Clinical Investigations The Influence of the Fontan Operation on Ventricular Systolic Functions in Patients With Single Ventricle

The systolic function parameters of the ventricle were evaluated echocardiographically in the patients with functionally single ventricle. Three groups, 10 patients (group II) aged 4.77±3.48 years having no operation, 12 patients (group III) between 12.34± 11 . 18 years of age with systemic-pulmonary artery shunt and 2 1 patients performed Fontan operation aged 11.32±6.79 years constituted our study population. At the mean age of 6.56±2.87 years, 21 children having no cardiac disease have been accepted as the control group. In the evaluation of the systolic ventricular function, maximal and mean velocity and velocity-time integral of the aortic flow, shortening and ejection fractions (SF, EF) of the main ventricular chamber , heart rate adjusted shortening and ejection fraction (SFc, EFc) of the ventricle were determined. The maximal and mean velocity-time integrals of the aortic flow were smaller in the group IV patients. No difference was determined for those parameters between that of groups II and III and of the control group. SF was smaller in the patients with single ventricle than those for control group, but it was statistically significant for the group II and III patients, while it was not for the Fontan operation group. EF was not different between patients and the control group. Both SF and EF were smaller in the patients with systemic-pulmonary shunt. SFc was smaller than 1 that was accepted as a limit for normal, only in the patients with systemic-pulmo- nary shunt. EFc was not different in the patients with single ventricle and control group except the patients with systemic-pulmonary shunt, those having the smallest values. In patients with systemic-pumonary shunt the postoperative period being either less or more than three years did not make much difference in terms of the parameters. Neither postoperative follow-up period of above or below three years, nor operative age of above or below eight years influenced significantly parameters in patients who had undergone the Fontan operation. In conclusion; we decided that because the ranges of normal aortic flow velocities were so large, they were not available for the evaluation of the systolic functions. The patients with single ventricle performed Fontan operations have better systolic functions than those not operated. SF and EF that were used usually in the echocardiographic examination , were sufficient for the evaluation of the systolic function and were closely related with the other parameters. In the patients with single ventricle, after mean of 2.35 years following Fontan operation there were no systolic dysfunction, disregarding same exceptions.