Left atrial stiffness in young patients with cryptogenic stroke: insights from the SECRETO-study

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Finnish Medical Foundation. DC recieves funding from Helse Vest Background Cryptogenic ischemic stroke (CIS) in young adults is an increasing health issue with potentially different etiologies than stroke at older age. Low left atrial (LA) reservoir strain (LASr) is a predictor of both recurrent stroke and subclinical cerebral infarct in older populations. LASr and LA stiffness have not yet been explored in young CIS patients. Purpose To assess LA stiffness and associated factors in patients experiencing CIS before the age of 50 years. Methods In the prospective, multi-center SECRETO (Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Triggers, Causes, and Outcome) study, patients aged 18–49 years with first-ever imaging-proven CIS underwent echocardiography within 2 weeks after admission. LA volumes were measured at end-diastole (minimum) and end-systole (maximum) and LA strain assessed as LASr and contractile strain. LA stiffness was derived from the ratio: mitral peak E-wave velocity divided by the mitral annular e’ velocity (E/e´) / LASr and classified as increased for age if ≥ 0.22. Systemic arterial compliance (SAC) was calculated as the left ventricular Doppler stroke volume divided by pulse pressure. Results Among 146 CIS patients (mean age 39 ± 8 years, 45% women, 34% normal weight), LA stiffness was increased in 34% of patients and more often in overweight and obese patients with low SAC (p<0.001, Figure 1A). Patients with high LA stiffness for age had larger minimum LA volumes and LV mass, and lower LA ejection fraction (EF) and LA contractile strain (p<0.001, Figure 1B). In multivariate regression analysis, increased LA stiffness was independently associated with higher age and body mass index, and lower LA EF and SAC after adjustment for sex and LV EF. In subsequent models, replacing LA EF with LA volume, increased LA stiffness was associated with larger minimum LA volume (p<0.001), but not maximum LA volume. Conclusion LA stiffness is increased in one-third of young patients with CIS, reflecting in part the cardiac remodeling induced by increased body mass index, reduced SAC, and ageing. This provides mechanistic insights into the link between these risk factors and the occurrence of CIS in young patients.