The purpose of this study is to evaluate the correlation between fluid volume status and right ventricular volume and function, in those with free pulmonary valve insufficiency after Tetralogy of Fallot (TOF) repair.

The purpose of this study is to measure the changes in Right Ventricular size and function with changes in preload, using cardiovascular magnetic resonance (CMR). Based on an intensive research and clinical observations the investigators hypothesize that changes in volume status cause a statistically significant difference in the Cardiovascular magnetic resonance (CMR) measured RV End Diastolic Volume (EDV), end-systolic volume (ESV), ejection fraction (EF) and pulmonary regurgitation (PR). The investigator hypothesizes that smaller changes will occur in left ventricular LV EDV, ESV, and EF.

1. To establish a correlation between the changes in preload volume status and RV size and function in patients with free pulmonary insufficiency (PI) after TOF repair using CMRI.
2. To assess the effects of preload status on the measured severity of pulmonary regurgitation (PR).
3. To assess the effects of preload status on the left ventricular (LV) size

This study will be conducted in compliance with this protocol, good clinical practice and the applicable regulatory requirements.

Inclusion Criteria:

1. TOF patients who have had repair using a transannular patch.
2. Patients that present with free pulmonary insufficiency.
3. Are older than 18 years.

Exclusion Criteria:

1. Patients who have lesions predisposing to chronic volume overload (i.e. patients with significant residual postoperative ventricular septal defects (VSD), or large aorto-pulmonary collaterals or more than moderate tricuspid insufficiency) since all these hemodynamic conditions can influence the late function of the right ventricle and potentially affect the response of the right side of the heart in changes in volume status

2. Patients who had a valve sparing TOF repair and have less than free pulmonary insufficiency.

3. Patients who have significant residual right-sided obstruction (i.e. patients who have residual RVOT obstruction or significant residual branch pulmonary artery stenosis), as it is shown that residual pulmonary stenosis may protect from RV dilation and from deterioration of the RV function.

4. Patients who cannot be reconstructed with a transannular patch and/or require a right ventricle to pulmonary artery homograft for reconstruction including:

   • pulmonary atresia and VSD
   • patients with anomalous coronary crossing the right ventricular outflow tract (RVOT) and
   • patients with TOF-absent pulmonary valve syndrome.

5. Patients with renal failure and renal insufficiency

6. Patients with uncompensated heart failure

7. Cancer patients

8. Latex allergic patients

9. Patients with diabetes

10. Pregnant females

11. Prisoners

12. Individuals who lack consent capacity