Global Left Atrial Longitudinal Strain Using 3-Beat Method Improves Risk Prediction of Stroke Over Conventional Echocardiography in Atrial Fibrillation

Abstract

Background: Atrial fibrillation (AF) is associated with a risk of ischemic stroke, and functional myocardial imaging has offered novel insights on its pathophysiology and prognosis, but its use in AF-related stroke remains limited. We aimed to evaluate the feasibility of left atrial (LA) deformations and its prognostic values of ischemic stroke in a large-scale AF population. Methods: Peak atrial longitudinal strain (LA strain), left ventricular strain (global longitudinal strain), LA strain rate (LA SR) at reservoir (LA longitudinal systolic strain rate), and early diastolic conduit (LA longitudinal early diastolic strain rate) phases were analyzed using 2-dimensional speckle tracking echocardiography. Consecutive 3-beat averaged values of strain and SR were used. The clinical end point was ischemic stroke. Results: Among 1457 AF participants, the mean LA strain, LA longitudinal systolic strain rate, and LA longitudinal early diastolic strain rate values were 12.9±4.8%, 0.80±0.28 s − 1 , and −1.17±0.46 s − 1 , respectively. There were strong positive linear relationships of 3-beat average with index-beat analysis (R=0.94, 0.94, and 0.94 for LA strain, LA longitudinal systolic strain rate, and LA longitudinal early diastolic strain rate, respectively; all P <0.001). Multivariate Cox regression models incorporating conventional echocardiography parameters demonstrated LA strain and SRs to be independent prognosticators of ischemic stroke during a median follow-up of 37.6 months. Utilization of LA strain further provided incremental value over CHA 2 DS 2 -VASc scoring ( C statistics, 0.78–0.81; P =0.006) for ischemic stroke. Overall, the prognostic performances of LA deformations were attenuated after adding global longitudinal strains in models. Conclusions: LA deformations by the 3-beat method are feasible and reproducible during AF. LA strain provided additional prognostic implication over clinical information and conventional echocardiographic measures for ischemic stroke in the AF population but not incremental to global longitudinal strains.

Left Atrial Hypertension, Electrical Conduction Slowing, and Mechanical Dysfunction – The Pathophysiological Triad in Atrial Fibrillation-Associated Atrial Cardiomyopathy

“…In addition, ACM might be important in patients with stroke (King et al, 2017;Muller et al, 2018). This might also explain that a very recent study by Liao et al (2020) demonstrated that reduced LASr (measured during AF) enabled identification of patients at risk for future ischemic stroke (Liao et al, 2020). This underlines the importance of valid non-invasive screening methods in order to identify patients at risk as early as possible and to prevent ACM-associated complications.…”

Stroke and Bleeding Risk Assessment in Atrial Fibrillation: Where Are We Now?

“…Several studies regarding the potential role of LA strain in stroke risk stratifications have been published and summarized in Figure 4 . 50) 51) 58) A lower LA strain is commonly observed in AF patients irrespective of different age strata compared to normal subjects, 58) and independently associated with an increasec risk of ischemic stroke (7.8% lower risk of stroke per 1% increase in LA strain). 50) The degree of decrease of each AF individual's LA strain from reference values can be applied in a stratified manner as standard score for organized risk stratification.…”

“… 50) 51) 58) A lower LA strain is commonly observed in AF patients irrespective of different age strata compared to normal subjects, 58) and independently associated with an increasec risk of ischemic stroke (7.8% lower risk of stroke per 1% increase in LA strain). 50) The degree of decrease of each AF individual's LA strain from reference values can be applied in a stratified manner as standard score for organized risk stratification. 51) In the previous study performed by Liao et al, 51) AF patients with a mean LA strain lower than reference values (mean values of LA strain of healthy subjects) for more than 3 standard deviations were associated with a more than 2-fold higher risk of ischemic stroke compared to those whose LA strain was lower for only 2–3 standard deviations.…”

“…Other than the components of the CHA 2 DS 2 -VASc scheme, some biomarkers and several parameters derived from imaging tools which were reported to be associated with stroke events in AF patients are summarized in Table 2 . 34) 35) 36) 37) 38) 39) 40) 41) 42) 43) 44) 45) 46) 47) 48) 49) 50) 51) 52) A biomarker-based stroke risk score, the ABC (age, biomarkers [high-sensitivity troponin and N-terminal pro B-type natriuretic peptide; NT-proBNP], and clinical history of prior stroke/transient ischemic attack) score, has been developed to predict stroke or SE in 14,701 anticoagulated AF patients enrolled in ARISTOTLE trial, and was externally validated in 1,400 participants with AF or atrial flutter (689 on OACs) in the STABILITY trial. 40) The ABC-stroke score yielded higher c-indices than the CHA 2 DS 2 -VASc score in both the derivation cohort (0.68 vs. 0.62, p<0.001) and the external validation cohort (0.66 vs. 0.58, p<0.001).…”

“…Besides, the consecutive 3-beat averaged value of LA strain is a feasible and reproducible method to overcome the irregular cardiac cycle of AF and correlated well with the index-beat method and 10-second average method. 50) Further integration of LA strain with current risk stratification schemes might be a potential manner for prognostication in the era of individualized precision medicine.…”