Objective : In tetralogy of Fallot, transannular patching is suspected to be responsible for late symptomatic dilatation of the right ventricle (RV). We retrospectively reviewed our policy of preserving the pulmonary annulus by limiting the incision to the RV.
Methods : We reviewed 191 consecutive pts who had a tetralogy of Fallot repair between 1964 and 1984. A transannular patch was used in 99 pts (52%) while 35 had a patch closure of the RV. Two pts had a transatrial-transpulmonary approach. All pts were offered a follow-up consult. To identify which preoperative and operative variables would be predictive of an adverse long-term outcome related to progressive right ventricular dilatation, the following adverse events were investigated: cardiac death, reoperation for symptomatic RV dilatation and NYHA class II or III. Independent contributions to prognosis were assessed with Cox regression.
Results : Follow-up was 95% complete after a mean of 22 ± 5 years. The 30-year actuarial survival was 86 ± 5%. The 30-year freedom from all adverse events was 61 ± 8% in pts who had no RV patch, 32 ± 6% in pts who had a RV patch and 24 ± 9% in those with a transannular patch. By multivariate Cox regression, RV patching, whether transannular or not, was the most significant independent predictor of late adverse events (improvement X2 = l6.6; p < 0.001). In pts who had a repair without patching, the ratio between end-diastolic dimensions of RV and LV evaluated in short axis was smaller ( 0.61 ± 0.017 vs. 0.75 ± 0.23; p = 0.007) and there was less pts with severe pulmonary insufficiency (9% vs. 40%, p = 0.005). There was no difference between pts with RV patch or transannular patch concerning late outcome (log rank test = 0.6) and RV size (0.70 ± 0.28 vs. 0.76 ± 0.26; p = 0.4) or number of pts with severe pulmonary insufficiency (30% vs 43%; p = 0.3).
Conclusion : In our experience of repair of tetralogy of Fallot, limiting the incision to the RV does not achieve better long-term results than transannular patching: both are responsible for a similar degree of long-term pulmonary insufficiency, right ventricular dilatation and limited exercise performance.