relationship of left ventricular global longitudinal strain with cardiac autonomic denervation as assessed by 123 i- m ibg scintigraphy in patients with heart failure with reduced ejection fraction submitted to cardiac resynchronization therapy

Heart failure (hf) is associated with cardiac autonomic denervation (ad), which can be non-invasively assessed by 123i-metaiodobenzylguanidine (123i-mibg) scintigraphy and has prognostic implications. we aimed to study the relationship between myocardial contractility assessed by global longitudinal strain (gls) and ad assessed by 123i-mibg scintigraphy in advanced hf. better-hf is a prospective randomized clinical trial including hf patients (pts) submitted to cardiac resynchronization therapy (crt) who are submitted to a clinical, echocardiographic, and scintigraphic assessment before and 6 months after crt. 81 pts were included. an echocardiographic response (absolute increase in left ventricular ejection fraction ≥ 10%) was observed in 73.7% of pts. a higher baseline late heart-to-mediastinum ratio (hmr) was associated with a better echocardiographic response. there was a significant association between late hmr and gls at baseline and 6 months. at baseline, gls had an auc of 0.715 for discrimination for a late hmr < 1.6. a gls cut-off of − 9% maximized the likelihood of correctly classifying a pt as having severe ad (hmr < 1.6). myocardial contractility as assessed by gls is moderately correlated with ad as assessed by 123i-mibg scintigraphy and has a good discrimination for the identification of severe cardiac denervation. gls allow for a more readily accessible estimation of the degree of ad in advanced hf pts.