Long-term outcomes of tetralogy of fallot in the Kingdom of Bahrain

Abstract

Introduction: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Surgical correction has improved survival but re-intervention is often required. Objectives: The objective is to assess outcomes after surgical repair of TOF, long-term follow-up, and factors that influence these results. Materials and Methods: This is a retrospective study conducted in a tertiary care center. Records of patients diagnosed with TOF from 1992 to 2019 (37 years) were retrieved from a detailed database. Patients who underwent complete correction were grouped according to diagnosis, the technique utilized in surgical repair, need for staged repair, and syndromic association. Univariate actuarial and event-free survival analysis was performed. The endpoint for an event was death or re-intervention. Results: A total of 230 patients were diagnosed with TOF and 174 patients underwent complete surgical repair. At 40 years postoperatively, survival was 96%. Actuarial survival was independent of syndromic associations, anatomical diagnosis, type of surgery, or previous shunt. Event-free survival (EFS) survival was 8.12%. EFS was significantly worse for patients with pulmonary atresia (PA) (Hazard ratio, 4.1125; 95% confidence interval [CI], 1.2654–13.3657; P < 0.0001) and for those that required homograft/conduit. The median duration for EFS was 22.73 years, 19.58 years, and 9.12 years for transannular patch (TAP), pulmonary valve-sparing (PVS), and homograft group, respectively. The survival curve for the PVS group merged with that of TAP 20 years postoperatively. Similarly, it merged at 22 years for staged versus primary repair and at 22.73 years for syndromic versus nonsyndromic patients. A weak correlation was found between age at surgery and event-free duration (cc, 0.309; P < 0.0001). The need for TAP was not influenced by the previous palliation, χ2 (1, n = 154) = 3.36, P = 0.0667, or with interval to complete correction after the shunt procedure (P = 0.9672). Conclusions: Total correction of TOF has low perioperative mortality and good long-term survival, but the need for re-interventions is high. This study demonstrated that patients requiring homograft/conduit and those with a diagnosis of PA had worse outcomes. Comparison between different surgical groups showed merging of survival curves in follow-up that signifies gradual loss of survival advantage over time.

Keywords

• follow-up
• survival analysis
• tetralogy of fallot