Follow-up
Median follow up time after correction was 19 years (range 1 to 27 years). Overall survival after definitive correction was 96% at 20 years (Figure 2). One patient died four years after successful correction of unknown cause, probably of cardiac arrhythmia. Two patients died 20 years after correction due to progressive heart failure. Two of these had 22q11 deletion. From the survivors all but one are in NYHA class I or II. Four of the seven patients who were not suitable for correction died. One patient died 2 years after the last unifocalization due to respiratory failure and infection. One patient died of unknown cause 9 years after the last unifocalization procedure. One patient died 14 years after the last unifocalization of multi-organ failure and sepsis and one patient died of massive intracranial bleeding 9 years after the last unifocalization.
Among the 5 survivors with 22q11 deletion, one is awaiting correction, one is palliated in a reasonable condition, 3 had a definitive correction (one in reasonable condition and 2 in good condition). The overall survival in the 22q11 deletion patient was significantly (p=0.041) lower compared to non-syndromic patients, (5 out of 10 (50%)) versus 25 out of 29 (67%) respectively).
Pulmonary valve replacement
After final correction in 21 patients other interventions were performed. They are listed in Table 1 and consist mostly of pulmonary valve replacement either surgically or percutaneously and dilatation or stenting of pulmonary branches. The modified Blalock Taussig shunt mentioned in the Table was placed in a patient with stenosis of a hypoplastic left pulmonary artery. Freedom from pulmonary valve replacement was 88%, 73%, 60% and 27%% at 5, 10, 15 and 20 years respectively (Figure 3).
Echocardiography
Echocardiographic data after correction at the last check, showed in 18 patients (75%) a reasonable or good right ventricular function (RVF). Four patients (17%) had a moderate RVF. Only 2 patients (8%) had a severely impaired RVF.
The tricuspid regurgitation was trivial, mild, and moderate in 10 (42%), 10 (42%) and 4 patients (16%), respectively. The pulmonary regurgitation was absent/trivial, mild, moderate or severe in 6 (26%), 8 (35%), 6 (26%) and 3 (13%), respectively. The right ventricular dilatation was absent, mild, moderate and severe in 2 (8%), 4(17%), 12 (50%) and 6 (25%), respectively. If measurable, the median right ventricular (RV) pressure was estimated at median of 54 (25-108) mmHg. The median estimated pressure across the homograft is 19 (7-49) mmHg. Inherent thereto, the calculated pressure differences of 32 (0-95) mmHg suggests increased pulmonary artery pressures.
In 7 patients a small residual VSD was present, without hemodynamic significance in terms of flow.
MR imaging
From 17 patients after correction we obtained detailed MR imaging with a median interval between correction and MR image of 15,6 years (range 9-22 years). Based on the calculations the median right ventricular ejection fraction (RVEF) was 44% (range 13-62%), the median left ventricular ejection fraction (LVEF) was 52% (range 29-64%), the median RV end diastolic volume was 190 ml (range 94-339 ml), indexed 105 ml/m2 (range 76-176 ml/m2) and the median pulmonary regurgitation fraction was 19% (range 0-50%).