European Journal of Cardio-Thoracic Surgery Advance Access published May 28, 2014
Repair of tetralogy of Fallot—how much can we achieve with a single operation? Olivier Gheza,*, Konstantinos Dimopoulosa, Sonya V. Babu-Narayana,b,c and Michael Gatzoulisa,b,c a b c
Royal Brompton and Harefield NHS Foundation Trust, London, UK National Heart and Lung Institute, Imperial College London, London, UK NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College London
* Corresponding author. Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK. Tel: +44-20-73518550; fax: +44-20-73518214; e-mail: [email protected] (O. Ghez).
Keywords: Tetralogy of Fallot • Cardiac surgery • Long-term effects
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 subgroups. Event-free survival started diverging after 15 years from repair between the TAP and non-TAP subgroups, driven mainly by higher rates of pulmonary valve replacement (PVR). All but one case of PVR occurred in the TAP group but, as noted by the authors, patients requiring TAP repair are different from the remainder with less favourable RVOT and pulmonary artery anatomy; 15% of them, for example, required an initial palliative shunt compared with only 8% in the non-TAP group. Furthermore, the authors report no benefit of PVR on exercise capacity (data available for 11 of 49 PVR patients), or ventricular size (7 of 49 had magnetic resonance imaging (MRI) available). The comparison in this series of patients at the last follow-up that had undergone PVR to those that had not met criteria for PVR is limited by numbers and study design. The beneficial effects of PVR on reducing right ventricular volumes and improving functional capacity in patients with PR are well established [5]. However, as we gradually move towards a more proactive approach, PVR becomes a prognostic intervention, aimed at preserving RV function and preventing catastrophic events such as malignant arrhythmia and sudden cardiac death, and thus may not also be associated with significant improvement in exercise capacity or functional class [6]. We submit that a proactive approach towards maintaining/restoring haemodynamics in congenital heart disease, whether at presentation in early childhood or later on during adolescence or adulthood constitutes the mainstay of therapy. There is, currently, consensus towards limiting PR due to the now well-documented, late deleterious effects. This may be at the expense of reintervention for residual/recurrent RVOT obstruction as shown by the current and previous studies [1, 7]. In a recent, large multicentre study assessing long-term outcomes in repaired TOF, cardiovascular magnetic resonance derived increased RV mass-to-volume ratio decreased left ventricular and RV ejection fraction, and previous history of atrial tachyarrythmia predicted sustained ventricular tachycardia and death [8]. These data suggest that long-term RV pressure overload is also deleterious in the long term and should be avoided. In the present series, reported by Luijten et al., around 70% of all patients after TA/TP repair had residual gradients across the RVOT. The authors’ inclusive cut-off
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
CONGENITAL
EDITORIAL COMMENT
European Journal of Cardio-Thoracic Surgery (2014) 1–2 doi:10.1093/ejcts/ezu218
2
L.W.G. Luijten et al. / European Journal of Cardio-Thoracic Surgery
for RVOT obstruction (≥16 mmHg) implies some patients with potentially clinically acceptable residual gradients (
Repair of tetralogy of Fallot—how much can we achieve with a single operation? Olivier Gheza,*, Konstantinos Dimopoulosa, Sonya V. Babu-Narayana,b,c and Michael Gatzoulisa,b,c a b c
Royal Brompton and Harefield NHS Foundation Trust, London, UK National Heart and Lung Institute, Imperial College London, London, UK NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College London
* Corresponding author. Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK. Tel: +44-20-73518550; fax: +44-20-73518214; e-mail: [email protected] (O. Ghez).
Keywords: Tetralogy of Fallot • Cardiac surgery • Long-term effects
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 subgroups. Event-free survival started diverging after 15 years from repair between the TAP and non-TAP subgroups, driven mainly by higher rates of pulmonary valve replacement (PVR). All but one case of PVR occurred in the TAP group but, as noted by the authors, patients requiring TAP repair are different from the remainder with less favourable RVOT and pulmonary artery anatomy; 15% of them, for example, required an initial palliative shunt compared with only 8% in the non-TAP group. Furthermore, the authors report no benefit of PVR on exercise capacity (data available for 11 of 49 PVR patients), or ventricular size (7 of 49 had magnetic resonance imaging (MRI) available). The comparison in this series of patients at the last follow-up that had undergone PVR to those that had not met criteria for PVR is limited by numbers and study design. The beneficial effects of PVR on reducing right ventricular volumes and improving functional capacity in patients with PR are well established [5]. However, as we gradually move towards a more proactive approach, PVR becomes a prognostic intervention, aimed at preserving RV function and preventing catastrophic events such as malignant arrhythmia and sudden cardiac death, and thus may not also be associated with significant improvement in exercise capacity or functional class [6]. We submit that a proactive approach towards maintaining/restoring haemodynamics in congenital heart disease, whether at presentation in early childhood or later on during adolescence or adulthood constitutes the mainstay of therapy. There is, currently, consensus towards limiting PR due to the now well-documented, late deleterious effects. This may be at the expense of reintervention for residual/recurrent RVOT obstruction as shown by the current and previous studies [1, 7]. In a recent, large multicentre study assessing long-term outcomes in repaired TOF, cardiovascular magnetic resonance derived increased RV mass-to-volume ratio decreased left ventricular and RV ejection fraction, and previous history of atrial tachyarrythmia predicted sustained ventricular tachycardia and death [8]. These data suggest that long-term RV pressure overload is also deleterious in the long term and should be avoided. In the present series, reported by Luijten et al., around 70% of all patients after TA/TP repair had residual gradients across the RVOT. The authors’ inclusive cut-off
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
CONGENITAL
EDITORIAL COMMENT
European Journal of Cardio-Thoracic Surgery (2014) 1–2 doi:10.1093/ejcts/ezu218
2
L.W.G. Luijten et al. / European Journal of Cardio-Thoracic Surgery
for RVOT obstruction (≥16 mmHg) implies some patients with potentially clinically acceptable residual gradients (
