Left atrial longitudinal strain behavior in patients with cryptogenic stroke - a case control study

Abstract Background A significant percentage of ischemic strokes classified as cryptogenic stroke (CS) where the definition is varied according to the type of classification used. Left atrial (LA) function has a role in determining the possible cardio-embolic source of stroke. Using speckle tracking transthoracic echocardiography (TTE) we can detect the early changes in left atrial function by measuring left atrial longitudinal strain (LALS). Aim To evaluate the left atrial stain in patients with a cryptogenic stroke as compared to a healthy papulation. Method and results We recruited 50 cryptogenic ischemic stroke patients with mean age of 44.7 years and 50 % were male who treated consecutively as for first CS, and 50 age-and sex-matched healthy stroke-free controls. Using Speckle tracking TTE analysis we measured the global , passive and active longitudinal LA strain corresponding to the reservoir (LASRES), conduit(LASCD), and contractile function(LASCT),respectively in addition to standard other LA parameters and filling pressure parameters of Left ventricle(LV) in both group. Data were compared using t-test and Mann-Whitney test. Cryptogenic stroke patients as compared with controls had significantly reduced value of all components of LALS [Mean value of LASRES, LASCD and LASCT in CS group versus control group were 25.15±6.79 versus 43.95±4.62 (P-value <0.01), 14.41±3.53 versus 25.68±3.30 (P- value <0.01), 10.73±3.35 versus 18.28±1.60 (P-value <0.01) respectively] (Figure 1 and Figure 2). There were no significant differences in means of LA area and LA volume index in both groups (P value >0.05). Between parameters of LV filling pressures, it was noticed that early diastolic transmitral flow velocity (E) and early diastolic velocity at annulus (E’) were statistically lower in CS patients as compared to control group (P-value <0.01). In addition, the Cluster and Discriminant analysis used confirmed that LASRES, LASCD and LASCT were significantly lower in value in cryptogenic stroke patients in comparison to Control group which can be used to detect early LA dysfunction. Conclusion LA longitudinal strain in all components were significantly impaired in patients with CS. Measuring LALS parameters can be useful in determining early LA dysfunction in cryptogenic stroke patients.Figure 1-left atrial strain components.Figure 2 -left atrial strain component.