The Left Atrial Septal Pouch as a Possible Risk Factor for Stroke.

BACKGROUND: The left atrial septal pouch (LASP) is formed by the caudal fusion of the area of overlap of the septum primum and the septum secundum, leaving an opening toward the left atrium. The association between LASP and stroke has not been validated by the previous studies. METHODS: The prevalence of the LASP was determined in 223 ischemic stroke patients and 223 control subjects with other cardiac pathologies, in a monocentric retrospective case-control study design. Stroke subtypes were defined according to the modified TOAST criteria. RESULTS: The mean age was 66 ± 15, 54% males, with a high prevalence of cardiovascular risk factors. The prevalence of the LASP was 81 (18%), irrespective of age or pathology. The number of LASP was similar in the stroke and control groups (18% vs. 19%, P = 0.7), as well as in the cryptogenic stroke subgroup (16%, P = 0.6). LASP was not associated with ischemic stroke on univariate (OR = 1.095; 95% CI = 0.676-1.772; P = 0.7) and multivariate logistic regression analysis (OR = 1.004; 95%CI = 0.574-1.758, P = 0.98). There was no statistical association between LASP and cryptogenic stroke on univariate (OR = 1.26; 95%CI = 0.526-3.016; P = 0.6) or multivariate analysis (OR = 0.705; 95%CI = 0.193-2.577, P = 0.6). The association of LASP to AF, left ventricular dysfunction, and thrombophilia did not lead to a higher incidence of stroke (OR = 0.99; 95%CI = 0.37-2.66; P = 0.99). CONCLUSION: Our study did not show any association between LASP and ischemic stroke. A septal pouch was present in 18% of the population. Other associated risk factors need to be considered to incriminate the septal pouch as the etiology of a stroke.

The mitral annular displacement by two-dimensional speckle tracking: a new tool in evaluating the left atrial function.

BACKGROUND: The methods used to characterize the volume change and the deformation of the left atrium are highly dependent on technical factors and difficult to use in a clinical environment. The aim of this study was to demonstrate that mitral annular displacement by speckle tracking can be an alternative method to studying the longitudinal left atrial function. METHODS: Ninety study participants (54% men), with a mean age of 53(±15) years, underwent a complete echocardiographic examination, comprising two-dimensional, three-dimensional and tissue Doppler imaging (TDI). They were divided into normal individuals (35) and patients having an abnormal echocardiography (55). RESULTS: There was a very strong correlation between three-dimensional volumetric function and mitral annular displacement, both for the reservoir (r = 0.78; P < 0.0001) and contractile (r = 0.76; P < 0.0001) functions. The correlation with the longitudinal strain displayed an r = 0.87, P > 0.0001 for the reservoir and r = 0.81, P < 0.0001 for the contractile function. The systolic speed in pulsed TDI and the systolic displacement had an r = 0.83, P < 0.0001. Mitral annular displacement was a very good discriminator for normal versus abnormal participants [area under the curve (AUC) for reservoir = 0.872 and for contractile = 0.843; P < 0.0001], performing less well than three-dimensional (AUC reservoir = 0.892 and contractile = 0.915; P < 0.0001) or deformation (AUC = 0.921 and 0.903 respectively; P < 0.0001), but better than pulsed TDI (AUC = 0.807; P < 0.0001). The percentage error was ±15% for interobserver and ±12% for intraobserver variability. The time taken for displacement analysis was 9 ±â€Š3 s for an experienced cardiologist and 12 ±â€Š4 s for a beginner. CONCLUSION: Mitral annular displacement by speckle tracking is a reliable and fast method to evaluate left atrial function. Given the strength of the correlations with strain parameters, it could be used as a surrogate measure of the deformation of left atrium.