Severe pulmonary regurgitation late after total repair of tetralogy of Fallot: surgical considerations

After total repair of tetralogy of Fallot (TOF-R) with transannular patching (TAP), severe pulmonary regurgitation (PR) is reported to develop in up to 30% of patients at a follow-up of 20 years, and 10-15% or more need pulmonary valve replacement (PVR). In this study, time-related progression of PR and right ventricular (RV) dilatation, and functional recovery of the RV after PVR are analyzed, and the possible causes of PR and timing of PVR are discussed. Eighteen patients, who late after TOF-R with TAP underwent PVR for severe PR, were chosen for the study. NYHA class, QRS duration, RV dilatation index (RVDI = RVEDD/LVEDD), and RV-distal pulmonary artery (PA) peak systolic gradient were reviewed and retrospectively analyzed. TOF-R was performed at a mean age of 5.1 +/- 3.9 years (range: 0.6-12.8 years); the mean time interval from TOF-R to PR grade 3 onset was 11.8 +/- 7.0 years (range: 3.3-27.4 years), and from TOF-R to PVR was 18.5 +/- 7.8 years (range: 8.7-37.1 years). At PVR, 11 patients were in NYHA class II-III, all patients had severe PR (grade 3/3) and severe RV enlargement, 4 patients had ventricular arrhythmias, 7 patients significant distal pulmonary artery stenosis, and 2 patients small nonrelevant residual VSD. The mean preoperative RVDI (normal: 0.5) was 0.99 +/- 0.14 (range: 0.75-1.3), the mean QRS duration 170 +/- 24 ms (140-220 ms), and the mean RV-distal PA peak systolic pressure gradient 33.3 +/- 19.0 mmHg (range: 10-60 mmHg). Patients aged at TOF-R> 5 years had considerably longer redo-free intervals than their younger counterparts: mean 23.1 years (range 8.7-37.1 years) vs 14.8 years (range: 9.3-21.2 years), respectively. The redo-free intervals and the duration of severe PR correlated inversely with the RV-PA gradient. At a mean follow-up of 1.3 years (2 weeks-5 years), the mean RVDI decreased from 0.99 +/- 0.14 to 0.69 +/- 0.15, the mean validity class improved from 2.5 to 1.1. One patient died. After TOF-R with TAP, the progression of PR has very individual dynamics, resulting in extremely varying redo-free intervals. Concomitant pulmonary stenosis seems to exaggerate progression of PR. PVR results in effective reduction of diastolic dimensions of severely dilated RV and in improvement of validity class. Referred PVR in no-risk cases seems to be justified.