (VEDP).
Methods

A retrospective analysis was undertaken of Fontan-adults who had transthoracic echocardiography (TTE) within 12 months of direct measurement of VEDP during cardiac catheterisation.
Results

Fifteen Fontan adults (3 males, mean age 29 ± 9 years) were evaluated. Thirteen patients had dominant morphologic left ventricle and 2 had morphologic right ventricle. Four had atriopulmonary connection and 11 had total cavopulmonary connection. Twelve patients were NYHA Class I/II and 3 were Class III. Time between TTE and cardiac catheter was 46 ± 113 days; VEDP was 8 ± 5 mmHg. Ten patients had preserved ventricular function, 3 had mild and 2 had moderate systolic impairment by subjective TTE assessment. AVV S/D ratio had the strongest correlation with VEDP (r = 0.8, p = 0.001). AVV S/D ratio ≥ 1.1 had 100% positive predictive value and 92% negative predictive value for detecting VEDP >10 mmHg. The only conventional echocardiographic measure of diastolic function that correlated with VEDP was pulmonary vein A wave - atrioventricular A wave duration difference (r = 0.8, p = 0.02).
Conclusions

TTE measures reflect VEDP in adults with a Fontan circulation. AVV S/D ratio is a simple parameter yet to enter standard practice that can be used to identify elevated VEDP.