Impact of left atrial size and strain on new atrial arrhythmias during a 5-year follow-up in adults with congenital heart disease

Abstract

Abstract Introduction Atrial arrhythmias are a common and important cause of morbidity and mortality in adults with congenital heart disease (ACHD). In acquired heart disease, left atrial (LA) strain has been shown to predict supraventricular tachyarrhythmias (SVT). This study sought to investigate if LA strain is also a reliable predictor of SVT in the ACHD population. Method We retrospectively obtained baseline clinical and echocardiographic data, including LA function parameters and strain, in 206 ACHD patients. Only patients with sinus rhythm at baseline and 5-years follow-up were included (median age 29, IQR 22–41 years). 157 participants had a left heart defect (aortic stenosis or aortic coarctation, with or without correction) and 49 a right heart defect (Fallot physiology). Diagnosis of sustained SVT was determined from clinical reports during the follow-up period (standard 12-lead ECG, ECG Holter). Results During a median follow-up of 6.2 years, a new or recurrent sustained SVT occurred in 16 patients (7.8%). Patients baseline characteristics are depicted in Table 1. Patients who developed SVT were older, had larger LA dimensions and left ventricular mass, more likely diastolic dysfunction on echo, and a lower peak LA longitudinal strain (PALS). PALS was a good predictor of SVT risk in patients with left and right heart defects with an area under the receiver-operating-curve of 0.857. By Cox regression analysis, patient in the lowest quartile for PALS had a 16.7-fold higher hazard ratio of SVT (95% confidence interval, 4.7 to 59.0, p<0.001) in comparison with the top three quartiles. Overall freedom from arrhythmia after 1, 3 and 5 years of follow-up was 98.1%, 96.1% and 94.2%, respectively. The freedom from SVT as a function of PALS quartiles is shown in Figure 1. Conclusion PALS provides predictive information about the occurrence of SVT in the ACHD population, regardless of the type of the lesion. Including the measurement of LA strain in the follow-up of these patients may permit to better identify patients at risk of future atrial arrhythmias. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Universitätsklinik für Kardiologie, Inselspital Bern