Short- and Mid-Term Autograft Outcomes Following the Reinforced Ross Operation

Background The Ross operation for aortic valve replacement continues to be a controversial option because of concerns related to late autograft dilation and progressive neo-aortic insufficiency. In 2005, the reinforced Ross procedure was described at our institution to address this problem. We aim to analyze the short and mid-term outcomes following this procedure. Methods This is a retrospective study of patients who underwent the reinforced Ross operation between 2004 and 2019. A comprehensive chart review was performed. Echocardiograms were independently reviewed by an adult congenital cardiologist. The time to reintervention was evaluated with a Kaplan-Meier curve. Analysis was conducted in JMP 15.1 (SAS Inc., Cary, NC). Results Twenty-five patients underwent the reinforced Ross operation. Twenty-three patients (92%) had bicuspid aortic valve and the most common indication for surgery was a combination of aortic insufficiency and stenosis (n = 18, 72%). The mean follow-up was 6.1 ± 5.0 years. All patients were alive at the time of follow-up. Six patients (24%), from early in our experience, required subsequent aortic reintervention. Median time to reintervention was 41.8 months (0-81.5 months). Sixteen (64%) patients had less than moderate aortic insufficiency at last follow-up. Additionally, average aortic root measurements remained unchanged. Conclusions The reinforced Ross technique was initially proposed as a way to mitigate aortic root dilation seen in the traditional Ross procedure. Our experience suggests an associated learning curve with the majority of aortic reinterventions occurring within the first few years following surgery. Continued follow-up is warranted to assess its long-term durability and functionality.

493 Prognostic value of myocardial scar and chamber enlargement at electroanatomical mapping during catheter ablation in adult congenital heart disease

Aims Atrial and ventricular tachyarrhythmias are common among patients with adult congenital heart disease (ACHD) and can impair quality of life and prognosis. Catheter ablation is often the main treatment option in this population, despite anatomical hurdles. Substrate mapping findings have not been thoroughly investigated as predictors of arrhythmia recurrence success and cardiovascular clinical outcome after ablation. We sought to determine the prognostic value of myocardial scar and chamber enlargement detected at electroanatomical mapping in ACHD patients undergoing catheter ablation of tachyarrhythmias. Methods and results Consecutive ACHD patients undergoing catheter ablation of atrial and ventricular tachycardias using different electroanatomical mapping systems were retrospectively identified from a hospital-based database. Scar extent detected at the electroanatomical mapping, as well as the total mapped area, was calculated. Arrhythmia recurrence, hospitalization for cardiovascular (CV) reasons, and a combined endpoint (arrhythmia recurrence and/or CV hospitalization) were evaluated during the follow-up. The relationship between the aforementioned electroanatomical findings and the patients’ outcome was assessed. Twenty patients (12 male, 60%; mean age 40 ± 11 years) undergoing atrial (n = 14; 70%) or ventricular (n = 6; 30%) tachyarrhythmia were included. Acute procedural success (arrhythmia termination and/or no reinduction) was achieved in all the patients. At a mean follow-up of 171 ± 135 weeks, eight patients (40%) had arrhythmia recurrence (4/6 in the ventricular tachycardia group, 67%, 4/14 in the atrial tachycardia group, 28%). Patients with arrhythmia recurrence had a more extensive bipolar scar (P = 0.029) and a larger total mapped area (P = 0.03) than patients without recurrence, and so did the patients with the composite endpoint (P = 0.029 and P = 0.03, respectively). Patients with subsequent CV hospitalization had a larger total mapped area than patients without CV hospitalization (P = 0.017). The presence of a bipolar scar ≥22.95 cm2 predicted arrhythmia relapse (0.039) at the multivariate analysis. Conclusions Patients with ACHD show a high recurrence rate after catheter ablation, especially for ventricular tachycardias. A large bipolar scar at the electroanatomical mapping and total mapped area predict arrhythmia recurrence, likely due to the presence of more extensive reentry circuits. A large total mapped area, which may reflect a greater disease severity, predicts both arrhythmia recurrence and CV hospitalizations. Early referral of ACHD patients for catheter ablation may be a sound strategy in order to perform the procedure in the setting of less advanced heart disease.

488 Candidacy for heart transplantation in adult congenital heart disease patients: a single-centre, retrospective, cohort study

Aims End-stage heart failure (HF) is the leading cause of death in adult congenital heart disease (ACHD) population. Heart transplantation (HTx) improves prognosis in ACHD end-stage HF but candidacy evaluation, referral pattern, and correct listing timing are not fully elucidated in this population. To evaluate factors associated to refusal from Htx in ACHD patients with end-stage HF referred for HTx evaluation. Methods and results This retrospective cohort study enrolled consecutive ACHD patients considered for HTx in our institution between 2014 and 2020 and patients undergone HTx between 2000 and 2013. Refusal from HTx served as primary study endpoint. Between 2014 and 2020, 46 ACHD patients were evaluated for HTx, 14 ACHD patients underwent HTx between 2001 and 2013. The main indication to HTx in patients with single ventricle physiology was Fontan failure, while in patients with systemic left ventricle and systemic right ventricle physiology, it was systemic ventricular dysfunction. We compared clinical, anatomical and demographic data of 41 patients accepted for transplantation with 15 patients refused after screening. Risk factors for refusal were: coexistence of multiple high risk features [odds ratio (OR): 3.6; 95% confidence interval (CI): 1.1–12.9; P 0.048]; anatomical factors (OR: 14.5; 95% CI: 3.1–68.4; P 0.001), out-of-centre ACHD/HTx program referral (OR: 5.3; 95% CI: 1.5 to 19.0; p 0.01). Survival in patients accepted for HTx was significantly higher than survival in patients declined from HTx with landmark comparison at 20, 40 and 60 months of 87%, 78%, and 72% vs. 70%, 59%, and 20%, respectively. HTx refusal identifies a high risk ACHD patient subgroup (hazard ratio for overall mortality: 3.1; 95% CI: 1.1–8.3; P 0.02). Conclusions In our study risk factors for refusal from HTx are adverse anatomical features, coexistence of multiple conventional HTx high risk factors and out-of-centre referral. ACHD patients refused from HTx present shorter time to death. Efforts to increase HTx candidacy and to reduce referral delay in tertiary centre are strongly necessary for this growing population.