Left Atrial Function in Recurrent Stroke of Unknown Cause
Left Atrial Function in Recurrent Stroke of Unknown Cause
Stroke is an important cause of disability and the third leading cause of death.

 Approximately 30 to 40 % of all strokes are estimated to be cryptogenic (i.e. no cause can be
 found). There have been few previous studies regarding risk stratification for stroke
 recurrence in patients with cryptogenic stroke.

 Recent studies have suggested that left atrial (LA) function is an important determinant of
 stroke risk. However, most studies focus on volume indices and LA dimensions, we also want to
 investigate other echocardiographic parameters. The aim of this study is to assess the
 predictive value of left atrial function for the risk of stroke recurrence and/or atrial
 fibrillation by transthoracic echocardiography in cryptogenic stroke patients with no proven
 atrial fibrillation (AF) and no indication for anticoagulants.
Study design and population The investigators used a retrospective mono-centric case-control
 design and analyzed all patients admitted for cerebrovascular accident (CVA) or transient
 ischemic attack (TIA) between 2011 and 2014. The investigators searched for patients who had
 a recurrent CVA/TIA and/or who were diagnosed with newly documented AF during the study
 duration. Clinical, demographic and laboratory parameters were assessed. Echocardiographic
 parameters, measured on first admission, were analyzed using EchoPAC version 112.

 Statistical analysis Univariate analysis was performed for all covariates using the Cox
 proportional hazards model. Likelihood ratio tests were used to determine significance for
 all parameters.

 If covariates were significant at the 25% significance level, they were used in the
 multivariate model.

 Multivariate analysis was performed using the Cox proportional hazards model with backward
 elimination model selection. The Wald Chi-Square test was used to determine significance at
 5% significance level. The program used for analysis is SAS version 9.4.
Inclusion Criteria:

 -  CVA

 -  TIA

 Exclusion Criteria:

 -  proven AF or atrial flutter

 -  prior ablation for AF

 -  valvular disease

 -  artificial heart valves

 -  endocarditis

 -  presence of an atrial septum defect or moderate to large patent foramen ovale

 -  LV akinesia

 -  moderate to severe carotid stenosis

 -  prior surgery for carotid artery stenosis

 -  total occlusion of the internal carotid artery

 -  carotid artery dissection

 -  vertebral artery dissection

 -  massive aortic atheromatosis

 -  temporal arteritis

 -  basilar artery aneurysm

 -  ascending aortic aneurysm

 -  subclavian steal

 -  prior CVA/TIA

 -  intracerebral hemorrhage

 -  lacunar infarction

 -  clotting disorder

 -  on anticoagulants

 -  CVA/TIA as a procedural complication

 -  hyperthyroidism

 -  patients who died in hospital after first admission for CVA/TIA