Relationship between type of outflow tract repair and postoperative right ventricular diastolic physiology in tetralogy of Fallot - Implications for long-term outcome

Background Restrictive right ventricular (RV) physiology can be present early and late after tetralogy of Fallot repair. It is associated with a complicated early postoperative course but is favorable late after repair because it is associated with less pulmonary regurgitation, better exercise tolerance, and less QRS prolongation and symptomatic ventricular arrhythmias. It is not known, however, whether in the current surgical era, this physiology is present in tetralogy of Fallot patients at mid-term follow-up and whether it is related to the type of RV outflow tract repair. Finally, the impact of this physiology on the early evolution of QRS prolongation has not been examined previously. In this study we attempted to address these issues in a cohort of recently operated patients. Methods and Results Ninety-five patients were studied 4.3 years after repair by Doppler echocardiography, serial electrocardiograms, and chest radiographs. Restrictive RV physiology defined by the presence of antegrade pulmonary artery flow in late diastole was present in 38% of the patients. It was more common in patients with transannular patch (TAP) repair compared with non-TAP repair (50% versus 21%, P<.05). QRS duration at follow-up was 121.2+/-17.6 and 132.6+/-11.8 ms in restrictive and nonrestrictive patients with TAP repair, respectively (P<.02). Conclusions Restrictive RV physiology has been identified at mid-term follow-up in a contemporary surgical series. It is associated with less QRS prolongation, regardless of the technique used for outflow tract repair, and may be associated with fewer long-term complications. Nonrestrictive physiology is associated with the most marked QRS prolongation. This subgroup is most st risk from the late deleterious consequences of chronic pulmonary regurgitation.