Thoracic Aortic Dissection in Tetralogy of Fallot: A Review of the National Inpatient Sample Database

Background: Thoracic aortic aneurysm is common in patients with tetralogy of Fallot (TOF); the incidence of thoracic aortic dissection (TAD) is unknown, but generally considered to be uncommon. The purpose of this study was to determine incidence and risk factors for TAD in TOF patients. Methods and Results: This work is a retrospective review of the National Inpatient Sample (NIS) database for cases of ascending TAD among all hospital admissions in adults with TOF, 2000–2014. Of 18 353 admissions in TOF patients, 11 (0.06%; 6 per 10 000 admissions) of these were TAD-related admissions. For the TAD-related admissions, mean age was 49.8±7.2 years; aortic surgical interventions were performed during 8 of the admissions, and overall in-hospital mortality was 45% (5 of 11). Risk factors associated with TAD-related admission were age >60 years (odds ratio, 2.41; 95% CI, 1.23–3.25; P=0.013), male sex (odds ratio, 6.91; 95% CI, 4.85–8.54; P<0.001), and hypertension (odds ratio, 1.74; 95% CI, 1.06–3.19; P=0.037). Conclusions: This is the first population-based study of TAD outcomes in patients with TOF, and it showed a low risk of TAD in this population. This has important clinical implication with regard to surveillance and surgical intervention. Given that prevalence of thoracic aortic aneurysm is higher in TOF patients compared with the general population; therefore, making clinical decisions based on outcomes data and practice guidelines derived from patients with degenerative and bicuspid aortic valve–related aortopathies may lead to overtreatment. Further studies are required to better understand the pathobiology of this disease in order to make evidence-based recommendations for surveillance and treatment.