Echocardiographic assessment of atrial properties in single ventricles vs. normal controls.

INTRODUCTION: Atrial function is increasingly being recognized as a significant factor in overall cardiac function in adults. Limited studies evaluating atrial properties exist in the pediatric congenital heart disease population. The goal of this study was to evaluate atrial properties in patients with single ventricle physiology after Fontan completion and compare these values with normal control patients. METHODS: Echocardiograms were performed in patients with single ventricular physiology and in control patients. Tissue Doppler and blood flow measurements were obtained. Atrial fraction and atrial electromechanical values were calculated. Differences were assessed with one-way analysis of variance. Post hoc comparisons were performed with Tukey adjustment. P < .05 was considered significant. RESULTS: No significant difference was present in age or heart rate between single ventricle and control patients. The single right ventricle tricuspid valve A wave (52.6 ± 14.5 vs. 36.7 ± 10.4 cm/s) and atrial fraction (39.2 ± 6.2 vs. 32.7 ± 7.7%) were significantly higher, and the E/A ratio (1.4 + 0.3 vs. 1.8 + 0.4), tricuspid valve E/A velocity-time integral (1.6 + 0.4 vs. 2.2 + 0.7 cm), and late diastolic annular value (5.3 + 1.5 vs. 8.7 + 1.4 cm/s) were significantly lower compared with the controls. The single left ventricle late diastolic annular velocity (4.2 + 1.0 vs. 6.7 + 1.3 cm/s) was significantly lower and atrial fraction was significantly higher compared with the controls (37.7 ± 12.5 vs. 29.8 ± 4.3%). There were no significant differences in atrial electromechanical measurements between groups, but the single right ventricle patients tended to have increased atrial dyssynchrony compared with controls. CONCLUSIONS: Patients with single ventricle physiology after Fontan completion have differences in atrial properties when compared with normal controls. These differences may have important implications in their long-term outcomes. Further studies are necessary to determine the clinical significance of these findings.

Differences in tissue Doppler imaging between single ventricles after the fontan operation and normal controls.

Tissue Doppler imaging measurements could be used to quantitate ventricular function in patients with systemic single ventricles. The objective of the present study was to measure the tissue doppler imaging-derived indexes of function and dyssynchrony in patients with single ventricular physiology and compare these values with those from control patients. Echocardiograms were performed in patients with single left or right ventricular physiology and control patients. Measurements were made of the free walls at the level of the atrioventricular annulus. Differences were assessed with one-way analysis of variance. Post hoc comparisons were performed with a Tukey adjustment. No significant difference was present in age among the control (5.75 +/- 1.73 years, n = 16), single left ventricle (7.07 +/- 2.81 years, n = 12), or single right ventricle (6.25 +/- 2.2 years, n = 14) groups. The single right ventricular free wall peak systolic annular, peak early diastolic annular, and peak late diastolic annular velocities were significantly lower and the myocardial performance index and interval to mechanical activation greater compared to the controls. The single left ventricular free wall peak systolic annular, peak early diastolic annular, and peak late diastolic annular velocities were also significantly lower and the myocardial performance index and interval to mechanical activation greater compared to controls. In conclusion, significant decreases in systolic and diastolic function, as well as differences in dyssynchrony, using tissue Doppler imaging exist in patients with single ventricular physiology compared to control patients.

Two-dimensional speckle strain and dyssynchrony in single right ventricles versus normal right ventricles.

BACKGROUND: Patients with single-right ventricle (RV) physiology are at increased risk for myocardial dysfunction and mechanical dyssynchrony. Newer echocardiographic modalities may be better able to quantitate right ventricular function in this unique population. The aim of this study was to use two-dimensional speckle analysis of strain and strain rate to quantify systolic function and dyssynchrony in single-RV post-Fontan patients and compare them with values for controls. METHODS: Patients with single RV who underwent Fontan palliation and patients with normal biventricular anatomy were studied. Two-dimensional speckle echocardiography was used to measure strain, strain rate, time to peak, and longitudinal displacement in a 6-segment model of the RV. Independent t tests were used to compare group means. P values < .05 were considered significant. RESULTS: Thirteen patients were studied in each group. There was no significant difference in age between single-RV patients and controls (6.60 +/- 2.07 vs 5.75 +/- 1.83 years, respectively). Single-RV strain values were significantly lower in all 6 segments compared with values in controls (basal interventricular septum [IVS], -14.28 +/- 7.78% vs -22.00 +/- 2.36%; mid IVS, -17.70 +/- 4.54% vs -22.99 +/- 2.71%; apical IVS, -19.46 +/- 4.97% vs -25.42 +/- 4.06%; basal RV, -22.40 +/- 5.7% vs -41.42 +/- 5.42%; mid RV, -21.20 +/- 3.21% vs -39.67 +/- 6.04%; apical RV, -20.70 +/- 4.90% vs -33.68 +/- 3.90%). Systolic strain rate and longitudinal displacement were also lower in the free wall and apical IVS in single-RV patients compared with controls. The modified Yu index for strain time to peak was longer in the single-RV patients (43.16 +/- 13.63 vs 21.72 +/- 7.25 ms). CONCLUSION: Significant differences in strain analysis between single-RV patients and patients with biventricular physiology exist at a relatively young age. Future studies are needed to determine the clinical significance of these differences.