Sudden death in adults with repaired coarctation of the aorta: A case for sex-based risk factors

Background: Sudden cardiac death (SCD) is an important risk for adults with repaired coarctation of the aorta (rCoA). We aimed determine if there are clinical risk factors for SCD in adults with rCoA. Methods and results: SCD events and clinical data from all adults with rCoA at a tertiary care center (2007–2017) were evaluated. In 167 adults with rCoA (39 ± 11 years old, 75 (45%) female) SCD occurred in 8 (5%) (vs. age-matched adults 0.9%). Those with SCD demonstrated significant QTc prolongation (QTc: 479 ± 16 vs. 434 ± 30 msec, p < 0.001). Overall, adults with rCoA and a prolonged sex-normative QTc interval had a 12-fold increased risk of SCD (ᵡ² (1) = 12.3, p < 0.001), with men sustaining SCD at younger ages (42 ± 13 years vs. women 60 ± 10 years, p < 0.05). Multiple logistic regression modeling demonstrated that prolonged QTc selectively advanced risk for SCD in men only (ᵡ² QTc prolongation 8.46, p < 0.005 and ᵡ² age 0.29, p = 0.587), whereas in women, age was associated with SCD risk (ᵡ² QTc prolongation 2.84, p = 0.092 and ᵡ² age 7.81, p = 0.005). Non-sustained ventricular tachycardia, ventricular dysfunction, and myocardial fibrosis did not significantly impact SCD risk. Conclusions: There is an unanticipated high burden of SCD in adults with rCoA, occurring in men at younger age than women, suspicious for primary electrophysiologic dysfunction. Future investigation of sex-specific SCD risk in rCoA is important to better understand this disease and its late phenotype.