Prognostic value of left atrial strain in ACHD patients with right-sided cardiac pathology.

BACKGROUND: Patients with adult congenital heart disease (ACHD) frequently develop late complications despite early surgical repair, including ventricular dysfunction and arrhythmias. In conditions with predominant right-sided pathology such as atrial septal defect (ASD), pulmonary stenosis (PS) and Tetralogy of Fallot (ToF), leading to right ventricular dilatation or systolic/diastolic dysfunction, ventricular interdependence may result in impaired left ventricular filling and left atrial (LA) dysfunction, despite the absence of primary left-sided disease. LA strain (LAS) has demonstrated prognostic value in acquired heart disease but its role in ACHD remains incompletely defined. OBJECTIVE: To evaluate the prognostic significance of LAS in adults with repaired right-sided CHD. METHODS: This single-centre longitudinal study includes patients with ACHD such as ASD, PS and ToF from the Quality of Life study at the Erasmus Medical Center. All patients underwent surgical repair during childhood between 1968 and 1980. Detailed cardiological evaluation, including STE-derived assessment of LA reservoir (LASr), conduit and contractile (LASct) function, was performed in 2012. Clinical outcomes were collected over a 10-year follow-up period, including mortality, reinterventions, heart failure and symptomatic tachyarrhythmias (supraventricular or ventricular) requiring treatment. RESULTS: A total of 195 patients were included (ASD=78 (40%); PS=45 (23%); ToF=72 (37%)), with a mean age of 40.7±5.2 years at the time of evaluation. Patients with ToF exhibited more frequent interventricular conduction abnormalities at baseline and had 2.7-fold higher odds of reaching the composite endpoint compared with patients with ASD. In Cox regression analyses, LASr and LASct were independently associated with symptomatic tachyarrhythmias (LASr: HR=0.952, p=0.013; LASct: HR=0.936, p=0.046), and these associations remained significant after adjustment for left ventricular ejection fraction, LA volume index or N-terminal pro B-type natriuretic peptide. CONCLUSION: LAS provides independent prognostic information after surgical repair of right-sided CHD, particularly for predicting symptomatic tachyarrhythmias. Impaired LA deformation identifies patients at increased risk, underscoring the clinical relevance of LA mechanics in ACHD follow-up.