Risk factors for mortality and ventricular tachycardia in patients with repaired tetralogy of Fallot: a systematic review and meta-analysis

Abstract Background Patients with repaired tetralogy of Fallot (rTOF) have increased risk for mortality, sudden cardiac death and ventricular tachycardia (VT). The aim of this systematic review and meta-analysis was to offer an updated analysis of risk factors following significant changes in surgical and peri-operative management. Methods A meta-analysis based on the published literature between 2008 and 2018 was conducted. Endpoints were VT, cardiac mortality/VT, and all-cause mortality/VT. Studies with > 100 patients and > 10 events were included. Results Fifteen studies including 7218 patients (average age 27.5 years) were analyzed. Risk factors for VT included older age (per 1 year, OR 1.039; 95% CI 1.025–1.053), older age at corrective surgery (per 1 year, OR 1.034; CI 1.017–1.051), prior palliative shunt (OR 3.063; CI 1.525–6.151), number of thoracotomies (OR 1.416; CI 1.249–1.604), longer QRS duration (per 1 ms, OR 1.031; CI 1.008–1.055), and at least moderate right ventricular dysfunction (OR 2.160; CI 1.311–3.560). Additional risk factors for cardiac death/VT were prior ventriculotomy (OR 2.269; CI 1.226–4.198), lower left ventricular ejection fraction (per 1%, OR 1.049; CI 1.029–1.071), and higher right ventricular end diastolic volume (per 1 ml/m 2 , OR 1.009; CI 1.002–1.016). Supraventricular tachycardia/atrial fibrillation was an additional risk factor for all-cause mortality/VT (OR 1.939; CI 1.088–3.457). Conclusion The study highlights the importance of preservation of biventricular systolic function on late outcomes. Ventricular function appears to have a greater impact on outcomes than the severity of pulmonary regurgitation alone in this patient population.