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Repair of tetralogy of Fallot-how much can we achieve with a single operation?

Patients with tetralogy of Fallot (TOF) are the beneficiaries of enormous progress made since the introduction of the Blalock– Taussig shunt in 1945. We nowadays expect near-normal life expectancy and excellent quality of life for many patients undergoing repair. However, this is purely speculative, as the first cohorts of patients with TOF who underwent repair between the 1960s and 1980s are still affected by late complications, namely pulmonary regurgitation (PR), exercise intolerance, ventricular dysfunction, clinical arrhythmias and premature death. While the reduction in perioperative risk to less than 1% is a major advance since the early days of TOF repair, there is still limited information on very long-term risks, particularly in patients born after the 1980s. We know, for example that malignant arrhythmias occur mainly after 20 years [1]. Central to improvement of late outcomes in TOF is preservation of ventricular function and prevention of clinical arrhythmias and sudden cardiac death. The operative techniques have evolved to reduce the impact of reparative surgery on right ventricular (RV) function, by avoiding extensive ventriculotomies and long-term volume and/or pressure ventricular overload from PR and/or pulmonary stenosis (PS). The technique of early transatrial, transpulmonary approach (TA/TP) for repair is preferred by many over the early era transventricular approach [2]. Early TA/TP allows adequate relief of right ventricular outflow tract (RVOT) obstruction with a more limited infundibulotomy, if any, and preservation of pulmonary valve function in selected cases. The anatomical spectrum of the RVOT, including the pulmonary valve and annulus, and of the main and proximal pulmonary arteries in TOF is highly variable necessitating tailoring of the surgical technique to the individual patient’s anatomy. Accordingly, a transannular patch (TAP) may be unavoidable in patients with a very restrictive and small RVOT/pulmonary valve annulus although the days of routine and large TAPs, predisposing patients to the deleterious long-term effects of free PR are well over [3]. Luijten et al. [4] in their article ‘Long-term outcome of transatrial— trans-pulmonary repair of TOF’ present data on their long-term experience. Mortality was low, both in the early perioperative period and in the long term (up to 20–25 years of follow-up). This is reassuring and consistent with the expectations and reaffirming of the role of a TA/TP approach. Morbidity, however, was substantial for all patients in the first 10 years after repair, relating mainly to interventions for RVOT obstruction in both TAP and non-TAP sub